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Diet and Nutrition

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Vitamin E supplements

If you’ve been taking vitamin E supplements, you’re not alone. The positive results of early studies on the antioxidant led many to take it in hopes of preventing or slowing everything from respiratory infections to macular degeneration. But what proves hopeful in early, preliminary studies doesn’t always pan out in larger research settings, and vitamin E is a case in point.

Age- Related Macular Degeneration

Age- Related Macular Degeneration (AMD) is the breakdown of cells of the macula, the small part of the eye that allows us to see things sharply and in color. Little is known about what causes AMD, which is the leading source of vision loss in people older than 55.

Early observational studies showed vitamin E might help prevent macular degeneration. To test this theory, researchers recruited close to 1,200 participants between the ages of 55 and 80 to receive either a daily vitamin E supplement or a placebo for four years. Participants underwent annual eye exams to detect signs of development or progression of AMD and changes in visual function.

The results of this study showed the incidence of AMD was similar among participants in the two groups. In the vitamin E group 8.6% developed AMD, whereas 8.1% in the placebo group did. Though this study clearly indicates that vitamin E does not help prevent or slow the progression of AMD, the study period was short, so it doesn’t prove that vitamin E doesn’t help in the long run.

(British Journal of Medicine, July 6, 2002)

Respiratory Infections

Early studies showed that vitamins and minerals, particularly vitamin E, may boost immune response in healthy elderly people. With this in mind, Dutch researchers set out to investigate whether either of the supplements lessens the rate and severity of respiratory infections in the elderly.

The researchers enlisted 652 participants over the age of 60 and broke them randomly into four groups. Each day, they either took a multivitamin with minerals and a placebo, a vitamin E pill and a placebo, both a multivitamin with minerals and vitamin E pill, or two placebos. After fifteen months of follow-up, the researchers found that the rate of respiratory infections did not differ among the groups. However, those who took vitamin E supplements actually had respiratory infections that were more severe — they were longer, caused more symptoms, and restricted more of the sufferer’s activities.

(Journal of the American Medical Association, August 14, 2002)

February 2003 Update

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Food labels to list trans fat

Sometime next year the Food and Drug Administration will require food makers to list how much artery-damaging trans fat their products contain.

Trans fats, also called trans fatty acids, are found in hydrogenated or partially hydrogenated vegetable oils. Trans fatty acids are the byproduct of partial hydrogenation, a process that solidifies unsaturated oils. Hydrogenation increases the shelf life of products made with these oils, yet it also turns the relatively “safe” unsaturated fats into trans fatty acids, which are no better (and possibly worse) than saturated fat. Saturated fat had long been heralded as the “bad” kind of fat until research in the 1990s showed that trans fat is actually worse.
In a report to the FDA earlier this year, the Institute of Medicine said Americans should cut back their intake of trans fats but there was not enough research to recommend a safe daily level.

According to federal officials, trans fat will be labeled on a separate line from saturated fat, telling people exactly how much of each they are eating. Until food labels are changed, however, the only way to know what you're eating is to read food labels carefully. If partially hydrogenated oil is listed as one the first ingredients, the product likely has a lot of trans fat. Deep fried foods, such as donuts and French fries, top the list of food with high levels of trans fats.

There are also many “hidden” sources of trans fats, including vegetable shortening and stick margarines. The rule of thumb with margarines and spreads is the softer, the better (that is the lower in trans fats). Trans fats also occur naturally in meat, but at much lower levels.

November 2002 Update

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Dietary Antioxidants May Decrease Risk of Alzheimer's Disease

Alzheimer’s disease (AD) is a complex disease that spreads through the brain. It affects some 4 million Americans, causing memory loss, impaired thinking, and changes in personality. Scientists have suspected that substances called antioxidants — vitamin C, vitamin E, and beta carotene, for example — may guard against AD. However, studies testing the relationship between antioxidant supplements and the risk of AD have not found consistent evidence of a benefit. But now two studies published in the Journal of the American Medical Association have found that high intakes of antioxidants from food may reduce the risk of developing AD.

In the first study, researchers recruited 5,395 participants with an average age of 67.7 years, who lived independently. All participants reported their eating habits and went through two mental state examinations to ensure that they were free of dementia at the start of the study.
During six years of follow-up, the researchers re-screened the participants for Alzheimer’s disease. They found that high dietary intake of vitamin C significantly reduced the risk of developing Alzheimer’s disease and that the reduced risk of AD from high dietary intake of vitamin E was also borderline significant. These antioxidants were most effective at preventing AD in current smokers, compared with current non-smokers.

Use of dietary supplements was controlled in this study, so the beneficial effects of vitamins C and E were only from food. Vitamin C is found in large amounts in citrus fruits, kiwi, and broccoli, and good sources of vitamin E include nuts, milk, and egg yolk.

In the second study, participants were also free of Alzheimer’s disease at the beginning and completed a food frequency questionnaire. The questionnaire helped researchers keep track of the intake of certain foods and supplements. The 815 subjects were 65 years and older, and were followed for four years.

After adjusting for age, education, sex, race, and presence of APOE e4 (a genetic characteristic that makes a person more likely to develop AD), the researchers found that those with the highest dietary intake of vitamin E were 70% less likely to develop AD than those with the lowest dietary intake of vitamin E. However, the highest Vitamin E intake for the study was 363.6 International Units (IU) per day, well above the Recommended Dietary Allowance of 22 IU.

The other dietary antioxidants tested in this study, vitamin C and beta carotene, did not reduce the risk of AD. More research will need to be performed to find out why vitamin C proved effective in one study but not in the other. While dietary antioxidants are proving more effective in reducing Alzheimer's risk than antioxidant supplements, these weren't randomized, clinical trials, so these studies won't translate into dietary recommendations.

August 2002 Update

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Drinking Tea Benefits Heart and Bones

The health benefits of drinking tea have been well publicized lately, and recent studies point to two newly discovered advantages to consuming this beverage. One shows that drinking tea can help prevent death after a heart attack. The other reports that tea may increase bone mineral density, which helps prevent fractures and osteoporosis.

In the first study, published in Circulation, researchers questioned 1,900 patients hospitalized for heart attacks about the amount of caffeinated tea they drank in the past year. After adjusting for age, gender, and other variables, researchers found that those who drank 14 or more cups of tea per week were 39% less likely to die of cardiovascular disease in the 3.8 years following their heart attack than non-tea drinkers. Patients who consumed 1–14 cups of tea per week were 31% less likely to die from cardiovascular causes during that period than non-tea drinkers.

When researchers further looked into subjects' caffeine intake, they found that caffeine from sources other than tea did not affect death rates.

In the second study, published in the Archives of Internal Medicine, researchers surveyed 1,037 men and women age 30 and older about their tea consumption. Subjects who drank tea at least once a week for the preceding six months were labeled "habitual tea drinkers." This group was asked about their tea-drinking history, the kind of tea they drank, how often they drank it, and how much they drank in each sitting.

Researchers then measured the bone mineral density (BMD) of the lumbar spine, hip, neck, and total body of both the habitual tea drinkers and the non-drinkers.

The researchers found that people who consumed tea regularly for more than 10 years had the highest BMD scores compared to the other groups, after they adjusted for sex, age, weight, and lifestyle variables that may affect BMD. Those who drank tea regularly for the past 6–10 years also had significantly higher lumbar spine BMDs than the nonhabitual tea drinkers. People who consistently drank tea for the past 1–5 years did not have any significant differences in BMD score compared to the nonhabitual drinkers.

It didn't seem to matter what type of tea the person drank, and neither did the amount of tea consumed each time. Only duration of habitual tea consumption was an independent predictor of BMD score. Tea contains several components, including fluoride and flavonoids, which may work separately or in concert to maintain or restore bone density.

Although BMD score is often a good gauge of the risk of fracture from osteoporosis, this study did not actually test the link between tea consumption and bone fracture.

July 2002 Update

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New guidelines for stroke prevention

With more than 700,000 Americans having strokes each year, doctors and patients need to focus on stroke prevention. In light of this, the American Heart Association (AHA) has issued a statement that details how to identify and modify risk factors. Here are the AHA's tips, along with other general guidelines for lowering stroke risk:

Blood pressure. You should get your blood pressure checked at least every two years because many people with high blood pressure don't even know they have it (130–139 mm Hg systolic pressure over 85–89 diastolic pressure is considered high-normal, while anything above 140 over 90 is considered high). If you have high blood pressure, the following lifestyle changes can help lower it:

  • Eat more fruits and vegetables. Potassium-rich foods like bananas and oranges may be especially good.
  • Pass on salt. Salt makes the body hold onto water, and the heart has to work harder to pump the extra fluid.
  • Lose weight. The heavier you are, the harder your heart has to work to pump blood to all parts of your body.
  • Exercise. Even if you don't need to lose weight, exercise can reduce high blood pressure and may even prevent it.
  • Limit your alcohol. Having more than two alcoholic drinks a day significantly increases your risk of high blood pressure.
  • Quit smoking. Smoking increases your risk of heart attack, as well as many other diseases. And if you live with a smoker, make sure he or she quenches his cravings outside. Exposure to secondhand smoke can double your risk of stroke.
  • Learn to relax. Various kinds of behavioral therapy, like biofeedback, yoga, and tai chi may lower blood pressure.

These lifestyle changes can also help with other causes of stroke, like
atherosclerosis (hardening of the arteries) and high cholesterol. If the changes don't lower your blood pressure, your doctor may prescribe a medication such as a diuretic or beta blocker.

Other conditions. The AHA recommends that patients with diabetes and children with sickle cell disease closely monitor their blood pressure with screenings every six months.

Non-modifiable risk factors. Black, Hispanic, Chinese, and Japanese people are at increased risk for stroke compared to whites. Men and postmenopausal women are also at higher risks than others. If one of your parents had a stroke, you are at greater risk as well, either because of genetics or shared lifestyle traits.

While you can't do anything about non-modifiable risk factors it's helpful to know if you fall into a high-risk group so you can carefully monitor controllable factors.

July 2002 Update

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Healthy Diet Eradicates Need for Trendy Supplements in Elderly

Magazine ads and television commercials tout dietary supplements that claim to be a veritable fountain of youth for seniors. Images of grandparents able to keep up with their grandkids convince older adults that shakes, energy bars, and special vitamins will help boost energy and decrease signs of aging.

Health experts, however, stress that a well-balanced diet rich in fruit and vegetables is just as effective and probably safer. But many older adults skip meals and eat small amounts of fruits and vegetables, citing reasons ranging from rotten teeth to unhappiness with eating alone.

While doctors acknowledge that nutritional shakes and energy bars are helpful for seniors who need to gain weight or have trouble chewing or swallowing, those who eat a balanced diet or stay active do not need them.

In spite of what the experts have said, the savvy advertisements are convincing millions of seniors that they need these expensive supplements, some of which have not even been proven safe.

Herbs are also a source of concern. Saw palmetto, an extracts made from the fruit of the saw palmetto plant, is promoted as a treatment for an enlarged prostate. Many people believe that herbs are natural and therefore safe but this is not the case. In fact, as with most nonprescription herbal products, the composition of the extract and the dosage have not been standardized and the supplement is not regulated by the FDA. If you decide to use saw palmetto, tell your doctor in order to alert him or her to possible interactions between it and other medications you may be taking.

People who are on strict diets — like those prescribed for kidney disease, heart disease, or diabetes — must be especially wary of adding any special supplements to their diet. Regardless of whether health problems are present, you should always consult a physician before starting any dietary regimen.

May 2002 Update

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Fish for Good Health

In April, three studies delivered powerful evidence that fish is good for you — and could even save your life. The key is omega-3 (or n-3) fatty acids, beneficial polyunsaturated fats provided by many kinds of fish and certain plant foods.

Researchers in the Nurses' Health Study examined 16 years of data involving almost 85,000 women and found an association between fish intake and a lower risk for heart disease and death. Women who ate fish just once a week had a heart attack risk 29% lower than those who ate it less than once a month. Women who ate fish five times a week had nearly half the risk of death from a heart attack.

The Harvard's Physicians' Health Study, which involves more than 22,000 male doctors who initially had no heart disease, analyzed blood levels of omega-3 fatty acids and risk for sudden cardiac death. Researchers found that such deaths were 81% less likely in men with the highest levels of omega-3s. Over half of such deaths occur in people without prior symptoms of heart disease — a compelling reason for adding more fish to your diet.

Finally, Italian researchers reported that heart attack survivors who took fish-oil supplements had a lower risk of sudden death. This trial studied omega-3 fatty acids and vitamin E in 11,000 men and women who had recently suffered heart attacks. Researchers found that 1 gram of omega-3 fatty acids daily reduced the risk for sudden coronary death by up to 42%. This benefit apparently reflects their calming effect on arrhythmias, potentially fatal heartbeat irregularities. Omega-3 fatty acids may also inhibit clotting and improve blood vessel function. The American Heart Association recommends four servings of fish per week but doesn't endorse supplements because of too few data on the subject.

May 2002 Update

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Asthma Education Leads to Improvement in Children

Managing your child's asthma should include meeting with an asthma educator a few times, according to a follow-up study. Presented at the meeting of the American Academy of Allergy, Asthma, and Immunology, the study reports that after attending an interactive training program three times patients felt less worried about their asthma and had fewer asthma-induced awakenings during the night. Both patients and their caregivers, who also took part in the program, made better decisions about asthma care.

The 30 subjects, asthmatic children ages 6–12, underwent ACE IT! (Asthma Care Education: Intensive Training), an interactive, small-group education program. The sessions included a motivational talk by a teenage athlete with asthma and a pharmacist's discussion of medications. A nurse and asthma specialist also taught the participants about the clinical nature of asthma, environmental controls, relaxation techniques, and asthma action plans.

Researchers evaluated the children at the beginning and end of the training, after six months, and again a year later. After the courses, the number of patients reporting two or more nocturnal awakenings per month dropped from 9 to 5, and the number of symptom-free days also improved, from an average of 20 days per month to over 25 days per month.
The patients were more willing to use the tools available to them, such as medications and peak flow meters, devises that asthmatics breath into to help detect airway changes. They also worked harder to avoid things that triggered their asthma, such as pets or dust.

The researchers plan to continue tracking these 30 children to study the long-term effects on quality of life, morbidity, and cost of treatment. A previous study published in the Journal of Allergy and Clinical Immunology in 2000, found that the training program was much more effective than simply handing out educational materials.

May 2002 Update

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New Diabetes Guidelines from the ADA

In the January 2002 supplemental issue of Diabetes Care, the American Diabetes Association (ADA) released a compilation of all its position statements on diabetes care, including three new ones. It includes the first update of the ADA's nutrition guidelines since 1994.

One of the reports, Evidence-Based Nutrition Principles for the Treatment and Prevention of Diabetes, outlines changes as to how diabetics should approach carbohydrate intake, giving them more dietary freedom. Previously, diabetics were advised to avoid eating simple sugars and fast-acting carbohydrates like table sugar because these were believed to be more rapidly absorbed than complex starches found in such foods as potatoes, thus aggravating hyperglycemia. But there is little scientific evidence to support this theory. In fact, the simple sugar sucrose is no worse for a diabetic than starch, so the ADA now recommends simply using the carbohydrate terms sugar, starch, and fiber instead.

The new guidelines also advise that it's more important for people with diabetes to monitor and adjust their insulin requirements according to the total amount of carbohydrates in food rather than the source or type. They therefore dismiss the practical value of the glycemic index, which calculates how quickly the carbohydrate content of a person's overall diet raises blood sugar levels. Nevertheless, some carbohydrate sources are healthier than others, so the ADA recommends diabetics get their carbohydrates from whole grains, fruits, and vegetables because they are also rich in fiber, vitamins, and minerals.

Diets rich in carbohydrates and low in fats used to be recommended for all patients with diabetes but this has changed since the discovery that diets rich in monounsaturated fatty acids lead to improvements in HDL ("good") cholesterol levels, triglyceride levels, and overall diabetes control.

The use of fructose as an added sweetener is not recommended, but natural fructose in fruits and other sweeteners like saccharin and aspartame appear to be safe. The guidelines address many other important nutrition issues, but specifically they recommend that diabetics get 60%–70% of their caloric intake from carbohydrates and monounstaturated fats, 15%–20% from protein, and less than 10% from saturated fats. Overall, these new options afford diabetics more choices in their diets-choices that will provide a diet more people can adhere to.

Another of the reports, Treatment of Hypertension in Adults with Diabetes, addresses hypertension, which occurs in up to 60% of diabetics and substantially increases the risk of vascular problems, such as coronary heart disease and other serious complications. The most recent evidence supports the use of aggressive hypertension treatment to avoid these complications. The ADA recommends people with diabetes aim for a blood pressure (BP) of less than 130/80 mm Hg. If a diabetic's BP is 130–139/80–89, the report suggests adopting behavioral changes such as reducing salt intake, losing weight, and becoming more physically active. However, if his or her BP is greater than 140/90, drug treatment should be started. Angiotensin-converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), diuretics, and beta blockers are recommended as first-line treatments. In many cases, patients will need three or more drugs to control their BP.

The third report, Standards of Medical Care for Patients with Diabetes Mellitus, is a comprehensive guide intended to provide an overview of the components of diabetes care, treatment goals, and tools to evaluate the quality of care. It also goes over strategies for successful guideline implementation. For instance, successful programs give patients access to nurses for case management services, diabetes educators, and group visits.

For the complete reports, go to http://care.diabetesjournals.org/content/vol25/suppl_1/.
April 2002 Update

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New Cancer Prevention Guidelines

While some risk factors for developing cancer, such as family history, can not be changed, there are ways for people to reduce their chances. The American Cancer Society (ACS) recently released new dietary and physical activity guidelines for cancer prevention.

One of the most basic tenets of a healthy diet is eating plenty of fruits and vegetables. The ACS recommends eating no less than 5 servings of a variety of fruits and vegetables every day. Many people have heard of antioxidants but aren't sure exactly what they are or what they do. Antioxidant nutrients (such as vitamin C, vitamin E, and carotenoids) protect the body against the tissue damage that occurs as a result of normal metabolism. Because such damage is associated with increased cancer risk, the antioxidant nutrients are thought to protect against cancer. Studies suggest that people who eat more vegetables and fruits, which are rich sources of these antioxidants, have a lower risk for some types of cancer, but studies of antioxidant supplements have not yet shown a reduction in cancer risk.

Choosing whole grains over processed (refined) grains and sugars will also help, so stick to whole grain rice, bread, pasta, and cereals. Also, limit your red meat intake. When you do eat it, choose the way you cook it carefully. While adequate cooking is necessary to kill harmful microorganisms in meat, some research suggests that frying, broiling, or grilling it at very high temperatures creates chemicals that might increase cancer risk. Braising, steaming, and poaching meats cuts down on the production of these chemicals.

Drinking too much alcohol is an established cause of cancers of the mouth, throat, liver, and breast. Therefore, the ACS recommends limiting alcoholic consumption to 2 drinks per day for men and 1 drink per day for women.

The ACS also reminds people to remember that "low fat" or "fat free" snacks like cakes and cookies are often high in calories. High sugar intake can lead to obesity and elevated insulin levels, conditions that increase cancer risk.

Physical activity is also an important component in the prevention of cancer. Adults should engage in moderate-to-vigorous activity (walking, leisurely bicycling, running, swimming) for 30 minutes or more at least 5 days a week.

Simple additions to your daily routine such as taking the stairs instead of the elevator, taking 10-minute exercise breaks at work, and walking to visit co-workers instead of emailing them are simple ways to increase your activity level.

An unhealthy diet and lack of exercise can lead to weight gain and obesity, conditions that are associated with developing cancers of the breast, colon, endometrium, esophagus, gallbladder, pancreas, and kidney.

In addition to the general guidelines set forth by the ACS, there are also answers to frequently asked questions about the rumored or theoretical relationships between cancer and such substances as aspartame, beta-carotene, calcium, coffee, fish oils, fluorides, folic acid, saccharin, and tea.

The ACS suggests that public, private, and community organizations create environments that support the adoption and maintenance of these healthful eating and physical activity behaviors. People should have access to healthful foods in schools, at work sites, and when on daily outings in their town or city.

For a copy of the complete set of guidelines, call the American Cancer Society at 1-800-ACS-2345.
April 2002 Update

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Obesity in Children is on the Rise

A recent study published in the Journal of the American Medical Association showed that American children are heavier now than ever before. In 1998, 12%, 21%, and 22% of Caucasion, African American, and Hispanic children, respectively, were classified as overweight. In fact, between 1986 and 1998, the prevalence of overweight children rose steadily among these groups.

The reason behind childhood obesity — that kids are taking in more calories than they're expending — is easy to understand. But diagnosing obesity is more complicated. It cannot be diagnosed simply by looking at someone because ideal body images differ among individuals, and different body shapes carry weight differently.

And changing lifestyles that create obesity may be even harder. Children are spending more time than ever watching television, playing video games, and surfing the Internet instead of being active. Their parents are busier than ever, too, making it harder to cook nutritious meals.

This is all problematic, as obesity is a risk factor for many health problems, both in childhood and later in life. Children who are overweight are more likely to develop high blood pressure, high cholesterol, and heart disease as adults than kids of normal weight. Long-term obesity also increases the risk of arthritis, heart disease, diabetes, and certain kinds of cancer.

So what can you do? First, talk with your child's doctor. Objective standards have been developed for defining and measuring obesity. He or she will use the body mass index (BMI), calculated from your child's weight and height, and compare it with national growth charts.

There are also tangible things parents can do to help prevent (and treat) obesity in their children as well as in themselves. Begin by establishing healthier eating habits and promoting a more active lifestyle. For example, you can plan daily family activities that involve exercise; limit television, computer, and video game use; eat meals together as a family whenever possible; and when eating out, choose lower fat items on the menu.
March 2002 Update

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Advanced Macular Degeneration and Nutritional Supplements

Nutritional supplements may help slow the progression of advanced macular degeneration (AMD), the most common cause of vision loss in people over age 55, a new study suggests.

The Age-Related Eye Disease Study (AREDS), reported in the October 2001 Archives of Ophthalmology, is the largest clinical trial to have tested the impact of nutritional supplements on AMD and cataracts. AREDS involved nearly 5,000 women and men, ages 55-80, at 11 clinical centers nationwide. Participants in the macular degeneration portion of the study were divided into groups depending upon the severity of their condition. They received one of the following daily regimens: 1) antioxidants (500 mg vitamin C, 400 IU vitamin E, 15 mg beta-carotene), 2) zinc (80 mg, plus 2 mg copper to prevent anemia), 3) a combination of the antioxidants and zinc, or 4) a placebo. Participants were evaluated every six months for vision loss and annually for retinal changes.

Over the seven-year study, combined antioxidants and zinc reduced the risk for progression to advanced AMD by 25%, compared with placebo, among those who already had extensive intermediate or large drusen or advanced AMD in one eye. This treatment also reduced the AMD-related loss of visual acuity by about 19%. Antioxidants or zinc alone reduced the risk, but to a lesser extent. AREDS subjects with early or no AMD got no measurable benefit from the supplements. In the companion study of cataract development, antioxidants and zinc (separately or in combination) had no beneficial effect.

Though participants reported no major side effects, the long-term consequences of taking these nutrients at levels above the Recommended Dietary Allowance (RDA), as AREDS participants did, are unknown.
January 2002 Update

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Salt Restriction More Potent Than Exercise

Physicians often give patients with hypertension a daunting list of lifestyle changes to help lower their blood pressure: lose weight, exercise more, eat less salt, drink less alcohol, eat more foods rich in calcium, potassium, and magnesium. Of course, these changes do work — people who follow them can reduce their need for medications or even do without blood pressure-lowering drugs. But which of these lifestyle changes gives you the biggest bang for your buck?

University of Colorado researchers recently compared the impact of exercise or moderate salt restriction in 35 healthy older women with high-normal blood pressure or mild hypertension (systolic blood pressure 130–159 mm Hg), none of whom were using drugs to lower their blood pressure. Half the women exercised for three months — starting at 30 minutes a day three or four times a week and working up to 45 minutes a day every day, if possible. The other half tried to reduce their daily salt intake to less than 2.4 grams of sodium (the amount in a level teaspoon of table salt) without otherwise changing their diets. All were asked to try to avoid gaining or losing weight.

The clear winner, reported in the American Journal of Cardiology, was sodium restriction. Among the women who ate less salt, average systolic blood pressures fell 16 mm Hg, compared with a still-respectable 5 mm Hg in the exercise group. By the study's end of the study, systolic blood pressure was lower in 88% of the women who ate less salt and in 55% of the exercisers.

So if you're trying to lower your blood pressure, should you just forget about exercise and work harder at eating less salt? No. Exercise has other benefits besides lowering blood pressure — it can help control weight, improve the cholesterol profile, stave off diabetes, and keep bones strong. The real message from this study is that everyone should exercise, but that people who are trying to control blood pressure should lower their sodium intake, too.
December 2001 Update

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Diet and Exercise Dramatically Delay Type 2 Diabetes

Americans at high risk for type 2 diabetes can sharply lower their chances of getting the disease with diet and exercise, according to the results of a major clinical trial. The same study also found the oral diabetes drug metformin (Glucophage) reduces diabetes risk, though less dramatically.

The findings came from the Diabetes Prevention Program (DPP), a major clinical trial comparing diet and exercise to metformin in 3,234 people with impaired glucose tolerance, a condition that often precedes diabetes. Smaller studies in China and Finland had previously shown diet and exercise can delay type 2 diabetes in at-risk people. But the DPP, conducted at 27 centers nationwide, is the first major trial to show diet and exercise can effectively delay diabetes in a diverse American population of overweight people with impaired glucose tolerance (IGT). IGT is a condition in which blood glucose levels are higher than normal but not yet diabetic.

Of the 3,234 participants enrolled in the DPP, 45 percent are from groups that suffer disproportionately from type 2 diabetes: African Americans, Hispanic Americans, Asian Americans and Pacific Islanders, and American Indians. The trial also recruited others known to be at higher risk for type 2 diabetes, including people age 60 and older, women with a history of gestational diabetes, and people with a first-degree relative with type 2 diabetes.

Participants ranged from age 25 to 85, with an average age of 51. All had impaired glucose tolerance as measured by an oral glucose tolerance test, and all were overweight, with an average body mass index (BMI) of 34. They were randomly assigned to one of the following groups: intensive lifestyle changes with the aim of reducing weight by 7 percent through a low-fat diet and exercising for 150 minutes a week; treatment with the drug metformin (850 mg twice a day), approved in 1995 to treat type 2 diabetes; and a standard group taking placebo pills in place of metformin.The latter two groups also received information on diet and exercise.

During an average follow up of about 3 years, about 29 percent of the group receiving standard treatment developed diabetes. In contrast, 14 percent of the diet and exercise, and 22 percent of the metformin arms developed diabetes. Volunteers in the diet and exercise arm achieved the study goal, on average a 7 percent — or 15-pound — weight loss, in the first year and generally sustained a 5 percent total loss for the study's duration. Participants in the lifestyle intervention arm received training in diet, exercise (most chose walking), and behavior modification skills.

In all, participants in the random intensive lifestyle intervention reduced their risk of type 2 diabetes by 58 percent, and those who received metformin reduced their risk of getting type 2 diabetes by 31 percent.
September 2001 Update

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More Encouraging Data on Alcohol and the Heart

Having a drink or two per day lowers your risk heart disease and stroke. Little surprise then that two new studies report people who drink alcohol also have lower risk of developing heart failure and better outcomes if they have heart attacks. The studies were reported in a recent issue of the Journal of the American Medical Association.

The first study involved 1913 adults who were admitted to 45 different U.S. hospitals between August 1989 and September 1994 for heart attacks. The researchers, who were based at Harvard Medical School and Harvard School of Public Health, interviewed the patients an average of 4 days after their heart attacks, inquiring about a range of issues including their alcohol consumption.

About half (47%) reported they didn't drink alcohol during the year before their heart attacks. Another 36% said they drank fewer than 7 drinks per week. The remainder (17%) said they had 7 or more drinks per week. Those who drank the most were younger, and more likely to be male, current or former cigarette smokers, and have physically active life styles.

Survival rates were lowest for those who did not drink at all before their heart attacks and best for those who drank 7 or more drinks per week. For every 100 people, 6.3 of the abstainers died each year, compared with 3.4 of those who drink 1-6 drinks per week and 2.4 of those drank 7 or more drinks.

Heart failure

The second study was based on 2,235 elderly people (average age 74 years) who participated in a long-term epidemiological survey in New Haven, CT. None of the subjects had heart failure at the time of enrollment in the study in 1982. And the researchers excluded heavy drinkers (those drinking more than four drinks per day).

Half of the subjects reported no alcohol consumption in the month before enrollment, while 40% reported consumption of 1-20 ounces (up to 1 or 1.5 drinks per day), and 10% reported drinking 21 to 70 ounces (about 1.5 to 4 drinks per day).

During the next 14 years, 281 people developed heart failure, including 28 fatalities. The rates of heart failure for every 1000 people per year were 16.1 for abstainers; 12.2 for those who drank 1-1.5 drinks per day; and 9.2 for those who drank more heavily. Statistical analyses that adjusted for other differences among these groups concluded that light drinking reduced one's risk for heart failure by 19%, and moderate or heavy drinking reduced the risk by 53%.

Because moderate drinking can easily progress to problem drinking, no experts feel comfortable in encouraging nondrinkers to take up alcohol for medical reasons. However, researchers are debating whether some people who have given up alcohol might be encouraged to resume it. Future research may also define certain subgroups who can benefit most from alcohol, perhaps by raising their HDL cholesterol.
September 2001 Update

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New Vitamin A Recommendations

You can never get too much of a good thing or is it too much of a good thing is just that? Regardless of which saying you prefer, it appears that when it comes to vitamin A, it's possible to overdo it. In fact, the National Academies' Institute of Medicine recently lowered the recommended daily allowance (RDA) for this vital nutrient and warned people not to take megadoses of vitamin A supplements.

Vitamin A is important for normal vision, immune function, growth, and other bodily processes. To ensure adequate stores in the body, men are now being told to consume 900 micrograms (mg) daily and women 700 mg daily. However, nobody should ingest more than 3 milligrams (or 3,000 mg) per day. Recent research shows excess vitamin A intake may increase the risk of liver problems and birth defects if taken during pregnancy.

Vitamin A deficiencies, which cause vision impairment, are rare in North America. Daily requirements can be met without taking supplements if you eat a balanced diet that includes darkly colored fruits and vegetables like oranges, carrots and broccoli. However, new research found these fruits and vegetables actually yield half as much vitamin A as previously thought. So those who don't eat meats, fish, eggs or vitamin-fortified cereals need to make sure they're getting enough vitamin A. However, if you take vitamin supplements, even a regular multivitamin, you could be consuming more than what's safe. The megadoses sold in health stores can be particularly dangerous. They are often measured in "international units" and 10,000 international units is the same as 3,000 mg.
August 2001 Update

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Take Low-Dose Aspirin and Skip Vitamin E to Prevent Cardiovascular Disease

For more than 100 years aspirin has helped relieve headaches and other pain, and now new evidence from the Primary Prevention Project backs the claim it also helps prevent heart attacks and other cardiovascular events. The same study also found the antioxidant vitamin E didn't help.

The theory that anti-platelet/anti-inflammatory drugs like aspirin and antioxidant nutrients like vitamin E might interfere with atherosclerosis and prevent cardiovascular disease is not new. But previous research on both possibilities has come up with mixed results. In an attempt to resolve the debates, Italian researchers randomized 4,495 people (2583 females and 1912 men) with an average age of 64.4 to receive low-dose aspirin (100mg/day) or no aspirin and vitamin E supplements (300mg/day) or no vitamin E. They limited their investigation to people over 50 with one or more of the major cardiovascular risk factors: hypertension, high blood cholesterol, diabetes, obesity, family history of early heart attacks or individuals who were elderly.

Aspirin proved to be beneficial with respect to all of the criteria measured. It reduced the risk of a cardiovascular death by 44% and the risk of cardiovascular events or disease by 23%. However, severe gastrointestinal bleeding was more frequent in the aspirin group than in the non-aspirin group (1.1% vs 0.3%). Consistent with the negative results of other large published trials, vitamin E provided no significant improvements in any of the criteria.

The study was stopped prematurely after a mean follow-up of 3.6 years because evidence from two other studies involving a total of 24,289 patients concurred that aspirin is beneficial in primary prevention.
August 2001 Update

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Garlic’s Effects on Cholesterol Are Modest

Garlic preparations, available in most health food stores, are sold with the promise of numerous health benefits. Lower cholesterol levels are among the most touted of these benefits. Unfortunately, data from only a few small research trials support the claim that garlic preparations can lower LDL cholesterol.

A "meta-analysis" of rigorous published trials involving garlic preparations offers a better gauge of garlic’s value in reducing cholesterol. A meta-analysis mathematically pools data from several studies to better estimate the effects of an intervention — for example, a drug, dietary supplement, operation, or lifestyle change — than one could do with the data from a single, smaller study. This report, published in the Annals of Internal Medicine, reviewed 45 controlled studies involving 796 subjects (In contrast, most studies of cholesterol-reducing medications involve much larger numbers of patients). Overall, the researchers found that, on average, garlic supplements decreased total cholesterol by 16 mg/dL. But the six most rigorous studies, which also controlled for the volunteers’ diets, failed to show a significant difference in cholesterol reductions between garlic and placebo groups. (Annals of Internal Medicine, Vol. 133, No. 6, pp. 420–29.)

These results are all the more disappointing because, in general, studies that show a positive effect are most likely to be published. Thus, meta-analyses may offer an overly optimistic assessment of a drug or other intervention. In other words, "negative" studies may have simply never been published (and thus could not be included in this meta-analysis) because researchers found no difference between garlic and a placebo. If so, the value of garlic would be even less than that described here.

If you’re taking a garlic supplement, the good news is that the meta-analysis found no evidence of dangerous side effects. It simply suggests the benefits are small. But for those of you only considering these preparations, the study doesn’t offer much encouragement. Perhaps its central message is that garlic is no substitute for the highly effective, safe medications that are proven to control cholesterol and lower heart disease risk. Garlic may or may not belong in your medicine cabinet, but it has proven itself to be a vital component to any well-stocked pantry.
June 2001 Update

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National Cholesterol Education Program Releases New Guidelines for Treating and Preventing High Cholesterol

On May 15, 2001, the National Cholesterol Education Program (NCEP) — coordinated by the National Heart, Lung, and Blood Institute (NHLBI) — released the first major revision of its recommendations for detecting and lowering high cholesterol in adults since 1993.

One of the fundamental features of the new guidelines is the accurate assessment of heart disease risk using a new "global risk assessment tool" that combines multiple risk factors into a measure of a person's absolute risk of developing coronary heart disease within the next 10 years. According to the guidelines, patients who have a risk of 20% or higher should receive aggressive therapy to control cholesterol levels. In addition to aggressive treatment of high LDL cholesterol, as laid out in the 1993 report, the revised guidelines also recommend a more assertive treatment approach for diabetes, low HDL levels, and high triglyceride levels.

Specific changes include:

  • Treating high cholesterol more aggressively for those with diabetes, even if they do not have heart disease.
  • A full lipid profile (which measures total cholesterol, LDL, HDL, and triglycerides) as the first test for high cholesterol (rather than simply testing total cholesterol and HDL and performing a full lipid profile only if total cholesterol is high).
  • A new level at which low HDL becomes a major risk factor for heart disease. The 1993 guidelines defined a low HDL as less than 35 mg/dL; now it is less than 40 mg/dL.
  • More aggressive treatment of high triglyceride levels.
  • Advising against the hormone replacement therapy (HRT) as an alternative to cholesterol-lowering drugs for post-menopausal women.

Another key change in the guidelines is intensified lifestyle recommendations regarding nutrition, exercise, and weight control to treat high cholesterol. The updated diet advises that less than 7% of daily calories come from saturated fat and limits dietary cholesterol to less than 200 mg per day. It also allows up to 35% of daily calories from total fat, provided most come from unsaturated or monounsaturated fat, which doesn't raise cholesterol levels. Additionally, the guidelines strongly underscore the need for weight control and physical activity, both of which improve various heart disease risk factors.

The revised recommendations also emphasize careful attention to the metabolic syndrome, a particular cluster of cardiovascular risk factors that is becoming increasingly common in the United States. Characteristics of metabolic syndrome include too much abdominal fat, high blood pressure, high blood sugar, elevated triglycerides, and low HDL.

For more information, see the "Live Healthier, Live Longer" Web site by going to the NHLBI home page at www.nhlbi.nih.gov and clicking on ATP III Cholesterol Guidelines under Highlights.

2001 Cholesterol Guidelines
Total Cholesterol Level Total Cholesterol Category
Less than 200 mg/dL Desirable
200-239 mg/dL Borderline High
240 mg/dL and above High
LDL Cholesterol Level LDL-Cholesterol Category
Less than 100 mg/dL
Optimal
100-129 mg/dL Near optimal/above optimal
130-159 mg/dL Borderline high
160-189 mg/dL High
190 mg/dL and above Very high
Trigylceride Level
Triglyceride Category
Less than 150 mg/dL Normal
150-199 mg/dL Borderline high
200-499 High
Greater than or equal to 500 Very high
HDL Cholesterol Level HDL-Cholesterol Category
Less than 40 mg/dL Low (representing increased risk)
60 mg/dL and above High (heart protective)

 

Three Categories of Risk that Modify
LDL Cholesterol Goals
Risk Category LDL Goal (mg/dL)
Coronary Heart Disease (CHD) and CHD equivalents Less than 100
Multiple (2+) risk factors Less than 130
0-1 risk factor Less than 160
Risk factors (exclusive of LDL cholesterol): cigarette smoking; blood pressure greater than or equal to 140/90 mm Hg or on antihypertensive medication; HDL cholesterol less than 40 mg/dL; a family history of coronary heart disease before age 55 in a father or brother or age 65 in a mother or sister; age above 45 for men and 55 for women

May 2001 Update

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Study Shows Fish Consumption Protects Against Stroke, But FDA Suggests Pregnant Women Should Take Caution

A large study in the Journal of the American Medical Association (JAMA) recently showed that regularly eating fish might protect against ischemic stroke, which is the most common type of stroke. Numerous studies have already shown an association between fish consumption and a reduced risk of heart disease. But there is a caveat. The Food and Drug Administration (FDA) recently warned that pregnant women and women who are of childbearing age who may become pregnant, should avoid certain types of fish that contain high levels of mercury, which may be harmful to their unborn children.

Results of the Nurses' Health Study, published in the JAMA article, involved nearly 80,000 women. It showed that women who ate fish two to four times a week had a 48% lower risk of ischemic stroke — the kind caused by blood clots — than women who ate fish less than once per month. Even women who ate fish only once a week or less had a risk reduction, but it was not statistically significant. These results held true primarily among women who did not regularly take aspirin, which prevents the formation of blood clots. Omega-3 fatty acids, the protective substances found in fish, reduce levels of fats related to cardiovascular disease and help prevent blood clotting. Dark, oily fish such as mackerel, salmon, and sardines are a good source of omega-3 fatty acids.

Although pregnant women need not give up fish — and its beneficial health effects — altogether, they should be careful about what types of fish they eat. The FDA has advised that pregnant women and those who may become pregnant stop eating shark, swordfish, king mackerel, and tilefish. These large, long-living fish contain hazardous levels of methyl mercury, a form of mercury that can accumulate in a woman's body and affect the developing central nervous system of an unborn child. This can lead to babies with slower cognitive development. As an extra precaution, the FDA advised that nursing mothers and young children also avoid these fish. Mercury gets into both fresh and salt water through industrial pollution.

Some critics feel the FDA's mercury warnings are not strong enough. A report by the National Academy of Sciences suggested the exposure limits for mercury should be four times stricter.

While this controversy remains unresolved, the FDA encouraged pregnant women to continue to eat a variety of other fish, containing very low levels of mercury, as part of a balanced diet. Among other health benefits, the fatty acids in fish enhance brain development. According to the FDA, women can safely eat up to 12 ounces of fish per week. Fish that contain low levels of mercury include shellfish, canned fish, smaller ocean fish, and farm-raised fish. Women who eat fish caught by family or friends should contact their local health department for advice on the safety of fish from local waters.
May 2001 Update

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Children and Peanut Allergies

Children usually outgrow allergies to milk and eggs, but not to peanuts. In a recent study, researchers found that the majority of children with peanut allergies will have adverse reactions to accidental peanut exposure within five years. In addition, allergic reactions are likely to worsen over the years.

Researchers followed 83 children who were diagnosed with a peanut allergy before their 4th birthday. Of these children, 61 had initial non-life-threatening reactions, while 22 had potentially life-threatening reactions. After 5.9 years, they found that 50 of the 83 children had experienced a total of 115 adverse reactions to peanuts.

Most of the reactions increased in severity after the initial reaction. Of the children with initial non-life-threatening reactions who had additional reactions, 44% had at least one potentially life-threatening subsequent reaction. And of the 22 children who had initial life-threatening reactions followed by additional reactions, 71% had at least one additional life-threatening reaction.

In 12 of the original 83 children, the initial reaction occurred after touching, (not eating) peanuts, and they experienced only skin symptoms. Eight of these 12 had subsequent reactions, and all eight had at least one occurrence of respiratory or gastrointestinal symptoms. Children with only skin symptoms had significantly lower serum peanut-specific antibodies than those with other initial symptoms, but there was no "safe" antibody level below which subsequent reactions were only skin-specific.

Most children with peanut allergies accidentally ingest peanuts and this study showed that allergic reactions are likely to get progressively worse with each exposure. Children must be educated to avoid peanuts and foods containing peanuts. In addition, children should always have access to a self-injectable epinephrine kit that both parents and children should know how to use if the need arises.
February 2001 Update

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Low-Sodium DASH Diet Lowers Blood Pressure

The effect of reducing dietary salt on controlling hypertension, or high blood pressure, has been surprisingly controversial. But in a recent study, a collaboration of scientists, including researchers from Harvard Medical School and the National Heart, Lung, and Blood Institute of the National Institutes of Health, suggest that reducing salt intake may dramatically lower blood pressure in people with or without hypertension, regardless of age, race, or gender.

The trial, known as the Low-Sodium DASH Diet study, tested the effects on blood pressure of lower levels of sodium intake combined with the Dietary Approaches to Stop Hypertension (DASH) diet, which is low in fat and rich in fruits, vegetables, whole grains, and low-fat dairy products. More than 400 subjects were assigned either a typical American diet or the DASH diet for 12 weeks. The salt content of every participant's diet was randomly changed every four weeks to one of three sodium levels: high (3,300 mg), intermediate (2,400 mg), or low (1,500 mg).

The researchers found that with either diet, the lower the salt intake, the lower the blood pressure. But at each sodium level, blood pressure was consistently lower for those on the DASH diet. Moreover, the largest reductions in blood pressure were found among those who followed the DASH diet while consuming 1,500 mg of salt per day, well below the government's recommended daily intake of 2,400 mg, or 1 1/4 teaspoons. This combination worked best for all participants, but particularly for patients with hypertension, whose systolic blood pressure was 11.5 millimeters of mercury (mm Hg) lower than hypertensive participants on the control diet with a high sodium level. The beneficial effect of a lower sodium diet was also more pronounced in women than men and in blacks than people of other races.

Controlling blood pressure reduces the risk of developing complications associated with hypertension, which include heart disease and stroke. New dietary guidelines from the American Heart Association recommend that everyone adopt an eating plan similar to the DASH diet and limit their sodium intake to less than 2,400 mg per day. Other things you can do to keep blood pressure in check include maintaining a healthy body weight, cutting down on dietary fat, and staying active.
January 2001 Update

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High-Fiber Diet Doesn't Lower Colon Cancer Risk

Observational studies have suggested a link between diet and the risk of developing colon cancer. Consuming lots of red meat and fatty foods has been associated with a higher risk of this disease, while a diet high in fiber and fruits and vegetables seemed to lower that risk. Two recent studies in the New England Journal of Medicine suggest otherwise. In these clinical trials, researchers examined the role diet might play in the development of adenomatous polyps in the colon. (These growths are the precursors of most colon cancers.)

The first study followed 2,079 men and women who had had such polyps removed within the previous six months. These volunteers were assigned to one of two groups. The first group ate a diet that was low in fat (20% of total calories), high in fiber (18 grams of fiber per 1,000 calories of food consumed), and included 3.5 servings of fruits and vegetables per 1,000 calories of food eaten. Researchers provided the second group with a pamphlet on healthy eating and told these patients to follow their normal diets. Both groups were followed for roughly four years and had a colonoscopy (examination of the colon) once a year during this period. Surprisingly, the rate of recurrence of large polyps did not differ significantly between the two groups, leading study investigators to conclude that a low-fat, high-fiber diet rich in fruits and vegetables did not help prevent recurrence of these precancerous polyps.

The second study focused on cereal fiber, specifically wheat bran. Again, study participants included only patients who had had adenomatous polyps removed within three months of the trial's start. Of the 1,303 people who completed the study, investigators assigned 719 to a high-fiber diet (13.5 grams per day) and 584 to a low-fiber diet (2 grams per day). At the end of three years, the polyp recurrence rate was 47% in the high-fiber group and 51.2% in the low-fiber group. Again, not a significant difference.

Does this discouraging news about fiber mean people should abandon whole grains and fruits and vegetables? No. First, it is important to remember that these studies looked at whether or not the polyps returned within four years, but couldn't really assess whether diet may or may not play a role in preventing those polyps from turning into cancer. Observational studies do show that people who eat diets higher in fiber and fruits and vegetables have a lower risk of colon cancer and that when their diets change, so does their level of risk. But researchers are not yet sure why. Second, these dietary elements are important for general health and have been shown to reduce the risk of heart disease and diabetes. So make sure you eat enough fruits and vegetables and whole grains.

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Disappointing Look at Vitamin E and Heart Disease

Over the years, observational and experimental studies have suggested that regular intake of vitamin E (from supplements and food sources) can help reduce heart disease risk. The scientific theory is that the antioxidant properties of this vitamin interfere with the oxidation of low-density lipoproteins, which slow the progression of atherosclerosis. The problem with experimental studies is that these data cannot tell us exactly how a given treatment or medication will act in real human beings. And the problem with observational, or prospective studies, (which follow a group of people over time to see which among them may develop a disease or condition) is that they are not really helpful in pinpointing the reasons those people develop that disease or condition.

Randomized controlled trials are considered the gold standard for evaluating a medical or preventive treatment. Here, study subjects are matched for a set of characteristics to "level the playing field." Then researchers randomly assign some patients to get the treatment or medication and another group to get a "fake" treatment or medication. Even when applying this research method to assess the value of vitamin E in preventing heart disease, results have been mixed. One study conducted in China showed that study volunteers taking a vitamin cocktail of vitamin E, beta carotene, and selenium had a lower rate of death from heart disease, although these supplements didn't seem to lower the rate of cardiovascular incidents (heart attack or stroke). Another study looked at 29,000 older, male smokers. These volunteers took 50 mg of vitamin E per day, plus beta-carotene for five to eight years, yet the death rate from coronary heart disease remained unaffected. Men in the study who had a history of heart attack were actually more at risk for death due to heart disease. The Cambridge Heart Study was far more encouraging. This research looked at roughly 2,000 patients assigned either to vitamin E or placebo. After less than two years of follow-up, the number of non-fatal heart attacks fell significantly, but deaths due to cardiovascular problems remained the same. Some problems in the study design suggest that these results could have occurred as easily due to chance as to the vitamin E. Yet another study conducted in Italy showed that 300 mg of vitamin E per day slightly increased the number of non-fatal heart attacks, but slightly lowered the death rate due to heart disease.

The most recent study was published in the New England Journal of Medicine. As part of the Heart Outcomes Prevention Evaluation (HOPE) study, investigators assigned 772 patients to take 400 IU of vitamin E each day, and 739 patients to placebo. All the study volunteers were at high risk for cardiovascular problems because they either already had evidence of heart disease or had diabetes plus one additional risk factor. After 4.5 years, there was no hint that the vitamin E helped reduce heart problems. The death rate due to cardiovascular disease was about the same in both groups, as were the rates for heart failure, unstable angina, and bypass or angioplasty. The vitamin E hypothesis is not completely dead, however. For example, some researchers believe vitamin E might be helpful in preventing new atherosclerotic plaques or that it may be effective only if used with other antioxidant vitamins. The researchers from this study will continue monitoring patients to determine whether vitamin E helps reduce risk for cancer.

So what to do? All these studies show that vitamin E is safe and very low in side effects, so it may not be time just yet to toss it from your health regimen. But right now, the chances are low that vitamin E offers major health benefits.

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Is It Butter . . . or Medicine?

Not only can you find this product in the grocery store, but in television advertisements as well — a margarine-like spread that can help reduce cholesterol levels? Not as crazy as it sounds, Benecol is a margarine-like spread made with compounds called plant stanol esters, which have been shown to help lower cholesterol levels.

Plant stanol esters are a type of phytochemical (a chemical compound derived from plants, such as pine trees, soy, corn, and wheat) which block the LDL "bad" cholesterol from entering the micelles, the cellular structures that transfer cholesterol from the small intestine into the bloodstream. Sitostanol is particularly good at blocking intestinal absorption of cholesterol, and in its soluble form, it has an even more effective cholesterol-lowering effect.

Benecol has been available in Finland for four years, and studies there show that substituting Benecol for margarine or butter reduced cholesterol levels. In 1995, the New England Journal of Medicine published a study that evaluated the cholesterol-lowering effect of this butter substitute. This research found regular use of Benecol resulted in a 14% reduction in serum cholesterol levels (for example, a person with a cholesterol level of 240 mg/dl could get that level down to 207 mg/dl).

While this is a promising product, particularly for people who enjoy a pat of margarine on their toast or baked potato, consumers need to realize that this item is merely a supplement and no more. It is not a "magic bullet" but rather can be a useful addition to a heart-healthy diet — one that is low in saturated fats, trans fats, cholesterol, and refined carbohydrates and rich in fruits, vegetables, and whole grains. For more information on high cholesterol levels and how to reduce them, see page 669 of the Family Health Guide.

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Update on Fen-Phen and Heart-Valve Problems

Two recent studies are adding to the data concerning fen-phen and heart-valve problems. These studies should offer some reassurance to patients who took this combination of weight-loss drugs.

Researchers from Harvard Medical School evaluated echocardiograms performed on 226 people who took fen-phen as part of a long-term study from September 1994 to September 1997. Shortly after the manufacturer’s voluntary withdrawal of fen-phen, the medications were stopped and the patients underwent testing to determine if any heart-valve problems had developed. The echocardiograms showed that not one patient had severe valvular disease. Mild leaking of the aortic valve was detected in 12 patients, and three patients exhibited moderate aortic-valve leaking — a total of 15 (6.6%) patients. Three subjects (1.3%) had moderate leaking of the mitral valve. To compare the rate of heart-valve problems in these patients to the rate one might expect to see in the general population, investigators turned to data collected as part of the Framingham Heart Study (the long-term epidemiological study being conducted in a Boston suburb). They found nearly the same rates of aortic- and mitral-valve leaking in the Framingham volunteers as in the diet-drug study participants.

A second study published in the November 23, 1999, issue of the American Heart Association journal, Circulation, suggests that heart-valve abnormalities in individuals who took dexfenfluramine (Redux) may dissipate. Although study findings did link the drug to mild aortic-valve disease and moderate mitral-valve problems, it also noted that valve problems might eventually go away after drug use is stopped.

Using echocardiograms to spot heart-valve abnormalities, investigators evaluated 223 patients who had taken dexfenfluramine for an average of seven months. The tests were performed an average of 8.5 months after the participants stopped taking the drug. None of the former dexfenfluramine users was found to have severe mitral valve disease or moderate (or worse) aortic-valve disease, but 7.6% had either mild aortic-valve disease or moderate mitral-valve problems. People who had stopped treatment less than eight months before the echocardiogram were twice as likely to have valve problems than those who had been off dexfenfluramine for longer, suggesting the problem regresses.

Could it be that these diet pills are safe after all? An editorial in the Journal of the American College of Cardiology accompanied publication of the Harvard study and asked whether there was adequate proof of any increase in risk from fen-phen. No one is ready to go so far as to suggest that these drugs should return to the market, but a reasonable conclusion at this point is that there is an increased risk of heart-valve problems, though the risk is probably quite small.

Regardless of the relative risks and merits of fen-phen — and of diet drugs in general — weight loss remains a problem that cannot be solved by any "magic bullet." Medications may help a little in some patients, and surgical solutions might be considered for severely overweight individuals. However, for most of us, regular exercise and careful attention to how many calories we eat remain the best strategies for successful and lasting weight loss.

Journal of the American College of Cardiology, Vol. 34, No. 4, pp. 1153–58.
Circulation, Vol. 100, No. 21, pp. 2161–67.

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Vitamin C: How Much Is Enough?

Vitamin C is touted as a potential weapon in combating a range of illnesses, from the common cold to cancer and heart disease.

No one believes that taking vitamin C supplements in moderate doses presents any danger, and foods rich in vitamin C (fruits and vegetables) offer real health benefits. But could consuming large amounts of vitamin C supplements be too much of a good thing?

Despite some theoretical dangers, vitamin C appears to have very few toxic effects. However, at very high doses, vitamin C can indeed cause problems. Diarrhea and abdominal bloating can result from taking several grams at once — a tactic that has been advocated by some for preventing and treating the common cold.

Studies show that high doses of vitamin C could lead to over-absorption of iron, which could potentially damage the heart, liver, and other organs. Too much vitamin C may also contribute to kidney stones or give false-positive readings on blood-stool tests. Such events occur rarely if ever, so these really are minor concerns. But, even if people are not endangering themselves much by taking large amounts of vitamin C, research suggests that they are not helping themselves either. Studies of dietary patterns show that people who get an average of 200 mg of vitamin C per day from fruits and vegetables have a lower risk of cancer — especially cancers of the mouth, esophagus, stomach, colon, and lung. Five servings of fruits and vegetables a day are enough to provide this much vitamin C. In research trials, consuming more vitamin C has not led to a detectable increase in health benefits. As for heart disease, there is evidence that marked vitamin C deficiency is associated with an increased risk of cardiovascular problems, but there is no proof that taking supplements offers additional benefits over those offered by a diet that includes the recommended amounts of fruits and vegetables.

Experts from the National Institutes of Health recently reviewed the evidence on this topic and concluded that, ideally, people should try to get their vitamin C from eating five servings of fruits and vegetables daily. Taking more than one gram (1,000 milligrams) of vitamin C per day should be discouraged because of the small, yet real, possibility of adverse effects. These recommendations do not mean that people who are taking vitamin C supplements or a multivitamin pill should stop, particularly if they just can't manage to eat enough fruits and vegetables. However, there is no reason to take high doses of vitamin C, and there may even be a small possibility of harm. For more information on vitamins and minerals, see page 43 of the Family Health Guide.

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Fish Oil Supplements Valuable for Heart Disease Sufferers

Eating like an Eskimo is believed to prevent cardiovascular disease. Now, a new Italian study has found that polyunsaturated fatty acid (fish oil) supplements significantly reduced the risk of recurrent heart troubles and related mortality in patients who had a history of heart disease.

The study involved 11,000 subjects who had survived heart attacks in the preceding three months. Researchers then monitored their progress for three-and-a-half years as they took daily doses of polyunsaturated fatty acid and vitamin E. Vitamin E, prevalent in leafy greens, is also touted for its antioxidant properties. Subjects received one of four treatments: polyunsaturated fat supplements, vitamin E supplements, both, or neither. Polyunsaturated fat supplements reduced patient mortality by nearly 20% and decreased chances of another heart attack by 10%-15%. Vitamin E, however, failed to improve survival significantly nor was there any additive effect when the two supplements were taken together. Neither supplement caused side effects.

The study might even underestimate the potential of polyunsaturated fatty acids, according to an accompanying editorial. Italians are already thought more resistant to coronary disease because of their Mediterranean diet. Results in less healthy populations might be amplified, and this could also explain vitamin E's lackluster performance. For more information on dietary fats and oils, see page 40 of the Family Health Guide.

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The Health Burden of a Few Extra Pounds

According to an extensive study conducted by the American Cancer Society, even being moderately overweight adds a significant burden to your health. This research looked at the relationship between body-mass index and the risk of death. It also examined the influence of smoking, disease, race, and age on the weight-related risk.

Body-mass index (BMI) combines height and weight measures to gauge body mass. It is calculated by dividing your weight in kilograms by the square of your height in meters. The simplest way to calculate your BMI is to use a table that lists the BMI for various weights and heights.

The study investigators followed more than one million adults between 1982 and 1996 and found that being moderately to severely overweight greatly increases a person’s chance of early death from cancer, cardiovascular disease, and other illnesses. Smoking and the presence of disease exacerbated this risk.

The lowest risk of death was associated with BMIs of 23.5 to 24.9 in men and 22.0 to 23.4 in women. Death rates then increased as BMI increased. Even exceeding the upper end of the ideal range by just a point or two appeared hazardous. The risk of death from cardiovascular disease increased significantly in men after a BMI of 26.5 and in women after 25.0 in men. And the most obese white men and women (35+ BMI) were at least twice as likely to die than their healthy cohorts. For instance, a 5 ft. 9 in. male weighing 150 pounds has a BMI of 22. Add just 30 lbs. to this person, and the BMI increases to 27, already raising his health risks. At a 35 BMI, our 5 ft. 9 in. male would weigh 240 pounds, and have increased his risk of dying from cancer by 40% and cardiovascular disease by almost 100%. Smoking and the presence of disease decreased the chance of survival regardless of the subject’s BMI.

Black Women proved the exception. Even the heaviest black women saw only a 20 –30% increase in their risk of death — opposed to the nearly 100% increase in risk for similarly overweight white women. This confirms the findings of previous studies, and could be related to differences in how the two groups of women store and process fat.

The study’s conclusion regarding the health effects of extreme leanness is more controversial. While subjects with BMIs under 18.0 experienced a moderately higher risk of death, researchers believe this was more likely a function of an unrecognized disease which resulted in lower body weight, rather that being underweight itself.

Debating the consequences of extreme leanness is academic. Only 7.7% of the US population have BMIs lower than 20. Obesity, however, is a public health threat. Nearly one- third of Americans are moderately overweight (25.0 to 29.9 BMI) and almost one-quarter are significantly overweight (30+ BMI). For more information on obesity and approaches to weight loss, see page 853 of the Family Health Guide.

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Cereal Fiber Reduces Heart Disease Risk for Women Too

Several studies have demonstrated that, for men, a high-fiber diet reduces the risk of coronary heart disease. Recently, data from the Nurses' Health Study suggests that the same is true for women.

Study investigators looked at the typical daily diet of 68,782 women. None of these women had known cardiovascular disease, cancer, high cholesterol, or diabetes at the time the study began. Researchers followed the women to see how many experienced a heart attack or died of heart disease. After adjusting for age differences among the groups, the women who ate the most fiber had a 59% lower risk of dying from coronary disease over the next 10 years when compared with women who ate the least amount of fiber. Statistical analysis indicated that each 10-gram per day increment in long-term total fiber intake was associated with a 19% reduction in coronary heart disease risk.

Researchers also found that the women with the highest long-term intake of cereal fiber had a 34% lower risk of coronary heart disease when compared with the women with the lowest consumption of cereal. Yet, the amount of fruit and vegetable fiber had little effect on heart disease risk. In fact, the benefits of cereal fiber appear to be particularly potent. An increase of five grams per day of cereal fiber was associated with a 37% reduction in heart disease risk.

The information from this report presents a particularly strong case for eating more whole grain products as a way to add fiber to your diet. You can do this by eating whole wheat bread, brown rice, and whole grain pastas, instead of the refined versions, and opting for a high-fiber breakfast cereal. Although the fiber in fruits and vegetables does not appear to lower heart disease risk, eating plenty of fruits and vegetables offers other health benefits, so these food groups should not get short shrift in anyone's diet. For more information on diet and nutrition, see page 39 of the Family Health Guide.

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Carbonated Beverages and the Risk of Bone Fractures in Teenaged Girls

Osteoporosis, or the loss of bone density, is usually thought of as a geriatric condition. But the disease may have its roots in adolescence as bone mass reaches its peak level. Factors that affect the accumulation of bone mass during this time can increase the risk of bone fractures and osteoporosis. In this context, teenaged girls may be jeopardizing their current and future health by drinking too many carbonated beverages.

Past results indicate that consumption of carbonated beverages is associated with bone fractures among teenaged girls. A recent cross-sectional study involving 460 9th- and 10th-grade girls confirmed these findings. The teenagers completed a questionnaire describing their physical activities and personal and behavioral habits. Researchers analyzed the results to determine an association between consumption of carbonated beverages and bone fractures.

Of the girls surveyed, 80% drank carbonated beverages, and nearly two-thirds of the girls drank cola. One-fifth of the girls reported having had bone fractures. Analysis showed that the risk of bone fracture in girls who drink carbonated beverages is three times that of girls who do not. The risk is highest, seven times greater, among
physically active girls who drink both cola and noncola.

The results suggest a strong association between consumption of carbonated beverages and bone fractures in teenaged girls, but the researchers caution that a cause and effect relationship cannot be assumed. Despite that, they have a few theories that may explain the association. Laboratory research has shown that the high phosphorous concentration in cola can cause bone loss that may lead to a greater risk of bone fractures. Another plausible theory is that the consumption of carbonated beverages takes the place of consumption of milk, an important source of calcium. Low calcium intake can increase the risk of osteoporosis. Between 1970 and 1997, the consumption of carbonated beverages increased by 118% per capita in the United States, while milk consumption declined 23%.

The study, however, did not include questions concerning the amounts of milk and carbonated beverages consumed. Long-term studies that include these factors may help to assess the effect of milk and carbonated beverage consumption. Also, the use of bone density measurements may demonstrate a cause and effect relationship between carbonated beverage consumption and bone fractures. Research is necessary to determine how carbonated beverages may lead to bone fractures among physically active girls. Despite the need for further studies, the current body of evidence suggests that education on the health impact of carbonated beverage consumption may be a possible way to promote optimal bone development in teenaged girls and prevent osteoporosis.

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Caution Always Key in Using Herbal Medicines

A recent study published in the New England Journal of Medicine offers another important reminder on careful use of herbal remedies. This caution is rooted in the absence of strict pharmaceutical controls in the manufacture of such products and how the lack of these requirements can leave room for tragic errors.

In the mid-1990s, doctors at a clinic in Belgium treated 43 patients with end-stage kidney failure, requiring dialysis or transplant. Not surprisingly, these individuals had something in common in their medical histories. Between 1990 and 1992, each had used a Chinese herbal remedy in combination with two other drugs for weight loss. The herbal preparation supposedly contained Stephania tetrandra and Magnolia officinalis. But the sudden appearance of kidney failure in these patients, caused their doctors to suspect that the herb Aristolochia fangchi, which is poisonous to the kidneys, had unintentionally been substituted for S. tetrandra. The Chinese names for A. fangchi and S. tetrandra sound similar and the two are often confused. Analysis showed that the herbal remedy did, in fact, contain aristolochic acids, which are derived from A. fangchi. Aristolochic acids cause cancer in rats and mutations in bacteria and mammals.

Reports of patients who had developed urothelial carcinoma (cancer of the tissues lining the bladder, ureter, and part of the kidney), as well as kidney failure related to the Chinese herbs, drew concern among the Belgian doctors. When one of their patients also developed this cancer, the doctors decided that all patients with end-stage kidney failure related to the use of Chinese herbs should be checked for cancer of these organs. By removing these organs, the doctors hoped to prevent cancer from developing in their patients. Thirty-nine of the 43 patients agreed to undergo the preventive surgery. Of these patients, 46% of them already had cancerous growths in the removed tissues. In addition, 19 of the remaining 21 patients had abnormal growths in the urinary system. The investigators also analyzed DNA samples taken from the kidneys and ureters of each patient. The DNA samples for every patient showed changes typically found after exposure to aristolochic acid. The researchers compared these results to analysis of DNA samples taken from eight patients with end-stage kidney failure unrelated to Chinese herbs. None of these control samples showed DNA changes formed by aristolochic acid.

The doctors calculated the cumulative dose of the implicated herb and other treatments for each patient. They found that the risk of cancer was related to the cumulative dose of A. fangchi. Because many of the patients had also taken appetite suppressants as well as a diuretic, the doctors noted that these drugs might enhance the toxicity of aristolochic acid.

This case study provides strong evidence suggesting a relationship between the Chinese herb A. fangchi and urothelial carcinoma. While a manufacturing mistake led to the introduction of this herb into an herbal preparation for weight loss, this study highlights the risks involved in taking herbal remedies. There is little control over the quality of herbal medicines. This means that the label on an herbal medicine may not accurately represent what is actually in the container, as was the case with S. tetrandra. Several countries have banned the use of herbs that contain aristolochic acid, yet Aristolochia is readily available in the United States in capsule form.

In the United States, the FDA does not have the authority to assess the safety and efficacy of a dietary supplement before it reaches the shelves of stores. The agency is allowed to restrict a supplement only after it proves the substance is harmful as commonly consumed, but there is no adequate system for reporting serious side effects associated with these products. Furthermore, the FDA does not have any way of knowing which herbal remedies contain harmful substances such as aristolochic acid. The case of the Chinese herbal diet pill and its association with urothelial cancer is just one of a number of cases that demonstrate the need for greater oversight of dietary supplements and caution in the use of supplements on the part of consumers.

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Healthful Diet Connected to Lower Mortality in Women

We are constantly told to eat a healthful diet — to increase fruit, vegetable, and grain intake while decreasing fat consumption. But for many of us, incorporating five fruits and vegetables into our daily routines seems impossible: they cost too much, they take too long to prepare, they contain harmful pesticides, they spoil easily. The latest study makes it easy to see the connection between a healthful diet and our own mortality — and the need to stop making the same old excuses. Simply increasing your weekly intake of 23 recommended foods could really make a difference.

Researchers from the National Cancer Institute and the City University of New York sent a food-frequency questionnaire to women who had participated in an earlier cancer study. About 50,000 women responded, but 18% were excluded because of incomplete information or answers that were deemed unreliable. The researchers were left with 42,254 participants, nearly 90% of whom were white and had 12 or more years of education. The questionnaire asked the women to indicate which of the following 23 food items they ate at least weekly: apples or pears; oranges; cantaloupe; orange or grapefruit juice; grapefruit; other fruit juices; dried beans; tomatoes; broccoli; spinach; mustard, turnip, or collard greens; carrots or mixed vegetables with carrots; green salad; sweet potatoes or yams; other potatoes; baked or stewed chicken or turkey; baked or broiled fish; dark breads like whole wheat, rye, or pumpernickel; cornbread, tortillas, and grits; high-fiber cereals, such as bran, granola, or shredded wheat; cooked cereals; 2% milk and beverages with 2% milk; and 1% or skim milk. The researchers calculated each of the women’s recommended foods score (RFS) by adding the number of items each woman checked off. The women were then divided into four groups: those who ate 0–8 of the recommended foods per week; those who ate 9–11, those who ate 12–13, and those who ate 14–23.

The women were followed up about five and a half years later, when their average age was 66. At that point, the researchers determined the number and cause of deaths within each group. After adjusting for other lifestyle factors — such as smoking status, physical inactivity, alcohol consumption, vitamin supplement use, and education — they found an inverse association between RFS and mortality from various diseases. Women who ate the most recommended foods were at 30% lower risk from dying of cancer, coronary heart disease, or stroke than those who ate the least. Even those who ate modest amounts of the recommended foods (9-11) had a decreased risk of dying from these diseases and stroke.

The study's results serve as a reminder to incorporate as many fruits, vegetables, and whole grains into our diets as possible. For nutrition strategies and an outline of the government’s Dietary Guidelines, see page 39 of the Family Health Guide.

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Calcium Carbonate's Effect on the Absorption of Levothyroxine

A recent study has revealed that calcium carbonate may reduce the body's ability to absorb the thyroid medication levothyroxine. The people who are probably most affected by this discovery are postmenopausal women, since they often end taking both levothyroxine and calcium carbonate. However, anyone taking levothyroxine and calcium carbonate concurrently can experience the same effect.

Patients participating in the study ranged in age from 27 to 78 years old and were almost evenly divided between men and women. They all had hypothyroidism (low thyroid function) and were taking levothyroxine. During the study, they were asked to take 1,200 mg of calcium carbonate daily over a three-month period. The majority of patients had significantly lower levels of thyroxine by the end of this period. They were then asked to discontinue taking the calcium carbonate, and their thyroxine levels were measured again after two months. At the end of the two-month period, their thyroxine levels were found to have returned to normal range.

In light of the fact that patients participating in the study were instructed to take the calcium carbonate daily with the levothyroxine on an empty stomach, researchers believe that the acidity level in the stomach may be a factor in how much levothyroxine is absorbed by the body. Researchers have suggested that one way to curb calcium carbonate's effect on levothyroxine is to take the calcium carbonate after a meal in order to optimize the body’s absorption of levothyroxine. They add that if while taking calcium carbonate and levothyroxine concurrently, a patient's thyrotropin level rises, it would be advisable to separate the times at which he or she takes calcium carbonate and levothyroxine on a given day. In some cases, physicians might want to increase the dosage of levothyroxine, to compensate for the effects of calcium carbonate.
October 2000 Update

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Phenylpropanolamine Safety Concerns

A recently released study reports that use of phenylpropanolamine (PPA) — an ingredient in many over-the-counter medications — is associated with an increased risk of hemorrhagic stroke (stroke caused by bleeding into the brain). Phenylpropanolamine causes blood vessels to contract, which can help relieve nasal congestion. It also stimulates the central nervous system, thereby acting as an appetite suppressant. Many cold and allergy products (for example, Contac, Sudafed, and Robitussin-CF) and diet aids (Acutrim, Dexatrim) contain PPA.

Over the past 20 years, more than 30 published case reports have linked PPA intake with bleeding in the brain. One of the earliest reports concerned a diet pill (which is no longer available) that contained both PPA and caffeine. The report’s authors concluded that PPA might cause brain bleeding more often than believed and may trigger episodes of high blood pressure. Later reports implicated products that contained only PPA. Most of these were related to PPA in diet pills, although at least five involved PPA found in cold remedies.

An epidemiological study of PPA and stroke was published in 1984. This research looked at the number of cerebral hemorrhages that occurred among HMO patients who had filled a prescription for phenylpropanolamine between 1977 and 1981. This analysis concluded that PPA users were no more likely to experience bleeding in the brain than people who hadn’t used PPA. Yet, the FDA and the manufacturers of products containing PPA agreed that more study was needed. In 1992, they commissioned the Hemorrhagic Stroke Project (HSP) in which investigators compared 702 individuals who had experienced a brain hemorrhage with 1,376 control subjects. The study volunteers included men and women ages 18-49 years old.

After researchers adjusted for the impact of race, history of high blood pressure, cigarette smoking, and educational level, they found users of cold-remedies or diet pills containing PPA were 49% more likely to have a hemorrhagic stroke when compared to individuals who had not taken PPA. Users of PPA in cold medicines (but not diet pills) had a 23% higher risk of hemorrhagic stroke when compared to non-users.

PPA consumed in diet pills increased that risk substantially, however, being 15 times greater for users than nonusers — even after statistical adjustments. For women, the association between PPA in appetite suppressants and hemorrhagic stroke was 17 times higher (after statistical adjustment) for users versus nonusers. For first dose PPA users, the statistically adjusted risk for brain bleeding was three times greater than for controls.

Study investigators also observed that bleeding in the brain was more likely to occur in people who took greater than the median dose (75 mg). Interestingly, when compared to control subjects, case subjects were significantly more likely to have other risk factors for hemorrhagic stroke. For example, they were nearly twice as likely to have a history of high blood pressure, a family history of hemorrhagic stroke, heavy alcohol use, and were also more likely to report cocaine use. The PPA users were more likely to have taken aspirin (which may raise hemorrhagic stroke risk) and more than twice as likely than controls to have consumed caffeine and more than 10 times as likely to have had recent nicotine exposure. Like PPA, caffeine and nicotine also constrict blood vessels, perhaps exaggerating this effect and contributing to bleeding risk.

Certainly, this research strongly suggests that taking PPA in diet pills might increase hemorrhagic stroke risk. Because weight loss achieved through the use of these drugs is not apt to be healthy or long lasting, there is little to justify the apparent increased risk of using PPA-containing diet pills. The associated risk for stroke with PPA use in cold medicines is not as dramatic, yet these data are a sobering reminder to take seriously the directions and warnings on products containing PPA. Specifically, people with heart disease and high blood pressure should not take PPA without consulting their doctors. Individuals who take monoamine oxidase inhibitors (used for depression, psychiatric or emotional conditions, and Parkinson’s disease) — or who have stopped taking them only within the last two weeks — also should not take products containing PPA until they clear it with their physicians. Finally, these data bring home the message that over-the-counter drugs are drugs, and like prescription medications, they come with potential risks and side effects.

Right now it is uncertain whether the FDA will vote to restrict medications with PPA to prescription-only status, but it is taking these results under advisement.

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Surgery for Severe Obesity

Two recent studies offer some hope for people who suffer from "clinically severe obesity" (generally, a body mass index greater than 40). For these people, whose weight poses serious health risks, conventional diet and drug interventions are usually unsuccessful. A last resort has been surgery to limit the number of calories the body absorbs. But there have always been concerns about the benefits versus the risks of surgery. Two procedures, the Roux-en-Y gastric bypass and adjustable laparoscopic gastric banding, each appear highly effective at promoting weight loss in obese individuals.

In the Roux-en-Y gastric bypass procedure, surgeons divide the patient’s stomach in two and create a small pouch from the upper stomach. They then connect the small intestine directly to this pouch, bypassing the rest of the stomach. When the patient eats or drinks, the food passes from the esophagus into the small pouch, which can hold only two to three ounces. Because the pouch is so limited, the person feels full and satisfied after eating only a small amount of food.

In a study conducted through the Mayo Clinic, surgeons performed the gastric bypass procedure on obese patients and found that after one year, the patients followed up had lost 68% of their excess body weight. This weight loss remained fairly consistent over four years. Many patients also reported that their appetites had decreased. As an added benefit, a number of individuals were able to reduce their high blood pressure, diabetes, and anti-inflammatory medications. Yet some patients in the study suffered complications from the surgery, such as wound infection, hernias, and bowel obstruction. Despite this, the procedure proved to be successful overall. After three years, 93% of the patients contacted were satisfied with the results.

Traditionally, gastric bypass is performed through a long incision in the patient’s abdomen. Doctors at the Lahey Clinic have eliminated the need for the long incision through the use of laparoscopic techniques during surgery. The surgeons make six half-inch-long incisions in the abdomen through which they can use surgical instruments and a laparoscope to view the abdominal cavity. The Lahey Clinic reports that this technique results in weight loss similar to the traditional surgical technique, yet is safer and less invasive — patients recover more quickly and do not have the risk of complications associated with a long incision.

The other procedure for obesity that boasts good results is adjustable laparoscopic gastric banding. With this technique, surgeons use a laparoscope to place an adjustable silicone band around the stomach, forming two pouches. As with the bypass technique, patients with the band feel full after eating a small amount of food because the first pouch of the stomach is small. In addition, the narrow passageway between the two pouches slows down the transfer of food. Doctors can use radiography to view the condition of the band and, if needed, can adjust the size of the passageway between the two pouches by injecting or aspirating a saline solution into a tube connected to the band.

In a Swiss study, patients who underwent the banding procedure lost an average of 14% of their total weight six months after the procedure and 18% after twelve months. These results sound great, but complications, such as problems with the band, were frequent, occurring in 34 out of 98 patients. Despite that, the study claims that complications led to unsatisfactory weight loss in only one of the patients. Nineteen other patients did not lose significant amounts of weight as a result of poor compliance.

As with any weight loss treatment, both gastric bypass and banding surgery require that the patient adopt new eating habits. Physicians must also monitor these patients to make sure that they do not develop vitamin and mineral deficiencies. But given the apparent success of each technique, surgery for clinically severe obesity may be an attractive alternative to diet and drug intervention, despite the risks involved. (10.30.00)

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©2000–2006 President & Fellows of Harvard College
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