Lose Weight and Keep It Off

How excess weight affects your health

If you’re carrying many extra pounds, if you face a higher than-average risk of a whopping 50 different health problems  These health conditions include the nation’s leading causes of death—heart disease, stroke, diabetes, and certain cancers—as well as less common ailments, such as gout and gallstones. Perhaps even more compelling is the strong link between excess weight and depression, because this common mood disorder can have a profound negative impact on your daily life.

A Harvard study that combined data from more than 50,000 men (participants in the Health Professionals Follow-up Study) and more than 120,000 women (from the Nurses’ Health Study) revealed some sobering statistics about weight and health. The volunteers provided their height and weight, as well as details on their diets, health habits, and medical histories. Researchers tracked the volunteers over more than 10 years, noting the occurrence of illnesses and comparing those developments with each subject’s BMI.

Obesity increased the risk of diabetes 20 times and substantially boosted the risk of developing high blood pressure, heart disease, stroke, and gallstones. Among people who were overweight or obese, there was a direct relationship between BMI and risk: the higher the BMI, the higher the likelihood of disease.

Heart disease and stroke

Some of the most common problems seen in people who carry excess weight tend to occur together, such as high blood pressure and unhealthy levels of cholesterol and other fats in the blood. And both can lead to concurrent health problems—namely, heart disease and stroke. High blood pressure is about six times more common in people who are obese than in those who are lean. According to the American Heart Association, 22 pounds of excess weight boosts systolic blood pressure (the first number in a reading) by an average of 3 millimeters of mercury (mm Hg) and diastolic blood pressure (the second number) by an average of 2.3 mm Hg. That translates to a 24% increase in stroke risk.

A 2007 study in the Archives of Internal Medicine examined the connection between weight and heart disease by pooling results from 21 different studies involving more than 300,000 people. Being overweight boosted the risk of heart disease by 32%, whereas obesity increased the risk by 81%, the researchers found. Although the adverse effects of overweight on blood pressure and cholesterol levels could account for 45% of the increased heart disease risk, even modest amounts of excess weight can increase the odds of heart disease independent of those well-known risks, the authors concluded. Compared with people of normal weight, overweight people face a 22% higher risk of stroke. For those who are obese, the increased risk rises to 64%, according to a 2010 report in the journal Stroke, which pooled results from 25 studies involving more than two million people.

Diabetes

Overweight and obesity are so closely linked to diabetes that experts have coined the term “diabesity” to describe the phenomenon. About 90% of people with type 2 diabetes (the most common form of the disease) are overweight or obese. The incidence of diabetes rose dramatically—by nearly 65%—from 1996 to 2006. A high blood sugar level, the hallmark of diabetes, is one of the features of metabolic syndrome. If untreated or poorly controlled, diabetes can lead to a number of grave health problems, including kidney failure, blindness, and foot or leg amputations. Diabetes is currently the seventh leading cause of death in the United States.

Cancer

Some experts believe that obesity ranks as the second leading cause of cancer death, after cigarette smoking. A study by the American Cancer Society in the New England Journal of Medicine that followed more than 900,000 people for 16 years showed a link between excess body weight and many different cancers. Among people ages 50 and older, overweight and obesity may account for 14% of all cancer deaths in men and 20% of all cancer deaths in women. In both men and women, higher BMIs were associated with a higher risk of dying from cancer of the esophagus, colon and rectum, liver, gallbladder, pancreas, or kidney. In men, excess weight also increased the risk of dying from stomach or prostate cancer. In women, deaths from cancer of the breast, uterus, cervix, or ovary were elevated in women with higher BMIs. A 2008 review article in The Lancet reached similar conclusions.

Part of the problem may lie in the fact that people who are very overweight are less likely to have cancer screening tests such as Pap smears and mammograms. A report in the International J Journal of Obesity showed that the larger the woman, the more likely she was to delay getting a pelvic exam, largely because of negative experiences with doctors and their office staff. In men, screening tests such as prostate exams may be physically difficult if people are very overweight, particularly if they tend to store fat in their hips, buttocks, or thighs.

Depression

Do people gain weight because they’re depressed, or do they become depressed because they have grown overweight? A review of 15 studies found evidence that both scenarios are likely true. Obese people have a 55% higher risk of developing depression over time compared with people of normal weight, according to a 2010 study in the Archives of General Psychiatry. Both conditions appear to stem (at least in part) from alterations in brain chemistry and function in response to stress. But psychological factors are also plausible. In our culture, thin equals beautiful, and being overweight can lower self-esteem, a known trigger for depression. Also, odd eating patterns and eating disorders, as well as the physical discomfort of being obese, are known to foster depression.

The study also found that depressed people have a 58% higher risk of becoming obese. According to one theory, elevated levels of the stress hormone cortisol (common in people with depression) may alter substances in fat cells that make fat accumulation, especially in the belly, more likely. Also, people who feel depressed oft en feel too blue to eat properly and exercise regularly, making them more prone to gain weight. And finally, as mentioned earlier, some medications used to treat depression cause weight gain.