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Get your copy of Hypertension: Controlling the "silent killer" An alarming one in three American adults has high blood pressure. Known medically as hypertension, many people don't even know they have it, because high blood pressure has no symptoms or warning signs. But when elevated blood pressure is accompanied by abnormal cholesterol and blood sugar levels, the damage to your arteries, kidneys, and heart accelerates exponentially. Fortunately, high blood pressure is easy to detect and treat. Sometimes people can keep blood pressure in a healthy range simply by making lifestyle changes, such as losing weight, increasing activity, and eating more healthfully. Click here to read more »

The hidden burden of high blood pressure

A silent condition like high blood pressure is sneaky. It generally doesn’t cause any outward signs or symptoms, and yet it relentlessly causes problems in the arteries, heart, kidneys, and elsewhere.

High blood pressure — also known as hypertension — isn’t a disease. It is a sign that something is wrong in the body. In some people with hypertension, the culprit is a narrowing of the arteries supplying the kidneys (renal artery stenosis), or an overactive thyroid gland (hyperthyroidism) or adrenal glands (aldosteronism). If these are treated, blood pressure drops back to normal. Most of the time, though, no immediate cause can be identified. Doctors call this essential hypertension.

Effects on health

High blood pressure imposes an up-front burden in people who know they have it and who are working to control it. It adds to worries about health. It alters what you eat and how active you are, since a low-salt diet and exercise are important ways to help keep blood pressure in check. High blood pressure often requires you to take one or more pills a day, which can be a costly hassle.

There are long-term consequences, too. High blood pressure contributes to the development of stroke, heart attack, heart failure, and kidney disease. In the United States, it directly accounts for about 60,000 deaths a year and contributes to another 300,000.

Then there are hidden burdens. Perhaps because of all the ways hypertension interferes with health, the average life span for people with it is five years shorter than it is for those with normal blood pressure. A team of Spanish researchers has tallied up another hidden drain of high blood pressure — its effect on survival and rehospitalization after someone is admitted to the hospital for a heart problem.

The researchers looked at 1,007 men and women admitted to the hospital over a 10-month period for any potentially heart-related problem. These ranged from chest pain and fainting to heart attack, heart failure, atrial fibrillation, and pericarditis. In this group, 69% had been diagnosed with high blood pressure before being admitted to the hospital.

Each person was followed for one year. At the end of that time, 17% of those with high blood pressure had died, compared with 9% of those with normal blood pressure. Rehospitalization for a cardiac problem followed the same pattern: 31% of those with high blood pressure were rehospitalized, while only 18% of those without it were.

Keeping the burden at bay

It is possible to blunt the effects of hypertension by keeping blood pressure in check with medications and lifestyle choices. Preventing it from getting started is even better.

How? The National Heart, Lung, and Blood Institute; the Centers for Disease Control and Prevention; and the American Heart Association offer these recommendations:

• Control your weight.
• Exercise regularly.
• Follow a diet that is rich in fruits, vegetables, and whole grains.
• Limit sodium intake to under 2,300 milligrams a day (one teaspoon of salt), and get plenty of potassium (at least 4,700 mg per day) from fruits and vegetables.
• Drink alcohol in moderation, if at all.
• Reduce stress.
• Check your blood pressure.

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Get your copy of Vitamins and Minerals: Choosing the nutrients you need to stay healthy About half of all Americans routinely take dietary supplements, the most common being multivitamin and multimineral supplements. This report explains the different types of studies used to assess the benefits and safety profiles of various nutrients. It also includes the recommended minimum and maximum amounts of the vitamins and minerals you should consume, as well as good food sources of each. Click here to read more »

Should I have my magnesium level checked?

Q. Should I have my magnesium level checked regularly to make sure I’m getting enough for my bones?

A. Adequate magnesium is central to hundreds of biochemical reactions throughout the body and essential for proper nerve, muscle, heart rhythm, and immune function as well as bone health. It also helps regulate blood sugar levels and promotes healthy blood pressure.

We get most of the magnesium we need from food (good sources are whole grains, legumes, and dark-green leafy vegetables). Most multivitamins also contain some magnesium.

Magnesium is absorbed in the intestine and travels through the blood to cells and tissues; any excess is excreted through the kidneys. About half of the magnesium we absorb is stored in bone; the other half, in cells throughout the body. Only a little is found in blood. As a result, the blood level of magnesium doesn’t tell us much about the body’s total store of the mineral.

Magnesium deficiency, which is rare in the United States, can cause muscle weakness, cramping, or heart rhythm disturbances. Conditions that impair absorption, such as chronic vomiting, Crohn’s disease (an inflammatory condition of the intestine), celiac disease, and gastric bypass surgery, can lead to magnesium deficiency.

For women ages 31 and over, the recommended dietary allowance of magnesium is 320 milligrams (mg) per day (360 mg/day for pregnant women).

If you’re otherwise healthy, your magnesium level is probably normal and you don’t need to check it regularly. It’s much more important to make sure that you’re including whole grains, dark-green leafy vegetables, and legumes in your diet.

— Celeste Robb-Nicholson, M.D.
Editor in Chief, Harvard Women’s Health Watch