Skip Navigation Bar
NIH MedlinePlus the Magazine, Trusted Health Information from the National Institutes of Health

Pressure Points: Preventing and Controlling Hypertension

Four people walking on the beach.

May is National High Blood Pressure Education Month, a good time for many Americans to make sure that they and their loved ones are protected against this silent killer.
Photo: iStock

Nearly one in three adults—almost 65 million Americans—suffers from hypertension, or high blood pressure. What's more, high blood pressure leads to more than half of all heart attacks, strokes and heart failure cases in the United States. It also increases the risk of kidney failure, blindness and other serious health consequences.

Faced with such alarming statistics and based on a landmark 2002 study called the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT), the National Institute of Health's National Heart, Lung, and Blood Institute (NHLBI) has begun a comprehensive, nationwide educational outreach program to better identify and treat high blood pressure.

"It often takes years for the results of major studies to become part of standard healthcare," says NHLBI Director Elizabeth G. Nabel, M.D. "The results of ALLHAT and the clinical guidelines could have an enormous impact on the health of millions of Americans. By aggressively sharing this information, we will be able to put the results into action more quickly and more effectively."

Throughout May, which is National High Blood Pressure Education Month, physicians and communities across the country will be taking part in the activities planned to inform the public how to recognize and treat hypertension.

Living by the Numbers

For patients and their families alike, it is critical to understand the basics in order to be able to better control the disease.

Simply put, blood pressure is the force exerted by blood on the walls of the arteries and veins as it courses through the body. Like the ocean tide, it is normal for blood pressure to rise and fall throughout the day. But when the pressure stays elevated over time, it causes the heart to pump harder and work overtime, possibly leading to various, serious health problems, ranging from hardening of the arteries, stroke and brain hemorrhage to kidney malfunction and blindness.

Blood pressure is recorded as two numbers, the systolic (pressure during a heartbeat) over the diastolic (pressure between heartbeats). For example, a measurement of 120/80 millimeters of mercury (mmHg) is expressed as "120 over 80." Normal blood pressure is less than 120/80. People with pressures between 120/80 and 139/89 are considered to have pre-hypertension and be likely to develop high blood pressure without preventative measures.

Today, clinical guidelines recommend that physicians work with patients to keep their blood pressures below 140/90 mmHg, and even lower for people with diabetes or kidney ailments. In all cases, patients are encouraged to lose excess weight, exercise regularly, not smoke, limit intake of alcoholic beverages, and follow heart-healthy eating plans, including cutting back on salt and other forms of sodium.

Assessing Your Risk

While many Americans develop high blood pressure as they get older, it is not a hallmark of healthy aging. This is especially critical for African-Americans, in whom the disease tends to begin at an earlier age and be more severe. In addition to being at increased risk, they also experience higher rates of death from stroke and kidney disease than does the general population.

As the following examples illustrate, the indicators for high blood pressure vary widely from individual to individual and bear very close, personal vigilance.

  • Ron Tucker, a 42-year-old African-American suffering from hypertension, is always on the go. His biggest challenge to lowering his blood pressure is to watch what he eats, especially fast food. "African-Americans are very sensitive to salt," he says, "so I've got to be more careful, especially at lunch when I usually grab a burger and fries. Besides the fat, that meal has lots of salt."
  • Carol Jackson, 42 and white, has thus far managed to avoid a diagnosis of high blood pressure although her readings do fall within the prehypertension range, putting her on notice. Further reasons to remain on guard include a family history of high blood pressure, lack of regular exercise and the fact that she smokes. "My mother and father both had high blood pressure, and my father passed away from a stroke when he was only 59," she says.

By adopting healthier lifestyles, Tucker, Jackson and the millions more facing hypertension can begin controlling their conditions. "Don't wait until your pressure spikes to make changes," urges Lawrence Appel, M.D., M.P.H., lead author of a February 2006 report in Hypertension: Journal of the American Heart Association, which links healthier eating habits to lowered blood pressure.

"While an individual's blood pressure may be normal now, 90 percent of Americans over 50 years of age have a lifetime risk of high blood pressure," says Appel, a professor at Johns Hopkins University School of Medicine. "Americans should take action before being diagnosed with high blood pressure."

An Ounce of Prevention

For example, because blood pressure rises as body weight increases (and obesity is a known risk factor for developing high cholesterol and diabetes, which in turn can lead to heart disease), a loss of little as 10 pounds can help to lower blood pressure.

Two recent studies confirm the blood pressure benefits of maintaining a healthy diet. First is the Dietary Approaches to Stop Hypertension (DASH) clinical study, which tested the effects of food nutrients on blood pressure. It emphasizes consumption of fruits, vegetables and lowfat dairy foods, whole grains, poultry, fish and nuts, and stresses reduction of fats, red meats, sweets and sugared beverages.

Second is the DASH-sodium study, which demonstrates the importance of lowering sodium intake. Most Americans consume far more than the current, daily recommendation of 2,400 milligrams (mg) of sodium—about a teaspoon of table salt—or less. This includes all salt and sodium consumed, not just at the table, but also in cooking. For those with high blood pressure, consuming even less may be advisable, since the DASH-sodium study revealed that diets containing no more than 1,500 mg of sodium per day had still greater pressure-lowering effects.

Regular physical activity is another good step toward controlling or even preventing high blood pressure. Start with 30 minutes of moderate-level activity, such as brisk walking, bicycling or gardening on most—preferably all—days of the week. The activity even may be divided into three, 10-minute periods each. For added benefit, these moderate half-hours may be increased or supplanted by regular, vigorous exercise. Of course, prior to upping the activity level, people should check with their physicians, especially if they have had heart trouble or a previous heart attack, a family history of heart disease at an early age or other serious health problems.

Another healthy move is to limit alcohol intake. Excess alcohol can raise blood pressure as well as damage the liver, heart and brain. Drinks should be kept to a maximum of one per day for women, and two for men. (One drink equals 12 ounces of beer or five ounces of wine.)

Finally, quit smoking. Among other things, smoking damages blood vessel walls and speeds hardening of the arteries. Ceasing smoking reduces the risk of heart attack in just one year.

Taking Control

High blood pressure is a silent killer, often with no obvious or visible symptoms. The only way to find out if you have hypertension is through testing by your physician, who will make the diagnosis on the basis of two or more readings taken on different visits.

For much more information on high blood pressure, log onto the NIH Medline Plus Web site (, the free, consumer-friendly health and medical resource featuring thousands of definitions, encyclopedia articles, interactive tutorials and clinical trials.

Read More "Preventing and Controlling Hypertension" Articles

Pressure Points: Preventing and Controlling Hypertension / Hypertension — Listen to Your Heart

Summer 2006 Issue: Pages 11 - 13