By Chris Woolston, M.S.
Is your blood pressure discriminating against you?
Like so many other things, blood pressure is a mixture of luck and lifestyle. While some people seem to have low pressure by nature, others are predisposed to dangerously high numbers. But no matter what hand you're dealt, it's likely that you have the power to lower your blood pressure.
About 73 million Americans have high blood pressure (defined as a reading 140/90 or higher), which increases your chance of having a heart attack, stroke, and kidney failure, according to the National Institutes of Health. But even if your blood pressure is below 140/90, you may still be at risk. According to guidelines issued by the National Heart, Lung, and Blood Institute (NHLBI), blood pressure that falls between 120-139/80-89 is now considered "prehypertension." If your numbers fall in this range, says the NHLBI, you should check your risk factors for high blood pressure and make any necessary lifestyle changes.
As you'll see, many of these risk factors are under your control. Whether your overall risk is high or low, you can always take steps to keep your pressure down and protect your health.
Experts estimate that up to 75 percent of cases of hypertension in industrialized countries can be traced directly to obesity. Overall, obese people (those who are at least 30 percent over their ideal weight) are two to three times more likely than others to have high blood pressure, according to the American Medical Association.
Unfortunately, many overweight people are also inactive, another major risk factor for high blood pressure. Add in a diet high in salt and low in nutrient-rich fruits and vegetables, and you have an ideal recipe for high blood pressure.
Level of activity
Regular exercise is one of the most reliable ways to lower your blood pressure. At the other end of the spectrum, being inactive invites trouble. The American Heart Association recommends getting at least 30 minutes of moderate physical activity five days of the week or more, or at least 20 minutes of vigorous aerobic activity three days a week. That's not as difficult as it sounds. The organization notes that you can accumulate your 30 minutes in bouts of brisk 10-minute walks throughout the day if you are pressed for time.
A diet rich in fruits and vegetables provides strong protection against high blood pressure, according to the American Journal of Clinical Nutrition. Much of the credit seems to go to potassium, a vital mineral for cardiovascular health. On the other hand, a diet with a heavy emphasis on salt-laden foods can make pressure rise. Not everyone is sensitive to salt, but there's no easy way to tell who's at risk. To be safe, you should follow the U.S. Department of Agriculture's Dietary Guidelines for Americans and consume no more than 2,300 milligrams of sodium each day. If you are African-American, have hypertension, or are middle-aged or older, you should have no more than 1,500 mg of sodium a day.
For unknown reasons, heavy drinking almost always boosts blood pressure. An increase in pressure is especially likely among people who have four or more drinks each day. The American Heart Association recommends no more than two alcoholic drinks per day for men and one drink per day for women.
Blood pressure often rises steadily with age. More than two-thirds of adults over the age of 60 have high blood pressure, according to the National Center for Health Statistics. In part, this climb may be a natural consequence of aging. As arteries stiffen over time, plaque can build up inside them and blood pressure tends to rise.
But high blood pressure isn't as inevitable as wrinkles and thinning hair. The link between age and blood pressure can be largely explained by lifestyle. Many people become less and less active as they age. At the same time, their waistlines may grow with the years. Longtime over-use of alcohol or a diet rich in salt can also lead to high blood pressure later in life, the National Institute on Aging warns.
High blood pressure isn't just a disease for the elderly. In recent years, a younger generation of Americans, including children in their teenage years, has seen its blood pressure rise as a growing number of them become overweight. Researchers blame the higher blood pressure readings on lack of exercise, poor eating habits, and excess weight.
In response to the problem, federal guidelines recommend blood pressure checks for children over the age of 3 during routine office visits. A reading over the 95th percentile for the child's size and age would be considered to be hypertension, and a reading between the 90th and 95th percentile would be considered prehypertension. Doctors say that children may be able to avoid both labels entirely by pursuing healthy lifestyles with regular exercise and a low-fat diet rich in fruits and vegetables.
For reasons that aren't entirely clear, young men are more likely than young women to have high blood pressure. By the time they reach their middle 50s, the risk is about even. As the years go by, women begin to take the lead. At age 75 and beyond, hypertension is significantly more common in women than in men.
Genetics and race
There's evidence that African Americans are stricken more frequently with hypertension than Caucasians. In fact, up to 41 percent of African Americans suffer from the condition, compared with 28 percent of Caucasian Americans, and 22 percent of Mexican Americans, according to the Centers for Disease Control. Genes offer one easy explanation. Perhaps, as a popular theory goes, black people are just naturally inclined toward high blood pressure. If that were the whole story, most people of African descent would have high blood pressure. But surveys conducted by the authors of the Scientific American article found that high blood pressure is almost unheard of in West Africa, to which most African Americans can trace their roots.
People of African heritage may well be genetically inclined toward high blood pressure, but it takes a certain environment to unlock that potential. African Americans who get regular exercise, keep their weight down, and go easy on salt and alcohol have a good chance of avoiding hypertension. Regardless of race, though, if one or both of your parents have high blood pressure, your risk increases.
You can't choose your race, age, or gender, but by working to change the things within your control, you can go a long way toward protecting yourself from high blood pressure.
New recommendations to prevent high blood pressure, Science Daily, Jan. 31, 2011
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American Heart Association. High blood pressure statistics. http://www.americanheart.org/presenter.jhtml?identifier=4621
Cooper, Richard S et al, The Puzzle of Hypertension in African-Americans. Scientific American. February 1999.
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National Heart Lung and Blood Institute. Who Is at Risk for High Blood Pressure? http://www.nhlbi.nih.gov/health/dci/Diseases/Hbp/HBP_WhoIsAtRisk.html
Centers for Disease Control. Health, United States, 2005, Table 67. http://www.cdc.gov/nchs/data/hus/hus05.pdf
American Heart Association. Physical Activity and Public Health: Updated Recommendations for Adults from the American College of Sports Medicine and the American Heart Association. Circulation. 2007 Aug 1; 116: 1081-1093.
US Department of Agriculture. Dietary Guidelines for Americans, 2005. http://www.health.gov/dietaryguidelines/
National Center for Health Statistics. Hypertension Awareness, Treatment, and Control: Continued Disparities in Adults: 2005-2006. NCHS Data Brief No. 3. January 2008. http://cdc.gov/nchs/data/databriefs/db03.pdf
Last Updated: March 11, 2013
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