What is hypertension?
Every time you get your blood pressure checked, you get two numbers, perhaps something like 130/85. These numbers tell you how hard your blood pushes against the walls of your arteries as it flows through your body. The higher figure, called systolic pressure, indicates the force pushing on blood vessels as the heart contracts. The lower figure, called diastolic pressure, shows the force when the heart relaxes.
Whether you're a card player or tennis player, a healthy blood pressure reading is below 120/80. There's no single cutoff between healthy and unhealthy numbers, but high blood pressure is now defined as 130-139 over 80-89. In these ranges, both the heart and arteries are straining too hard to move blood. This condition is called hypertension or high blood pressure, and it affects about one in three U.S. adults.
Even if your blood pressure is 120/80, you should still keep an eye on it. This category is considered prehypertension, and according to the NHLBI, you should be sure to exercise regularly, eat plenty of fruits and vegetables, and live a heart-healthy lifestyle to prevent your blood pressure from going any higher.
American Heart Association/American Stroke Association
Is hypertension dangerous?
Hypertension is a major contributor to some of the most dangerous diseases in our country. Compared to a person with normal blood pressure, someone with hypertension is more than twice as likely to develop heart disease and six times more likely to have a stroke. High blood pressure can cause blindness and also severely damage your kidneys.
What causes hypertension?
Some people develop high blood pressure during pregnancy or because of hormone imbalances or an illness such as kidney disease. But for most people, hypertension can't be traced to a single cause. Doctors do know, however, that some things make the condition much more likely. A family history of hypertension doubles your chances of having it. High blood pressure is also more common in older people. Anyone who doesn't exercise, is overweight, drinks too much alcohol, or, in some cases, eats too much salt is at the risk of developing hypertension.
Contrary to popular belief, coffee does not appear to contribute to hypertension, at least not in women. A 12-year study of more than 150,000 women published in the Journal of the American Medical Association (JAMA) found neither caffeinated nor decaf coffee contributed to long-term hypertension and, ironically, that drinking coffee might actually decrease the risk of hypertension.
The study cautioned, however, that other caffeinated beverages, such as soft drinks and tea, do appear to increase the risk of hypertension. Women who drank more than three cans of cola per day, for instance, were up to 44 percent more likely to be diagnosed with hypertension than those who drank only one.
Stress can temporarily boost high blood pressure. For instance, some people have short-term hikes in pressure whenever they visit a doctor's office. When it comes to controlling blood pressure, stress is a much less important factor than diet or exercise. If you continually feel a lot of stress, however, it's useful to explore such stress-reduction measures as yoga, progressive relaxation, and meditation.
Can children have hypertension?
Yes. 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, the government released federal guidelines recommending 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.
How can I tell if I have hypertension?
Many people with hypertension don't even know they have it. Blood pressure usually rises gradually, and you're not likely to notice any symptoms even as your pressure climbs to dangerous levels.
That's why it's important to get your pressure checked regularly even if you feel fine. If you've always had normal blood pressure, you should get checked every two years. If your last reading was borderline high or if your age, lifestyle or family history puts you at risk for the condition, have your pressure checked at least once a year.
How can I keep my blood pressure low?
Whether you already have hypertension or simply want to keep your pressure down, a few healthy lifestyle changes can make a big difference:
Stay active. Any regular exercise that gets the heart pumping faster, such as brisk walking, can take points off your blood pressure and strengthen your heart. Blood pressure actually rises slightly during a workout, but it eventually finds a lower resting place. However, high-resistance exercises such as lifting heavy weights can lead to long-term increases in blood pressure. If you want to build strength, use moderate weights. (If you haven't exercised in a while, check with your doctor.)
Eat less saturated fat. If you like hamburgers, cheese, and whole-fat milk, adopting a low-fat, low-cholesterol diet will probably reduce your blood pressure at least slightly. More important, switching to a leaner diet will definitely help prevent clogged arteries and heart attacks. "Good" fats like olive oil omega-3 fatty acids found in fish are good for your heart, too.
If you smoke, stop. Cigarettes can damage the heart and arteries and greatly increase the risk of heart attack and stroke. A person who manages to lower his blood pressure but still smokes has won only half of the battle.
Stay trim. Blood pressure tends to rise with extra weight. Heavy people with hypertension can drop almost one point from their pressure for every two pounds lost.
Eat more produce. Most fruits and vegetables contain potassium, a mineral that seems to lower blood pressure. Orange juice, tomato juice, bananas, and potatoes are all high in potassium; some studies have shown, in fact, that eating two bananas a day may lower blood pressure significantly. Try to eat the recommended daily allowance of eight to 11 servings of fruit and vegetables.
Cut back on salt. This advice isn't for everyone. About 58 percent of the people with high blood pressure are salt sensitive. The rest will hardly nudge their pressure by eating less salt. The best way to find out if you're salt sensitive is to talk to your doctor about trying a low-salt diet for two weeks to see if your pressure drops. Remember that packaged meals, canned foods and fast food can be much bigger sources of salt in your diet than the shaker.
Drink sensibly. One alcoholic drink a day or less may lower your blood pressure and protect your heart, but drinking much more will raise your blood pressure. Federal health agencies say that a sensible limit is two drinks a day or less for men and one drink a day or less for women; however, even this low level of drinking may increase the risk of various illnesses, including some cancers, according to the CDC. (A drink is defined as the amount of alcohol in 12 ounces of regular or light beer, 5 ounces of wine, and 1.5 ounces of distilled spirits, or hard liquor.) Alcoholism in itself can also be a cause of hypertension.
Track your pressure. People with hypertension should keep tabs on their condition. If you have severe hypertension, you may want to get a blood pressure monitor to use at home periodically. With repeated measurements in a relaxed setting, you'll learn your average pressure and be able to tell if your lifestyle changes are working.
Seek treatment for depression or chronic anxiety. Researchers at the Centers for Disease Control and Prevention completed a study that indicates depression and anxiety can more than double a person's risk of developing high blood pressure. Consult your physician for advice.
How is high blood pressure treated?
Before filling out a prescription for medication, your doctor will probably want you to first tackle the problem by exercising regularly, trying to lose excess weight, and cutting back on saturated fats, alcohol, and possibly salt. If your blood pressure remains high, it may be time to consider medication. Be sure to talk with your doctor about possible side effects and drug interactions.
Remember, however, that hypertension drugs should always be accompanied by a healthy lifestyle. By exercising and eating right, you may someday be able to control your blood pressure without taking medication.
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Wolfgang C. Winkelmayer, MD, et al. Habitual Caffeine Intake and the Risk of Hypertension in Women. JAMA; 294:2330-2335.
National Institutes of Health. Study Shows New Link Between Salt Sensitivity and Risk of Death. http://www.nhlbi.nih.gov/new/press/01-02-15.htm
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