The word hypertension brings to mind images of stressed-out stockbrokers shouting in the bidding den. In reality, the term doesn't refer to nervous tension, but rather to arterial blood under excessive pressure, hence the common name, high blood pressure. Arterial blood pressure has two measurements. The first, called systolic pressure, represents the force against the arteries as the heart pumps out blood. The second, called diastolic pressure, represents the pressure in the arteries as the heart relaxes between beats. The systolic pressure is given first, then the diastolic. Most health practitioners consider normal blood pressure to hover around 120/80 (spoken of as 120 over 80). Although blood pressures under 140 systolic and 85 diastolic are generally acceptable, there is evidence that any elevation over 80 diastolic may increase the risk of cardiovascular diseases. These diseases include the most common killers in Western cultures: stroke, arteriosclerosis and congestive heart failure.

Without the aid of a blood pressure cuff, a person generally can't tell whether hypertension is a problem. Most people aren't aware of their elevated blood pressure until after they've developed heart disease or had a stroke. Because of the dearth of associated symptoms, hypertension has been called the "silent killer." It's a scary term. In the past, radio public service announcements capitalized on this fear factor, saying that patients could never safely stop their blood pressure medications. And who supported these announcements? The manufacturers of blood-pressure-lowering medications.

The truth is that under supervised medical care, hypertensive patients can do many things to reduce or eliminate the need for medication. The first step is identifying the cause. Sometimes problems such as kidney disease, hormone disorders, neurological conditions and certain medications have led to the high blood pressure--a condition called secondary hypertension. Curing the underlying condition can bring blood pressure back to normal.

When no known disease process has caused the high blood pressure, it's called primary or essential hypertension. Primary hypertension accounts for more than 90 percent of all cases of high blood pressure.1 Lifestyles associated with poor diet, lack of physical activity, stress and obesity all contribute to high blood pressure.2-4 Managing the condition involves improving lifestyle habits and boosting the diet with nutritional supplements.

Prevention And Treatment Diet: Many experts consider the standard American fare our downfall. Eating foods high in fat, sugar, sodium, preservatives and additives and low in many nutrients leads to many health problems, including hypertension.

For example, in one study, hypertensive rats fed sugar, without changing their salt intake, had 10 percent increases in their blood pressure.5 Another study in humans reported that adding sucrose or glucose to the diet elevated blood pressure and increased salt retention.6

The healthiest diet for almost any health problem, including hypertension, is the high-fiber, high-complex-carbohydrate, mostly vegetarian fare typically consumed by nonindustrialized cultures. When medical researchers studied African populations, they found the people relatively free of cardiovascular disease, bowel cancers and many other health problems. Their dietary staples consisted largely of potatoes, bananas, corn meal and beans.7 Clinical studies have shown that a whole-foods, plant-based diet can reverse heart disease and diabetes, and reduce the risk of cancer and the symptoms of arthritis.8,9

A solely plant-based diet can also lower blood pressure.10 Compared to omnivores, ovolactovegetarians (people who consume eggs and dairy, but no flesh) tend to have lower blood pressures. Even a relatively small reduction of systolic blood pressure can significantly reduce the risk of heart disease.11

In one study, more than 30,000 American male health professionals without hypertension were followed for four years. Higher intake of dietary fiber, potassium and magnesium were each significantly associated with lower risk of hypertension. Even those who did not develop diagnosable hypertension still had a greater rise in blood pressure with time if they consumed lower amounts of these dietary substances.12

The diet that best maximizes fiber, potassium and magnesium is a plant-based diet. Such a diet emphasizes vegetables, fruits, whole grains, legumes, seeds and nuts. Good examples come from the traditional foods of Asia, the Mideast, Latin America and Africa. All revolve around a core of legumes and grains such as lentils and rice, beans and corn, or soy and millet--topped with local vegetables and fruits. A good general guideline is to select ethnic foods.

Exercise: Epidemiological reviews have shown that exercise lowers many cardiovascular risks, including cholesterol, weight and blood pressure.13 A study of nearly 15,000 Harvard male alumni revealed that regular physical exercise was closely linked with a decreased risk of hypertension. Compared to those who routinely engaged in vigorous sports, sedentary men had a 35 percent greater risk of hypertension.14 Although aerobic exercise has been better studied, any physical activity can help lower high blood pressure.

Stress management: In one study, 132 healthy men and women were put under various stresses. Blood pressures typically went up, depending on the level and type of stress.15

People can take advantage of a variety of methods for controlling stress. Simple techniques include scheduling adequate time to complete tasks and letting go of unnecessary projects. Other methods, such as biofeedback and meditation, require a modest amount of training. A recent study of 111 African-American people with high blood pressure found that a meditative technique lowered blood pressure on par with antihypertensive drugs.16

Supplements: In addition to following healthy lifestyles, patients can also incorporate dietary supplements specific for helping control blood pressure. Taking the proper dosage is important. It's also wise to work in partnership with a qualified health practitioner. Patients should not abruptly discontinue antihypertensive medications without appropriate medical guidance.

Magnesium: One of the better studied antihypertensive supplements is magnesium--a mineral important to numerous enzymes and cell membrane permeability to sodium and calcium. Studies show that supplemental magnesium helps relax the smooth muscle of blood vessels. Most likely, it modulates vessel contractibility that's caused by such naturally occurring chemicals as bradykinin, angiotensin II, serotonin, prostaglandins and catecholamines.17

A Dutch study of 91 elderly patients with mild to moderate hypertension found that, compared to placebo, magnesium aspartate significantly reduced blood pressure.18 In a Swedish study, 20 hypertensive patients were given magnesium aspartate supplements for six months. Magnesium levels inside their cells rose, and both systolic and diastolic pressures fell significantly. In addition, the treatment group had increased cellular levels of potassium, which helps control blood pressure.19

Potassium: Recent studies show the value of supplemental potassium in managing blood pressure.20 Increasing dietary potassium can also offset the tendency of excess dietary sodium chloride (salt) to raise blood pressure. A low to normal potassium intake encourages this salt-induced blood pressure rise.21

The American diet typically does not provide adequate potassium, but potassium needs are easily satisfied by a varied, whole-foods diet. Sodium needs, on the other hand, are less than 1,000 mg daily. In the United States and many other industrialized countries, the ratio of sodium to potassium intake is typically reversed. Given our current knowledge, people should maximize potassium through diet and supplements and reduce their sodium intakes.

Calcium: This mineral is another supplement associated with blood pressure regulation. Results of clinical trials on calcium supplementation, however, have been mixed. One study suggests that calcium may even contribute to hypertension, possibly because it competes with magnesium.22 Although the combined effect of calcium and magnesium on blood pressure hasn't yet been determined, magnesium appears more important.

Coenzyme Q10: An antioxidant and an essential component of energy metabolism, Co-Q10 plays a significant role in treating hypertension and heart failure. A study of 109 heart failure patients who also had hypertension demonstrated a clear benefit for those taking Co-Q10. At an average of 4.4 months, 51 percent of the patients were able to discontinue their hypertension medications. Those with heart failure improved significantly.23

An Italian study of 26 patients treated for 10 weeks with 100 mg daily of Co-Q10 revealed a significant reduction in blood pressure and improved cholesterol profiles. Average systolic blood pressures decreased from 164 to 146, and diastolic blood pressures decreased from 98 to 86. Average total cholesterol decreased from 223 mg/dl to 213 mg/dl and HDL cholesterol (the "good" cholesterol) increased from 41 mg/dl to 43 mg/dl.24

Garlic (Allium sativum): Studies are confirming the wisdom of garlic's traditional use as a treatment for hypertension. A recent pilot study of nine patients receiving high dosages (2,400 mg daily) of a deodorized garlic preparation showed a significant decline of both systolic and diastolic pressures.25 Although the results were positive, this study was not randomized or placebo-controlled.

Another study suggested a possible explanation for garlic's effect on blood pressure. The endothelial cells, which line the arteries, produce a relaxing factor known as nitric oxide. When these cells are damaged they may produce less nitric oxide, leading to blood vessel spasm and higher blood pressure. In vitro, garlic preparations increase the activity of nitric oxide synthase, the essential enzyme for production of nitric oxide.26

Taurine: This amino acid is another nutrient supplement that may help control blood pressure. A study of hypertensive rats showed that taurine supplementation not only normalized the increased nervous system activity often associated with high blood pressure, but also elicited a beta-endorphin (a natural opiate) response that relaxed the blood vessels.27 These findings suggest that taurine may help to reduce blood pressure. Other studies show that taurine helps relieve congestive heart failure by enhancing the contractile ability of heart muscle.28

Other Supplements: Herbs such as hawthorn (Crataegus oxyacantha) and essential fatty acids (e.g., gamma-linolenic acid and omega-3 fatty acids) may also help control blood pressure.

In general, it's best to use supplements in the context of a comprehensive health-care approach--one that includes healthy diet, exercise and stress management. Potential benefits go beyond controlling blood pressure to improving overall well-being.

Michael Janson, M.D., is president of the American Preventive Medical Association and a fellow and president-elect of the American College for Advancement in Medicine. Janson is the author of The Vitamin Revolution in Health Care (Arcadia Press, 1996). He practices nutrition therapy, chelation therapy and preventive medicine at the Center for Preventive Medicine in Barnstable, Mass.

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