We are not entirely sure why this is true, but sleep apnea may be involved in some cases. Research has shown that 30 percent or more of even slightly obese hypertensive patients have sleep apnea. In at least some of these, the blood pressure improves when the sleep apnea is treated. The deleterious effect of obesity is also indirect, in that it encourages a sedentary life style, and deters active exercise which would be beneficial.

All obese patients are not alike. Some seem to have a genetic tendency to weight gain; for others obesity is a behavioral pattern. The pattern of fat distribution is a risk factor. Obese persons with fat confined to the hips and thighs (the "female" pattern) seem to be at less risk than those in whom fat is concentrated around the waist and abdomen. While this high waist to hip circumference ratio is typically a "male" pattern of fat distribution, its presence in men or women is associated with higher risk of heart disease, stroke, and death.

Weight loss requires a balance of caloric restriction and exercise tailored to the individual patient. For most, a 1200 calorie low fat, high fiber diet will result in gradual weight loss without undue discomfort. Thirty percent or less of the total calories should be as fat. The remaining calories may be distributed into three main meals and one or more snacks. Small, low calorie snacks between meals help prevent the hunger pangs which may result in overeating at the next scheduled main meal. Among overweight persons who lose weight, a very high percentage will regain their former weight within a year. Those who are more successful in consistent weight control and those who lose weight with the help of a behavioral modification program in addition to caloric control.

The role of alcohol in hypertension is complex. Besides adding calories which make weight control more difficult, it may also raise blood pressure. It is estimated that alcohol is the cause of 7 to 11 percent of hypertension in men. In large population surveys, it has been shown that those who drink 1 to 2 ounces of alcohol daily have less coronary heart disease than non drinkers. However, daily use of more than two ounces daily is associated with higher blood pressure, and more than three ounces per day is often associated with clinical hypertension. The effects of alcohol on blood pressure are more pronounced in blacks than in whites. In alcohol abusers, abstinence of alcohol use alone may be enough to lower blood pressure to safe levels. All hypertensive patients should moderate their use of alcoholic beverages.

Potassium depletion may raise blood pressure. If potassium blood levels are low, a potassium supplement may lower the pressure. In persons with normal potassium levels, however, there is no justification for potassium supplementation. A low sodium diet is likely to have a fairly high potassium content. Potassium depletion is most often seen in persons on extremely low carbohydrate diets (modified fasting), or those who are taking diuretics ("water pills"). Magnesium is a mineral which has a variable effect on blood pressure. Depletion of magnesium can also be produced by diuretics. Also, potassium deficiency may not be able to be corrected with potassium chloride supplements in the presence of magnesium deficiency.

Calcium supplements have been shown to lower blood pressure in some studies, but not in others. Some hypertensive patients, particularly older women, may not have enough calcium in their diet to protect them from osteoporosis and fractures. If supplementary calcium is taken, it should be in the form of supplementary tablets or skim milk. Increasing whole milk or cheese products for the calcium content introduces unacceptably high levels of cholesterol and saturated fats.

 Ateriosclerosis, Inevitable or Prefventable? and Hypertension, The Silent Disease,
Copyright © 1998 William H. McMicken, M.D.