LOW FAT, NOT LOW-SALT DIET, LOWERS BLOOD PRESSURE
Report #7095; 4/15/97
A recent article in the New England Journal of Medicine (1) supports many other studies (2,3) showing that a diet rich in fruits and vegetables and low in fat helps to lower high blood pressure significantly. Other studies show that a diet low in salt is ineffective in reducing high blood pressure for most people (4).
Many people think that low-salt diets lower high blood pressure because they know that salt holds water. Increasing salt intake expands blood volume and therefore, should raise blood pressure. However, the data shows that low-salt diets are relatively ineffective in lowering high blood pressure because reducing salt intake a little does not lower high blood pressure and reducing salt intake a lot can raise blood pressure even higher. Severe salt restriction is not safe. People on low-salt diets have a much higher death rate (5), and high blood pressure medications may lower intelligence and I.Q points later in life (6). furthermore, severe salt restriction can raise blood pressure (7) and blood cholesterol (8),/ and even cause a heart attack (9). Salt deficiency causes your kidneys and adrenal glands to produce large amounts of the hormones, renin and aldosterone, which raise blood pressure (10).
On the other hand, low-fat diets, exercise, weight reduction and alcohol restriction lower high blood pressure, and adding blood pressure medicines to this regimen lowers high blood pressure even more (1)Most doctors will recommend salt restriction.
By Gabe Mirkin, M.D., for CBS Radio News
1) Appel LJ et al. A clinical trial of the effects of dietary patterns on blood pressire. NEJM 1997 (April 17); 336: 1117-1124.
2) Hypertension 1991; 18 (suppl 1): 115-120.
3) American Journal of Hypertension 8: 11 (NOV 1995): 1067-1071.
4) JAMA May 21, 1996.
5) Hypertension 25: 6 (JUN 1995): 1144-1152.
6) JAMA December 20, 1995.
7) Klin Wochenschrift 1990; 68: 664-668.
8) Klin Wochenschrift 1991 69 suppl: 51-57.
9) American Journal of Hypertension 7: 10 Part 1: OCT 1994: 886-893.
10) JAMA May 28, 1996: 1590-1597.
Health Reports from The Dr. Gabe Mirkin Show and DrMirkin.com