You Are What You Eat--The Effect of Health Habits on
Blood Pressure : What is the DASH Diet?
DASH stands
for Dietary Approaches to Stop Hypertension. This meal plan provides
substantial amounts of magnesium potassium and calcium—all minerals
thought to help moderate blood pressure—and, while DASH does not prohibit specific
foods, it does redirect consumers away from higher-fat and higher-sodium foods.
What the science shows:
A study of 459 subjects with and without
hypertension showed that following the DASH diet produced significant reductions in blood
pressure in both hypertensive and normotensive subjects, an effect that was apparent
within two weeks of starting the diet. Compared with those who followed a standard
American diet, those with hypertension lowered pressure by 11.4/5.5 mmHg; those without
hypertension showed an average reduction of 3.5/2.1 mmHg.1 A later analysis
showed that cutting the sodium content of the diet—originally about 3000 mg/day—to
about 1500 mg further reduced the blood pressure lowering effect.2
DASH specifics:
The meal plan includes 8-10
servings of fruits and vegetables and 2-3 serving of low-fat dairy foods.
In addition, dieters are encouraged to choose leaner protein sources like fish,
chicken, lean beef and beans over higher-fat cuts of beef and lunch meat; whole
grain breads and cereals over refined grain products, and
polyunsaturated and monounsaturated fats like vegetable oil spreads instead
of saturated fats like butter.
Adopting this meal plan will require some
retooling by some consumers—the diet includes substantially more produce than most
Americans eat and prompts adults who may not consume many dairy foods to become
reacquainted with low-fat milk, yogurt, and cheese. But the focus of this
diet is on what dieters can eat rather than on what they can’t eat—DASH doesn’t
call for special “diet” foods and doesn’t mandate a specific sodium
restriction. The addition of large amounts of produce has a dual effect—it
substitutes naturally low-sodium foods for higher-sodium choices, and adds a substantial
amount of magnesium and potassium to the diet.
Key points:
DASH includes 8-10 servings/day
of fruits and vegetables, 2-3 servings/day low fat dairy foods, is lower in fat and sodium
than the standard American diet.
DASH lowers blood pressure in
both hypertensive and normotensive subjects, so it’s a viable means of both
managing and preventing hypertension.
Further lowering the sodium content of
the diet produces additional reductions in SBP.
Resources:
The
DASH Eating Plan, National Heart, Lung, and Blood Institute
Your Guide to the DASH Diet, Oregon Dairy Council
Appel LJ, Moore TJ, Obarzanek E, et al. A clinical
trial of the effects of dietary patterns on blood pressure. N Engl J Med 1997;
336:1117.
Sacks FM, Svetkey LP, Vollmer WM, et al. Effects on
blood pressure of reduced dietary sodium and the Dietary Approaches to Stop Hypertension
(DASH) diet. N Engl J Med 2001; 344:3.
(http://www.pri-med.com)
