from WHO-ISH 1999 Guidelines

Complex dietary changes
Vegetarians have lower blood pressure than meat eaters and vegetarian dietary patterns can lower blood pressure in hypertensive patients. A series of controlled dietary trials indicate that these effects depend on a combination of effects of fruit, vegetables, fibre and low saturated fat intake rather than the presence or absence of meat protein. This conclusion has been confirmed in a recent study in which older subjects with mild or borderline hypertension were randomised for eight week periods to continue their normal diet, to increase fruit and vegetable consumption alone, or to also reduce their consumption of total and saturated fat. Increasing fruit and vegetable consumption alone caused SBP/ABP to fall by 3/1 mmHg while the added measure of reducing fat intake led to a fall of 6/3 mmHg. In the patients with higher initial blood pressures, there was a fall of 11/6 mmHg with the combined dietary regime. The presence of higher intakes of calcium, magnesium or potassium may have contributed to the beneficial effects of some of these diets. Regular fish consumption as part of a weight reducing diet may enhance blood pressure reduction in obese hypertensive patients and yield additional benefits on lipid profiles. Hypertensive patients should be advised to eat more fruit and vegetables, to eat more fish and to reduce their fat intake.