DASH stands for the Dietary Approaches to Stop Hypertension. The DASH diet is based on DASH Study results published in 1997. The study showed that a diet rich in fruits, vegetables and low fat dairy foods, with reduced saturated and total fat could substantially lower blood pressure. It is the diet recommended by the National Heart, Lung and Blood Institute (part of the National Institute of Health) for lowering blood pressure.
Dash is rich in potassium and calcium, two nutrients that cause natriuresis (diuretic), but the effects on salt excretion seem much greater than either of those two. This suggests that a combination of factors is involved in the blood pressure effects.
Some people with mildly elevated blood pressure may be able to reduce blood pressure with the diet alone. For patients who require blood pressure-lowering medication, the DASH diet would probably enhance the effects of the medication, much as diuretics do when added to other blood pressure medication.
Since diuretics can cause side effects, the DASH diet offers a safer alternative to diuretic drugs.
I found a solid prove from a patient's dietary analysis
The other day, a patient of mine presented her 3-day dietary analysis with nutritional software. one is before dash, the other is with the dash. The nutrients that missing most before she stars the dash is potassium, rich in green leafy, may play a significant role in her dropping blood pressure.