Medinews e-Newsletter - July 2009 - A service from the IJCP Group of Publications

High-Salt Diet Dampens Effects of Blood Pressure Drugs

Dr KK Aggarwal

Two studies have shown that not only does a high-salt diet contribute to hypertension, but it can also reduce the effectiveness of blood pressure medications. High blood pressure is a major risk factor for heart attack, stroke and other cardiovascular problems, and heavy salt intake has long been known to contribute to the condition.

First study published in Hypertension evaluated 12 people with resistant hypertension, high blood pressure that can't be controlled by a three-drug regimen. In the trial, half were assigned to a low-salt diet containing half tea spoon of salt a day. The other half had a high-salt diet, containing 2.5 teaspoons daily. Those on the low-salt diet had an average drop of 22.7 points in systolic blood pressure (upper BP reading) and 9.1 points in diastolic or lower blood pressure reading.

Second study reported in the same issue of the journal described a significant reduction in high blood pressure from a modest reduction in salt intake in a group that included whites, blacks and Asians. That study, done at St. George's University of London in England, had 169 participants, all of whom had moderately high blood pressure. After reducing their salt intake from 9.7 grams a day to 6.5 grams a day, the average reduction in a six-week period was 4.8 points in systolic upper pressure and 2.2 points in diastolic lower pressure.