Salt restriction may aggravate type ii diabetes

A small study of patients with hypertension has suggested that salt restriction may result in insulin resistance, impaired glucose tolerance or a worsening of type II (non-insulin-dependent) diabetes in certain patients.

In this study, 21 hypertensive patients were given either 2 g of sodium chloride (ordinary table salt) or placebo four times a day for four weeks. The patients were then given the other treatment so that all of them received both treatments. A glucose tolerance test was performed at the end of each treatment period.

In those who received the salt, the total glycaemic response was 8 per cent lower than that seen in those who were given the placebo. This effect was most pronounced in type II diabetics, in those with salt-sensitive high blood pressure and in non-diabetics on antihypertensive drugs.

Sodium is, of course, an essential nutrient, but doctors are still a long way from finding the healthy middle ground between consuming too much and too little (Am J Hypertens, 2001; 14: 653-9).