Gauging Salt Sensitivity

Are you sensitive to salt? It will take a doctor to tell you for sure, but you can get a pretty good idea on your own, experts say.

The most specific test requires an experienced specialist, says Dr. Myron Weinberger of the Indiana University School of Medicine.

One technique involves bringing the patient to a research center, giving him or her an intravenous load of salt solution for four hours, then measuring blood pressure. The next day, most of the salt is removed from the system with a low-salt diet and a powerful diuretic before blood pressure is measured again.

Another approach is to give the patient a diet high in salt for four or five days, then a low-salt diet for seven days. Although physicians have specific criteria for defining high sensitivity, a 5 mm Hg change in either the systolic or diastolic components of blood pressure would suggest salt sensitivity, Weinberger says.

Alternatively, says Dr. Harriet Dustan of the University of Vermont, you can get an informal assessment of your sensitivity with a blood-pressure cuff and a food table that provides sodium values. Total your sodium and measure your blood pressure for a week to get an average value. Then cut back on your sodium for a few days and see what happens.

If your blood pressure drops only one or two points, you are probably not sensitive, she says.