In a study of nearly 2,000 elderly Taiwanese men, researchers found that those given a potassium-enriched salt substitute were 40 percent less likely to die of heart disease or stroke over the next two to three years.
The salt alternative, which was half sodium chloride, half potassium chloride, helped the men make a moderate cut in their sodium intake and a substantial increase in their potassium consumption.
This potassium boost may have been largely responsible for the lower risk of cardiovascular death, the researchers conclude in the American Journal of Clinical Nutrition.
Like sodium, potassium is an electrolyte needed for maintaining the body's fluid balance. It's also involved in proper nerve and muscle control, as well as blood pressure regulation. A number of studies have suggested that diets high in potassium -- from foods like raisins, bananas, melon, beans and potatoes -- may help maintain a healthy blood pressure.
The new findings suggest the mineral may also help lower the risk of dying from heart disease or stroke -- possibly by protecting blood vessel function, according to study co-author Dr. Wen-Harn Pan, a researcher at the Institute of Biomedical Sciences, Academia Sinica in Taipei.
While the study looked at a potassium-enriched salt, Pan told Reuters Health she suspects that a diet high in potassium-rich fruits and vegetables could be even more beneficial.
The study included 1,981 elderly men who were residents of a veterans' retirement home. Half of the men were randomly assigned to eat meals prepared with the potassium-enriched salt, while the rest had meals made with regular salt.
Over the next 30 months, the researchers found, men given the salt alternative were 40 percent less likely to die of cardiovascular disease.
The findings are in line with general nutrition advice for controlling blood pressure and lowering heart risks: eat more fresh fruits and vegetables, beans and low-fat dairy, while limiting salty processed foods.
An advantage of whole-food sources of potassium is that they contain other nutrients important to overall health, Pan noted. Still, potassium-enriched salt offers a "convenient and fast way" to alter the diet's sodium-potassium ratio, she added.
It is possible, however, for the body's potassium levels to get too high, particularly in older people who have kidney dysfunction or are taking certain medications -- including blood pressure drugs called ACE inhibitors.
Older adults should check with their doctors before using potassium-enriched salt substitutes or potassium supplements.