Salt plus potassium is an equation to ponder

The salt content of your diet is important -- we’ve heard that from health experts over and over again. But a new study suggests that it’s the relationship between salt and potassium that matters, not just how much salt you consume.

The study, published Monday in the Archives of Internal Medicine, examined survey results from 12,267 Americans. The participants completed one or two 24-hour diet-recall surveys and then were followed for more than 14 years. The researchers, from the Centers for Disease Control and Prevention, found that a high sodium intake was linked to a higher likelihood of death from any cause during the study period while a higher potassium intake was associated with a lower risk of death during the study. People who had a higher sodium-to-potassium ratio had a higher risk of cardiovascular disease and death from ischemic heart disease.

While the study confirms the potential dangers of consuming too much salt, it’s less clear what to do about potassium in the diet. People who consume a largely plant-based diet naturally get less sodium and more potassium. But few Americans follow such a diet. Instead high-salt, low-potassium levels are often found in popular processed foods and snacks, say the authors of an editorial accompanying the study.

It’s difficult to add potassium to foods because some people can be harmed by too much potassium. And it’s unclear whether potassium supplements would have the same impact as potassium in natural sources.

“It is crucial that we understand the interplay of sodium and potassium in the diet and how to optimize intake in an increasingly processed food supply without generating harm,” said Dr. Lynn D. Silver and Dr. Thomas A. Farley, of the New York City Department of Health and Mental Hygiene, in their editorial.

Doctors should continue to urge people to cut back on salt and eat more foods with potassium, such as vegetables. Moreover, they said, manufacturers should be required to display potassium content on food labels so that consumers can shop carefully.

“From a public health point of view, reduced sodium intake accompanied by increased potassium intake could achieve greater health benefits than restricting sodium alone,” wrote the authors of the study.

Foods high in potassium include: broccoli, peas, lima beans, tomatoes, potatoes (especially their skins), sweet potatoes, winter squashes, citrus fruits, cantaloupe, bananas, kiwi, prunes, apricots, milk and yogurt.

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