Potassium-Rich Foods May Offset Heart Risk of High Sodium, Researchers Say

By Ryan Flinn - Jul 12, 2011 4:00 AM GMT+0800

Foods rich in potassium such as blueberries and sweet potatoes may help offset heart risks associated with high-salt diets, a study suggests.

The research, which examined the diets of more than 12,000 people over an average of 15 years, found higher death rates from heart disease in those who had elevated sodium to potassium ratios. The report from the U.S. Centers for Disease Control and Prevention was published today in the Archives of Internal Medicine.

Public health authorities in most developed countries recommend reducing salt intake by roughly half. Still, studies that looked at sodium levels alone in relationship to heart disease have shown mixed results, with some finding no evidence that a low-salt diet reduces death rate or cuts cardiovascular complications. Today’s study found a higher correlation between the ratio of sodium to potassium and heart disease and death than just looking at salt or potassium alone.

“The association between sodium and cardiovascular disease is not straight forward and remains an area of controversy today,” said Elena Kuklina, one of the study’s authors and an epidemiologist at the Atlanta-based CDC, in an interview.

The results may be due to the nutrients offsetting each other, Kuklina said.

High levels of sodium can stiffen endothelial cells, thicken and narrow resistance arteries and block nitric oxide synthesis, while high potassium levels can spur nitric oxide release, counteracting the effects of sodium.

“Reduced sodium intake accompanied by increased potassium intake could achieve greater health benefits than restricting sodium alone,” the study said.

Processed Food Ratios

Processed foods, such as cheese, cooked meats and fast food tend to have a higher sodium-to-potassium ratio, whereas fruits, dairy products and vegetables tend to have a lower ratio, according to the study.

“If you just try to stick to unprocessed food, you would have low sodium and high potassium intake,” Kuklina said.

The findings are from the CDC’s National Health and Nutrition Examination Survey, a program that uses surveys and physical examinations to assess the health and nutrition status of Americans.