Salt substitutes are effective in reducing stroke, major cardiovascular events

A salt substitute that includes less sodium reduced rates of stroke and heart attack in rural China, according to a trial published in the New England Journal of Medicine.

These salt substitutes are a promising intervention in areas where most salt intake comes from home cooking, according to Darwin Labarthe, MD, PhD, MPH, professor of Preventive Medicine in the Division of Epidemiology and a co-author of the study.

In Northeastern China, or other parts of the world where manufactured foods are still a small part of the food supply, this is an intervention that’s practical. Hundreds of millions of people could benefit."

Darwin Labarthe, MD, PhD, MPH, Professor of Preventive Medicine, Division of Epidemiology, Northwestern University

Reducing salt intake reduces blood pressure, which is a primary contributor to disease and death from heart attack or stroke. As many as one billion people around the world have uncontrolled high blood pressure, Labarthe said, and that number only continues to grow.

Salt substitutes — in this study, a salt made of a mix of sodium chloride and potassium chloride — have been shown to reduce blood pressure, but their impact on downstream cardiac events had previously not been determined.

In the current study, conducted in 600 villages in Northeastern China, investigators recruited more than 20,000 individuals with a history of high blood pressure or stroke. Study villages were randomized either to receive the salt substitute or to continue using regular salt in home cooking.

Investigators followed participants for an average of nearly five years, finding that rates of stroke, major cardiovascular events and death were all lower in participants using salt substitutes when compared to participants using regular salt.

The results strongly suggest that salt substitutes — especially those that replace sodium with potassium — are an effective, practical and low-cost cardiovascular disease intervention in areas of the world where home cooking is prevalent, according to Labarthe.

"Salt is being decreased and potassium is being increased, which is also beneficial in lowering blood pressure — so it's doubly effective," Labarthe said.

However, for more developed countries — especially in the West — public health must turn to food manufacturers, according to Labarthe.

"The evidence suggests that if food manufactures used salt substitutes in processed foods, that could have a substantial health benefit," Labarthe said. "Cardiovascular disease is itself a major pandemic, one that's been with us for a century, and salt substitutes could have a huge impact."

The study was led by investigators from The George Institute for Global Health in Sydney, Australia.