A potassium-enriched salt substitute could help prevent nearly three million deaths and more than 10 million new cases of heart and kidney disease worldwide each year, a study in Nature Health suggests.
Researchers at the George Institute for Global Health in Australia used data on diet and disease risk from 4.6 billion adults in 193 countries to estimate what might happen if people switched from regular salt. Their findings came from computer modeling, not a clinical trial, and the estimates may not be exact, the researchers noted.
About 1.4 billion adults have high blood pressure, a major risk factor for stroke, heart attack and chronic kidney damage, according to the World Health Organization. Too much sodium can make the body retain water, raising blood volume and putting more pressure on artery walls.
Potassium-enriched salt replaces some of the sodium in regular salt with potassium. It can be used in much the same way, while lowering sodium intake and increasing potassium, which helps blood vessels relax and the body get rid of sodium.
If people switched only the salt they use at home, the model estimated that about 1.85 million deaths and 6.19 million new cases of heart and kidney disease could be avoided each year. Replacing salt in restaurant meals and processed foods alone was projected to prevent around 1.56 million deaths and 5.46 million new cases annually.
The researchers also modeled a more focused approach: encouraging 80% of adults diagnosed with high blood pressure to use potassium-enriched salt at home. That scenario was linked to an estimated 590,000 fewer deaths each year.
Potential gains differed from one region to another, in part because of population size and where people get most of their sodium. China had the largest estimated benefit, with about 1.08 million deaths potentially prevented annually if salt were fully replaced. The estimate was nearly 400,000 in India and roughly 105,000 in the United States, along with 492,000 fewer new disease cases.
In many Asian and African countries, much of the salt people consume comes from home cooking. The researchers said better access to alternatives and greater public awareness could help make the switch. In Western countries, where more than 70% of dietary sodium comes from processed foods and restaurant meals, wider use by food makers and restaurants would likely be needed.
Dr. Nathan Goodyear of the Williams Cancer Institute in California, who was not involved in the research, said the findings point to how small changes may affect heart and kidney disease. He added that health is shaped over time by the environments and habits people build, often well before a disease is diagnosed.
The models indicated that, for the population overall, the potential heart-health benefits outweighed the risks. Still, potassium-enriched salt is not suitable for everyone. It can contribute to hyperkalemia, when too much potassium builds up in the blood and may cause dangerous changes in heart rhythm, the National Kidney Foundation warns.
Most people get rid of excess potassium through urine. But those with advanced kidney disease, or people taking certain blood pressure medicines, may not be able to clear it effectively. The World Health Organization advises people with conditions that interfere with potassium removal to avoid these substitutes unless a healthcare professional recommends them.
Goodyear cautioned against expecting a single solution to prevent or treat chronic illness. Heart and kidney disease, diabetes and cancer can develop over time through a combination of factors.
Cost may also be a barrier: potassium-enriched salt is about twice as expensive as regular salt on average, the researchers said. Wider adoption would also depend on cooperation from food manufacturers and suppliers.
