High blood pressure, or hypertension, affects more than 1.4 billion people worldwide, and causes almost 11 million deaths per year. Reducing one's salt intake is one of the most effective ways to lower hypertension risk. Most people find it hard to reduce the amount of salt, sodium chloride, in their diets. Not only have they developed a taste for salty foods, salt is in most of the processed foods they buy. Using a potassium-based salt substitute may be a better way to control blood pressure than reducing salt consumption alone, a study by Chinese researchers has found.

“Considering its blood pressure-lowering effect, proven in previous studies, the use of a salt substitute may benefit all people, even if they do not have hypertension,” Yangfeng Wu, lead author of the study, said in a statement. Wu, executive director of the Peking University Clinical Institute, went on to say the use of salt substitutes may be an effective way to prevent and control hypertension and cardiovascular disease at the population level.

At the end of the two-year follow-up period, those who used salt substitute were 40 percent less likely to develop hypertension than those using regular salt.

Data from 611 participants enrolled in the DECIDE-Salt study were included in the current analysis. All participants were residents at elder care facilities in China, and about 74 percent were men. Participants had blood pressure less than 140/90 mm Hg at baseline, and were not taking medication to treat hypertension. The average age of participants was about 71 years old.

About half of participants, 313 people, replaced salt with a potassium-enriched salt substitute, while the remaining 298 participants continued using regular salt.

At the end of the two-year follow-up period, those who used salt substitute were 40 percent less likely to develop hypertension than those using regular salt. The salt substitute also did not cause low blood pressure, or hypotension, a common issue in older adults.

The salt substitute group did not see an increase in average systolic and diastolic blood pressure during the follow-up, but blood pressure measurements did increase in the regular salt group. Those who used the salt substitute had a systolic blood pressure about 8 mm Hg lower and a diastolic blood pressure about 2 mm Hg lower than those in the regular salt group.

“…[S]alt substitutes should be adopted early in the food chain by the food industry, so that the sodium-potassium ratio of processed foods will improve.”

The salt substitute was given to the kitchen staff at the eldercare facilities; and to keep salty processed food to a minimum, the kitchens were not allowed to provide externally-sourced food more than once per week. “This approach potentially has a greater impact on blood pressure outcomes, and for this reason, salt substitutes should be adopted early in the food chain by the food industry, so that the sodium-potassium ratio of processed foods will improve,” Rik Olde Engberink, a researcher at Amsterdam University Medical Center, wrote in a related editorial.

Salt intake is very high in China while potassium intake is low, so these results may not be applicable to other populations with different diets, the researchers write. They also point out that since most of the participants were men, it is not yet clear whether their findings are applicable to women.

The study and related editorial are published in the Journal of the American College of Cardiology.