Salt Substitutes Could Reduce Hypertension in Older Adults

Yangfeng Wu, MD, PhD

Credit: Peking University Clinical Research Institute

A new study found switching from regular salt to salt substitutes can reduce hypertension—or high blood pressure—in older adults.¹ People who used a salt substitute had a 40% lower incidence and likelihood of developping hypertension than people who consume regular salt.²

Watching sodium levels is important for older adults with hypertension as it can reduce blood pressure and keep them healthy. Hypertension is considered the leading risk factor for cardiovascular disease and mortality, affecting > 1.4 billion adults and causing 10.8 million deaths per year worldwide.

“Adults frequently fall into the trap of consuming excess salt through easily accessible and budget-friendly processed foods,” said lead investigator Yangfeng Wu, MD, PhD, executive director of Peking University Clinical Research Institute in Beijing, China. “It’s crucial to recognize the impact of our dietary choices on heart health and increase the public’s awareness of lower-sodium options."

Prior studies found reducing salt consumption can prevent or delay new-onset hypertension. However, data is scarce and controversial, making it difficult to determine the outcomes of long-term salt reduction.¹

Since an effective way to reduce hypertension risk is to reduce sodium intake, a study evaluated salt substitutes (62.5% NaCI, 25% KCI, and 12.5% flavorings) as a new alternative to salt to maintain a healthy blood pressure rather than reducing salt in their diet. Investigators evaluated the incidence of hypertension and hypotension in older adults with normal blood pressure.

The study included 611 participants from 48 care facilities who were > 55 years old (mean age: 71.4 years). Participants were split evenly into 2 groups: one group replaced regular salt with a salt substitute (n = 313) and the second group continued using regular salt (n = 298).

At baseline, participants had a blood pressure of < 140/ 90 mmHg and were not using anti-hypertension medications. At the follow-up, the team looked for participants who had incident hypertension, started anti-hypertension medications, or developed major cardiovascular adverse events.

Two years in, participants with salt substitutes were 40% less likely to develop hypertension than participants with regular salt. The incidence of hypertension was 11.7 per 100 people-years in participants with a salt substitute and 24.3 per 100 people-years in participants with regular salt (adjusted hazard ratio [aHR, 0.60; 95% CI, 0.39 to 0.92; P = .02). Participants with salt substitutes did not have an increase incidence of hypotension episodes compared to participants with regular salt (9.0 vs. 9.7 per 100 person-years; P = .76), so their blood pressure levels remained at a healthy level.

Furthermore, mean systolic or diastolic blood pressure did not increase by the end of the study in the salt substitute group (mean changes: −0.3 ± 11.9/0.2 ± 7.1 mm Hg) but increased in the regular salt group (7.0 ± 14.3/2.1 ± 7.5 mm Hg). With both groups, investigators observed a net reduction of – 8.0 mm Hg (95% CI, -12.4 to -3.7 mmHg) in systolic and -2.0 mm Hg (95% CI, -4.1 to 0.1 mm Hg) in diastolic blood pressure.

“Our results showcase an exciting breakthrough in maintaining blood pressure that offers a way for people to safeguard their health and minimize the potential for cardiovascular risks, all while being able to enjoy the perks of adding delicious flavor to their favorite meals,” Wu said.² “Considering its blood pressure–lowering effect, proven in previous studies, the salt substitute shows beneficial to all people, either hypertensive or normotensive, thus a desirable population strategy for prevention and control of hypertension and cardiovascular disease.”

A limitation the investigators pointed out was that the study was a post-hoc analysis, which impacted study outcomes as they were not prespecified, and many patients did not have follow-up visits, which contributed to a lack of data.

“In Chinese older adults with normal blood pressure, replacing usual salt with a salt substitute may reduce the incidence of hypertension without increasing hypotension episodes,” investigators concluded.¹ “This suggests a desirable strategy for population-wide prevention and control of hypertension and cardiovascular disease, deserving further consideration in future studies.”

^References

1. ^{Zhang, X, Yuan Y, Li, C. Effect of a Salt Substitute on Incidence of Hypertension and Hypotension Among Normotensive Adults. Journal of the American College of Cardiology. 2024; 83 (7) 711-722. https://www.jacc.org/doi/full/10.1016/j.jacc.2023.12.013}
2. ^{Salt Substitutes Help to Maintain Healthy Blood Pressure in Older Adults. EurekAlert! February 12, 2024. https://www.eurekalert.org/news-releases/1033923. Accessed February 14, 2024.}