Anti-Hypertensive Effect of a Solar Salt Diet in Elderly Hypertensive Patients: A Preliminary Randomized, Double-Blind Clinical Trial

ABSTRACT

BACKGROUND: High sodium and/or low mineral intake are known to be associated with elevated blood pressure. It has been reported that substituting low-sodium, mineral-rich salt for refined salt lowers blood pressure (BP). And solar salt is emerging as a low sodium high mineral salt for a healthy diet in Korea. Therefore, this double-blind, randomized, and placebo-controlled trial was conducted to explore changes in BP from substituting refined salt with solar salt among hypertensive elderly subjects. METHODS: Forty-three hypertensive and institutionalized elderly individuals aged 65 years or older were enrolled. Thirty-eight subjects (88.4%) completed the study. Subjects were provided with either a solar salt- or refined salt-based diet for eight weeks. RESULTS: Systolic BP decreased significantly in the solar salt-based diet group after 2, 4, and 8 weeks when compared to the refined salt-based diet group. And, diastolic BP was lowered significantly in the solar salt-based diet group compared to that in the refined salt-based diet group after 8 weeks. In addition, urinary sodium/potassium, and angiotension converting enzyme activity decreased significantly in the solar salt-based diet group compared to the refined salt-based group. Urinary potassium excretion was significantly increased in the solar salt-based diet group. CONCLUSIONS: These results may provide clinical evidence that solar salt has beneficial effects on BP in elderly patients. And, people such as Koreans, who do not consume enough minerals, may experience a greater anti-hypotensive effect by using solar salt. However, further large-scale studies are necessary.