Korean J Health Promot.  2015 Sep;15(3):98-107. 10.15384/kjhp.2015.15.3.98.

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

• Baek SH
• Ahn JW
• Lee HR
• Cho SH
• Kim JH

• KMID: 2247203
• DOI: http://doi.org/10.15384/kjhp.2015.15.3.98

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.

Keyword

Hypertension; Blood pressure; Aged; Salt; Randomized controlled trial

MeSH Terms

Aged*
Blood Pressure
Diet*
Humans
Hypertension
Korea
Minerals
Potassium
Sodium
Minerals
Potassium
Sodium

Figure

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  Figure 1. Flowchart of the study design and study subjects. BP, blood pressure.

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  Figure 2. (A) Changes in systolic and diastolic blood pressures with intake of solar or refined salt over eight weeks. P-values were calculated using Wilcoxon rank sum test and Wilcoxon signed rank test. (B) The rate of change in ACE activity with intake of solar (least square mean [SE]: -15.45 [16.13]) or refined salt (least square mean [SE]: 34.09 [14.82]) before and after the study. P-values were calculated using ANCOVA. ACE, angiotensin converting enzyme; SE, standard error.

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