Low sodium/high potassium diet for prevention of hypertension: probable mechanisms of action.
20 normotensive subjects (10 with a family history of hypertension) were investigated as to whether moderate salt restriction and/or a high potassium intake had a beneficial effect on blood pressure regulation and prevention of hypertension. In all subjects a moderate reduction of salt intake from 200 to 50 mmol/day over 2 weeks reduced the rise in blood pressure induced by various doses of noradrenaline (0.1, 0.2, and 0.4 microgram/kg/min). Furthermore, of 20 subjects 12 (8 with a family history of hypertension) responded to salt restriction with a fall in systolic or diastolic blood pressure of at least 5 mm Hg. There were no significant differences in plasma renin, aldosterone, vasopressin, and catecholamine levels between responders (salt-sensitive subjects) and non-responders, but salt-sensitive subjects had a mean baseline diastolic blood pressure which was higher than that of salt-insensitive subjects by 13 mm Hg (77.3+/-3.26 vs. 64.6+/-2.06, p less than 0.001). A high potassium intake reduced diastolic blood pressure by at least 5 mm Hg in 10 out of 20 subjects, of the 10 7 had a family history of hypertension and 9 responded to salt restriction. A high potassium intake also improved compliance with a low salt regimen, promoted sodium loss, prevented the rise in plasma catecholamines induced by a low salt diet, and increased the sensitivity of the baroreceptor reflex. These four effects occurred in the group as a whole and were probably the means by which a high potassium intake reduced blood pressure. In all subjects 2 weeks of a combined low sodium/high potassium intake reduced blood pressure rises induced by mental stress or noradrenaline infusion by 10 mm Hg. The results of this study suggest that moderate salt restriction combined with a high potassium intake helps to prevent hypertension, that salt-sensitive subjects exist, and that these individuals would profit most.
D000328:Adult; D001794:Blood Pressure / Q000187:drug effects; D001835:Body Weight; D003401:Creatine / Q000652:urine; D004039:Diet, Sodium-Restricted; D006801:Humans; D006973:Hypertension / Q000178:diet therapy / Q000517:prevention & control*; D008297:Male; D010349:Patient Compliance; D011188:Potassium / Q000008:administration & dosage* / Q000494:pharmacology; D011674:Pulse / Q000187:drug effects; D011897:Random Allocation; D014527:Uric Acid / Q000652:urine
D014527:Uric Acid; D003401:Creatine; D011188:Potassium