Effects of Dietary Potassium on WNK1, Blood Pressure, and Insulin Metabolism
The study design is a double blinded crossover study with 2 phases. The non-african american and african american subjects will constitute two separate groups. each group will be randomized to receive the high or low potassium intake first. each phase is 4 weeks in duration, and the phases will be separated by a 21day wash out period during which subjects will be counseled to consume random diets. at the end of the washout week, they will crossover to the opposite phase of the study. The study will be double blinded with respect to the study medications. Potassium Supplementation: all subjects will be maintained on a low potassium diet, 30 meq/day, during both phases. Potassium supplementation in the form of potassium chloride (KCl) will be provided to achieve high K+ intake. Placebo tablets will be provided during the low K+ phase. The placebo tablets will appear similar to KCl and will be indistinguishable by both participants and investigators. Two 10meq tablets will be taken with breakfast, two with lunch and three with dinner daily to achieve 70 meq K+ supplementation during the high K+ intake phase.
Healthy volunteer subjects, 21 years of age and greater, either gender, with a BMI greater than 18.5 kg/m2 will be included. There will be no children, institutionalized mentally disabled, or prisoners enrolled in this study. Spanish speaking subjects will be included in this study.