Zinc intake and plasma zinc level are maintained in men consuming cholesterol-lowering diets

Abstract

Objective: Reduced zinc intake has been reported when cholesterol-lowering diets are adopted. This study examined whether such diets compromise the zinc status of men with hypercholesterolemia.

Design: Zinc intake on baseline 4-day food records and baseline plasma zinc levels were compared with intake and levels 12 and 24 months after subjects adopted a low-fat, increased-fiber diet. Dietary fiber intake, supplement use, alcohol intake, and exercise were evaluated as possible confounding variables.

Subjects: Subjects were free-living men (n = 365) with baseline cholesterol level above the 75th percentile who were participants in a randomized trial comparing cholesterol-lowering diets with goals of 30%, 26%, 22%, and 18% of energy from fat and 300, 200, 100, and 100 mg cholesterol, respectively.

Statistical analyses: Data were analyzed using two sample t tests, multiple linear regression, and analysis of variance.

Results: For all subjects combined, mean fat and cholesterol intakes approached or met the guidelines of the National Cholesterol Education Program step 2 diet, with approximately 30 g fiber per day. Density (mg/1,000 kcal) of zinc intake was unchanged from the baseline value. We found a slightly positive relationship between fiber and zinc intakes; no relationship between fiber intake and plasma zinc level; no effect of supplement use (category included all types of supplements), alcohol use, or level of exercise on plasma zinc levels; and no difference by dietary assignment in zinc intake or plasma zinc levels.

Application: Zinc status does not appear to be at risk in adult men who adopt cholesterol-lowering diets. These results may not be generalized to higher-risk population groups or situations in which dietary counseling is less comprehensive.