EFFECT OF A LOW BETA-CAROTENE DIET ON THE IMMUNE FUNCTIONS OF ADULT WOMEN

We examined the effect of beta-carotene depletion and repletion on the immune status of nine healthy women who lived in the metabolic suite for 100 d. For the first 4 d all women were fed a basal diet supplemented with 1.5 mg beta-carotene/d (baseline). During the next 68 d, the basal diet without beta-carotene supplementation was fed to all subjects (depletion), and during the last 28 d the diet of each woman was supplemented with 15.0 mg beta-carotene/d (repletion). Neither beta-carotene depletion nor repletion significantly (P less than or equal to 0.05) altered proliferation of peripheral blood mononuclear cells cultured with phytohemagglutinin or concanavalin A, in vitro production of soluble interleukin 2 receptor, or the concentration of circulating lymphocytes and their subsets. Thus, in healthy adults consuming adequate vitamin A, beta-carotene depletion had no adverse effect on the indexes tested, nor was there any beneficial effect of modest beta-carotene supplementation.