Serum beta-carotene before and after beta-carotene supplementation

Eur J Clin Nutr. 1992 Jan;46(1):15-24.

Abstract

A two-month double-blind, placebo-controlled supplementation study of oral beta-carotene (20 mg daily) was conducted. Two hundred and twenty two 30-69 year old men were randomized into either a beta-carotene or placebo group, and serum samples were obtained at baseline, follow-up (2 months), and up to 12 weeks post-supplementation. Serum beta-carotene increased on average 10-fold in the beta-carotene group, from 0.53 +/- 0.32 mumol/l (mean +/- SD) at baseline to 4.99 +/- 2.47 mumol/l at follow-up (P less than 0.0001), and beta-carotene levels remained elevated up to 12 weeks post-supplementation (0.61 +/- 0.15 mumol/l). No changes in serum retinol, alpha-tocopherol, or total cholesterol were observed. At baseline, serum beta-carotene levels were positively correlated with dietary beta-carotene (r = 0.29) and inversely correlated with body mass index and serum gamma-glutamyltransferase (r = -0.33 and r = -0.40, respectively). The inverse association with body mass index and serum gamma-glutamyltransferase persisted during active supplementation, whereas the positive association with dietary beta-carotene disappeared. In multivariate analysis, serum cholesterol was also positively associated with serum beta-carotene levels both before and after supplementation. Baseline serum beta-carotene was the factor most strongly associated (positively) with serum beta-carotene after supplementation. Our study highlights the importance of several factors which affect serum beta-carotene.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Administration, Oral
  • Adult
  • Aged
  • Body Mass Index
  • Carotenoids / administration & dosage
  • Carotenoids / blood*
  • Cholesterol / blood
  • Double-Blind Method
  • Humans
  • Male
  • Middle Aged
  • Vitamin A / blood
  • Vitamin E / blood
  • beta Carotene
  • gamma-Glutamyltransferase / blood

Substances

  • beta Carotene
  • Vitamin A
  • Vitamin E
  • Carotenoids
  • Cholesterol
  • gamma-Glutamyltransferase