Beta-Carotene Environmental Factors May Influence Study Results
This article was originally published in The Tan Sheet
Executive Summary
Future studies of chemopreventive agents such as beta-carotene should take into account the variations between the nutrient's natural and synthetic forms as well as environmental factors, several researchers state in the June 21 issue of the Journal of the National Cancer Institute.
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Beta carotene
Women randomly assigned to receive 50 mg of the antioxidant on alternate days showed "no statistically significant differences in incidence of cancer, cardiovascular disease or total mortality after a median of 4.1 years," Women's Health Study researchers report in the December Journal of the National Cancer Institute. Over a median treatment duration of 2.1 years, 19,939 women received beta carotene and an equal number were given placebo; follow-up lasted for two years. The study recorded 378 cancers in the beta carotene group compared to 369 among controls, 42 instances of MI compared to 50 for controls and 61 cases of stroke compared to 43 for controls. The results mirror those from other studies, including the Carotene & Retinol Efficacy Trial and the Alpha-Tocopherol, Beta Carotene Cancer Prevention study