Why was this study done?
Beta-carotene has many health benefits and is a safe method to increase both beta-carotene and vitamin A status. High doses of beta-carotene, though, have been reported to change the coloring of the skin. This study was designed to investigate higher dosing of beta-carotene (30,000 IU, 60,000 IU, 90,000 IU) along with a high beta-carotene diet (for an additional 25,000 – 30,000 IU a day) and its effects on skin color.
What did the study find?
After twelve weeks, no skin changes were seen in the first group (total of around 60,000 IU/day – from diet and supplementation). Seven out of nine participants in the middle group (90,000 IU total a day), and all of the highest group (120,000 IU total) had skin changes. None of the participants in the study had altered blood chemistry during the study.
Effects of Graded Levels of Beta-Carotene on Skin Yellowing in Healthy Humans.
Authors: Jensen, C.D., A. Dronkert, and J. Whittam. FASEB J, 1989. 3(3): p. A465.
PDF Abstract: FASEB J, 1989.