Sun beds and cod liver oil as vitamin D sources

J Photochem Photobiol B. 2008 May 29;91(2-3):125-31. doi: 10.1016/j.jphotobiol.2008.02.007. Epub 2008 Feb 29.


The objective of this study was to (1) to determine the contribution of moderate sun bed exposure to serum 25(OH)D(3) levels; (2) to estimate the decay time of a high 25(OH)D(3) level obtained by sun bed exposure; and (3) to evaluate if the recommended ingestion of vitamin D is sufficient to maintain the 25(OH)D(3) concentration obtained by sun bed exposure. Ten volunteers (20-35 y.o.), skin type I and II, living in Olso, Norway were whole body exposed twice per week to the radiation of a commercial and approved sun bed (Life Sun S 100 W, Wolff System), starting with 0.5 MED (minimal erythema dose) and escalating to up to 1 MED per exposure for 4 weeks. After that, half of the volunteers were given a daily supplement of 200 IU vitamin D in the form of cod liver oil capsules, while the other half of the persons received no supplements. Erythema did not occur at any time and a slight pigmentation was seen in most of the volunteers after the sun bed exposures. Serum level of 25(OH)D(3) increased by about 40% on the average. The initial serum 25(OH)D(3) level was different among the volunteers (40-100 nmol/L). Within eight weeks after the last exposure the 25(OH)D(3) level decreased to the initial value in all volunteers irrespective of vitamin D supplementation or not.

Publication types

  • Controlled Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Animals
  • Body Mass Index
  • Calcifediol / blood*
  • Calcifediol / metabolism*
  • Cod Liver Oil / chemistry*
  • Dietary Supplements*
  • Female
  • Humans
  • Male
  • Seasons
  • Sunlight*
  • Time Factors
  • Vitamin D / administration & dosage*
  • Vitamin D / pharmacology*


  • Vitamin D
  • Cod Liver Oil
  • Calcifediol