Sunburn can be fought with vitamin D

Washington DC: If you are experiencing pain from sunburn, you may want to reach for some vitamin D to soothe your discomfort, according to a recent study.

High doses of vitamin D taken one hour after sunburn significantly reduce skin redness, swelling, and inflammation, according to double-blinded, placebo-controlled clinical trial out of Case Western Reserve University School of Medicine and University Hospitals Cleveland Medical Center.

In the study, 20 participants were randomized to receive a placebo pill or 50,000, 100,000, or 200,000 IU of vitamin D one hour after small UV lamp "sunburn" on their inner arm. Researchers followed up with the participants 24, 48, 72 hours and 1 week after the experiment and collected skin biopsies for further testing.

Participants who consumed the highest doses of vitamin D had long-lasting benefits, including less skin inflammation 48 hours after the burn. Participants with the highest blood levels of vitamin D also had less skin redness and a jump in gene activity related to skin barrier repair.

"We found benefits from vitamin D were dose-dependent," said senior author Kurt Lu. "We hypothesize that vitamin D helps promote protective barriers in the skin by rapidly reducing inflammation. What we did not expect was that at a certain dose, vitamin D not only was capable of suppressing inflammation, it was also activating skin repair genes."

The trial is the first to describe acute anti-inflammatory benefits from taking vitamin D. According to the authors, despite widespread attention given to vitamin D deficiency, "there is a lack of evidence demonstrating that intervention with vitamin D is capable of resolving acute inflammation."

By measuring gene activity in the biopsies, the researchers also uncovered a potential mechanism behind how vitamin D aids skin repair. The results suggest vitamin D increases skin levels of an anti-inflammatory enzyme, arginase-1. The enzyme enhances tissue repair after damage and helps activate other anti-inflammatory proteins.

The study may have people flocking to vitamin supplement aisles, but Lu stresses that the trial tested very high doses of vitamin D that far exceed daily allowances.

The results are published in the Journal of Investigative Dermatology.