TAKING vitamin D pills after forgetting to use sun block cream could soothe the agony of sunburn, according to new research.

The “sunshine supplement” boosts levels of a protein in the skin that fuels tissue repair.

Scientists found high doses taken within an hour dramatically reduced redness, swelling and inflammation.

Lead author Professor Kurt Lu, of Case Western Reserve University, Ohio, said: “We hypothesise 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 activates skin repair genes.”

His team exposed 20 volunteers to a strong light resembling solar radiation to induce a sunburn on a small patch of skin on the inner arm.

They then gave them varying amounts of vitamin D - 1,250, 2,500 and 5,000 micrograms (MCG) - and followed them up one, two, three days and a week later. They also collected skin biopsies for further testing.

The nutrient, taken by millions for health reasons, had long-lasting benefits 48 hours after the burn.

It lessened soreness with the effect increasing in proportion to how it was consumed.

Taking 1,250MCG - much more than the recommended daily allowance - led to a significant reduction in redness and swelling compared to those given a placebo.

Likewise, those who took 2,500MCG had even less swelling - and those who took 5mg had the largest reduction in inflammation.

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.

The study published in the Journal of Investigative Dermatology is the first to show vitamin D can reduce inflammation in the skin.

Prof Lu, of Case Western Reserve University, Ohio, said it “could potentially help prevent sunburn.”

He said: “We found benefits from vitamin D were dose-dependent.”

Prof Lu said despite widespread attention given to vitamin D deficiency “there is a lack of evidence demonstrating 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 the nutrient increases skin levels of an anti-inflammatory enzyme, arginase-1.

This chemical enhances tissue repair after damage and helps activate other anti-inflammatory proteins.

But before people flock to vitamin supplement aisles Prof Lu stressed the trial tested very high doses of vitamin D that far exceed daily allowances.

The US Food and Drug Administration’s recommended adult daily allowance for vitamin D is just 25 MCG.

Added Prof Lu: “I would not recommend at this moment that people start taking vitamin D after sunburn based on this study alone.

“But, the results are promising and worthy of further study.”

Prof Lu and colleagues are planning additional studies that could improve treatment plans for sunburn patients.

Dermatologist Dr Barbara Gilchrest, of Massachusetts General Hospital and former editor of the journal, also advised people not to take a large dose of vitamin D.

She said: “I think that’s probably not a good idea and not well established by this study, and of course the authors aren’t saying that either.”

Although none of the participants suffered side effects large doses taken repeatedly over time can cause vitamin D toxicity, known as hypervitaminosis.

Prof Lu said it would not be easy for most healthy people to overdose on vitamin D unless they took really excessive quantities.

Research over the past few decades has found the nutrient plays many roles in the body, including helping regulate the immune system and influencing inflammation.

A small amount of exposure to UV radiation is good, because that’s how the skin naturally makes vitamin D - the main source for the substance rather than diet.

Studies have shown vitamin D tablets could help people cope with chronic backache and arthritis along with many pain-related conditions, from menstrual cramps to fibromyalgia because of its anti-inflammatory properties.

Inflammation, the body’s immune response to illness, releases proteins which make people more sensitive to pain and allow it to last for longer.