While sun exposure is well known as a common trigger for rosacea flare-ups, there may be even more reason for rosacea sufferers to protect themselves from the sun's rays. A new study found that people with rosacea had significantly higher levels of vitamin D in their blood than people who did not have the disorder.

Vitamin D is actually a group of molecules the body produces when exposed to sunlight, and may also be ingested either in food or supplements. At healthy levels, vitamin D helps the body absorb calcium and phosphate, maintaining strong bones and regulating the immune system. Vitamin D deficiency can cause rickets, osteomalacia and osteoporosis, and has been associated with multiple sclerosis (MS).

In the new study, published in Cutaneous and Ocular Toxicology, researchers checked levels of vitamin D in the blood of 44 rosacea patients and 32 individuals without the disorder. They found those with rosacea had an average vitamin D level 25 percent higher than the healthy individuals. Although the researchers noted that larger studies are needed to confirm a clear effect, they felt these results "suggest that increased vitamin D levels may lead to the development of rosacea."

This is one of the first studies to examine vitamin D's relationship with rosacea. In a study related to NRS-funded research on cathelicidins, a type of protective molecule found in the skin, Dr. Jürgen Schauber and Dr. Richard Gallo unexpectedly discovered that vitamin D3 is involved in the regulation of cathelicidins, and may thus help create an active form of the molecules that appear to cause the bumps and pimples of rosacea.