Full-calorie beer linked to skin disease

The explanation might be the barley in the beer, said co-author Dr. Abrar A. Qureshi, assistant professor of dermatology at the Brigham and Harvard Medical School. Boston University and Harvard School of Public Health researchers also contributed to the study, which appears in the Aug. 16 online edition of the Archives of Dermatology.

Previous research has shown a link between psoriasis and sensitivity to gluten, a protein in grains such as barley and wheat. Some doctors recommend a gluten-free diet for people with the disease.

Light beer is made with less barley, which may make it less likely to trigger psoriasis, Qureshi said. Wine is made by fermenting grapes, not grain. With hard liquors that use a starch source for fermentation, such as vodka, the starches are removed from the liquor during distillation, he said.

Although the study looked at female nurses -- who tend to be healthier and drink less than the general population -- Qureshi said he expects the findings would hold true for other people as well.

"Any population of people, including men, who do drink more alcohol may be at a higher risk" for developing psoriasis, he said.

Qureshi said he and his colleagues are now taking a closer look at the nurses' diets to see whether they can find a link between psoriasis and more gluten intake.

Two other studies on psoriasis were also released today by the Archives of Dermatology. One found that patients with psoriasis had higher levels of depression and anxiety and were more likely to attempt suicide than people without the disease. The second study found that in winter, Irish patients with psoriasis were deficient in vitamin D, which the body makes when exposed to sunlight. Exposing patients to UV-B rays three times per week for a month helped clear up psoriasis outbreaks.