A new study seems to show that non-light beer may boost risk of psoriasis in women. But yet others say that it is vitamin D deficiency that could be the culprit, beer having only an incidental role to play.
Psoriasis is a chronic, autoimmune disease that occurs on the skin when the immune system send out wrong signals that speed up the growth of skin cells.
The study led by Abrar A. Qureshi, M.D., M.P.H., of Brigham and Women's Hospital and Harvard Medical School, Boston found women who drank five or more non-light beers per week were 2.3 times as likely as those who did not drink beer to be diagnosed with psoriasis.
The authors of the study said in their report that alcoholic beverages have been suspected for a long time as a risk factor for psoriasis onset and psoriasis worsening. Alcohol drinkers are known to be more likely to suffer the disease and alcohol may exacerbate the severity of the disease.
For the study, the researchers surveyed 82,860 women aged 27 to 44 who participated in the NUrses' Health Study II for the amount and type pf alcohol they consumed through biennial questionnaires and participants reported also whether they were diagnosed with psoriasis.
Women who had an average of 2.3 drinks or more each week were 72 percent more likely than those who did not drink alcohol to report they suffered psoriasis, the study found.
Women who drank five or more non-light beers per week were found to have 1.8 times higher risk for the disease compared to those who did not drink non-light beers.
If only confirmed cases of psoriasis were considered, the risk for the condition was 2.3 times higher for those who drank five or more non-light beers per week compared to those who did not drink beer.
Light beer, wine and liqueurs on the other hand were not linked to increased risk for psoriasis.
The researchers suggested that malted barley, the main ingredient used in non-light beer, may be the culprit for the elevated risk of psoriasis.
Barley, they said, contains gluten, to which some people with psoriasis show a sensitivity. Light beers contain lower amounts of barley while non-light or dark beers contain higher amounts of this ingredient.
The authors suggested that women at a high risk of psoriasis may consider not drinking non-light beer.
The findings have been published in in the December 2010 issue of Archives of Dermatology.
However, it has also been suggested that there could be another angle to the story. People tend to drink more dark beers in the winter when vitamin D deficiency is more commonly found than in the summer.
Vitamin D has been known to be involved in the immune system, and deficiency of this sunshine vitamin can cause a wide spectrum of diseases including autoimmune diseases, according to the Vitamin D Council. So it is possible that vitamin D deficiency is linked to increased risk of psoriasis.
In fact, vitamin D products are used to ease symptoms of psoriasis.
According to a study reported in the Aug 2009 issue of Journal of Drugs in Dermatology, calcitriol ointments can be used to improve symptoms of psoriasis. The efficacy may be boosted by ultraviolet B phototherapy.
Calcitriol is the naturally occurring active form of vitamin D3. Ultraviolet B can induce the vitamin when the skin is exposed to the UV ray.
In another report, the author whose name remains unknown in the pubmed database, says the U.S. Food and Drug Administration has actually approved one such ointment to treat psoriasis.
Because many factors may influence the risk of psoriasis, it remains unknown whether avoiding non-light beer would help reduce the risk.