FRIDAY, March 23 (HealthDay News) -- Although earlier studies
had linked coffee to an increased risk for psoriasis, a large new
study finds no such evidence.
Psoriasis is a common skin condition that causes skin redness
and irritation. Most people with psoriasis have areas of thick, red
skin with flaky, silver-white patches called scales.
"Our hypothesis was whether caffeine would lower the risk of psoriasis because there are hypotheses in the past that caffeine might be an anti-inflammatory," said lead author Dr. Abrar Qureshi, an assistant professor of dermatology at Harvard Medical School in Boston.
"However, we found there was no association between coffee intake and the risk of psoriasis," he said.
These findings agree with other studies that found no
association between coffee and this skin condition, the researchers
noted.
The reason that there has been an association of psoriasis with
coffee may have to do with smoking and alcohol, which are known
risk factors for psoriasis, Qureshi said. In the study, those who
drank the most coffee also drank the most alcohol and smoked, he
said.
"There have been reports that coffee increases the risk of psoriasis and that coffee helps quell psoriasis," he said. However, this study found no risk or benefit from coffee, Qureshi added.
The report was published in the March issue of the
Archives of Dermatology.
For the study, Qureshi's team collected data on almost 83,000
women who took part in the Nurses' Health Study. In this large
population, the researchers found no link between coffee or
caffeine and developing psoriasis.
Dr. Doris Day, a dermatologist at Lenox Hill Hospital in New
York City, said that this finding "makes perfect sense; it's what I
would have suspected."
The real risk factor may be smoking, she said. "Smoking is toxic
to every organ system and is especially toxic to the skin."
However, Day said that caffeine can be soothing to the skin and
it is an ingredient in many skincare products, but it is not used
for psoriasis, she said.
More information
For more about psoriasis, visit the
National
Psoriasis Foundation.