The mechanism by which alcohol consumption affects psoriasis has not been fully clarified. Most researchers suggest that alcohol affects psoriasis mainly by adversely affecting the immune system, and thus predisposing drinkers to infections ([199-201], but see [202]). It has also been suggested that the stimulatory effect of ethanol and acetone (which exceeds its normal endogenous level in the blood of heavy drinkers) on keratinocytes, causing epidermal hyperproliferation, may be one of the reasons why psoriasis can be precipitated by alcohol use in genetically predisposed individuals [199-201]. In sum, consistent with [202], we conclude that there is a consistent association between alcohol consumption and psoriasis, but that the overall level of evidence for causality is insufficient, especially with respect to biological pathways.
