Wednesday, August 9, 2017
Alcohol and skin cancer: When the devil is ignoring the details
Summer has me thinking about skin cancer (I am a plastic surgeon after all) and recent reports that drinking alcohol increases the risk of skin cancer are not helping to ease my mind. "Drinking just one glass of beer or wine a day could give you skin cancer, scientists have warned," reports Britain’s Mail Online. Researchers reached this conclusion by analyzing pooled results from previous studies (the notorious meta-analysis; see last month’s post.) It seems that every drink increases your odds of developing non-melanoma skin cancer by around 10 percent. But just as blending random wines together may produce something drinkable but lacking nuance, pooling results of different types of studies may obscure crucial details. With the specific question of wine consumption and skin cancer risk, the details are especially important.
Granted, some of the studies are very well done and should not be dismissed out of hand. These results were widely characterized as applying to all types of drinking. But here’s the first important detail: only white wine and liquor consumption were associated with basal cell skin cancer (BCC), the most prevalent type. BCC being strongly associated with UV exposure from sunlight, it is possible that white wine and cocktail drinkers simply spent more time outdoors. It is also possible that red wine has completely different effects.Results from the Nurses Health Study, involving nearly 168,000 women whose health and lifestyle were tracked for decades, align with findings from the more than 43,000 men in the Health Professionals Follow-Up Study: when analyzed for non-melanoma skin cancer: alcohol consumption had a clear correlation.[i]
But not all studies conclude that alcohol is associated with skin cancer. In fact most do not; a review from the UK’s University of Nottingham looked at 22 publications on lifestyle and skin cancer risk, and found no relationship to drinking of any type.[ii]
There’s actually good evidence for red wine having a protective effect against skin cancer. A very large study from Australia – where skin cancer is particularly prevalent – looked at diet and lifestyle factors associated with pre-cancerous lesions known as Actinic Keratoses.[iii] The lowest rate of AK’s was in the group that drank the most wine, specifically red. Other studies point to a reason for this, according to another Australian report.[iv] Consumption of foods rich in polyphenol antioxidants – wine, tea, fruits and vegetables – confers protection against UV damage to the skin. This was documented in an interesting study from Germany, in which they found that consumption of red wine diminished redness of the skin from standardized doses of UV light.[v] (This is the same method used to test sunscreens, which measures the time to produce redness, known as the Minimal Erythema Dose or MED.) Interestingly, this group also studied topical application of red wine, finding minimal benefit; you have to drink it.
So slather on the sunscreen, have a glass of (red) wine and enjoy the sunshine.
[i] Wu S, Li WQ, Qureshi AA, Cho E. Alcohol consumption and risk of cutaneous basal cell carcinoma in women and men: 3 prospective cohort studies. Am J Clin Nutr. 2015 Nov;102(5):1158-66.
[ii] Leonardi-Bee J, Ellison T, Bath-Hextall F. Lifestyle factors of smoking, BMI and alcohol on the risk of Non-Melanoma Skin Cancer in adults: a systematic review. JBI Libr Syst Rev. 2012;10(6):352-398.
[iii] Hughes MC, Williams GM, Fourtanier A, Green AC. Food intake, dietary patterns, and actinic keratoses of the skin: a longitudinal study. Am J Clin Nutr. 2009 Apr;89(4):1246-55.
[iv] Chen AC, Damian DL, Halliday GM. Oral and systemic photoprotection. Photodermatol Photoimmunol Photomed. 2014 Apr-Jun;30(2-3):102-11.
[v] Moehrle M, Dietrich H, Patz CD, Häfner HM. Sun protection by red wine? J Dtsch Dermatol Ges. 2009 Jan;7(1):29-32, 29-33.