Light to moderate drinkers with a lower risk of type 2 diabetes
A new study from Harvard University showed that compared to non-drinking, light to moderate consumption of alcoholic beverages was associated with a lower risk of type 2 diabetes among men and women. These results were driven by drinking frequency.
Excessive consumption of alcoholic beverages is associated with various adverse health outcomes, however, the association between light to moderate drinking (≤ 30 g of alcohol/day) and risk of type 2 diabetes (T2D) remains controversial. The World Cancer Research Fund and the Dietary Guidelines for Americans both recommend limiting alcohol consumption and advise against initiating drinking for any reason. On the other hand, many epidemiological studies have observed a lower risk of type 2 diabetes with light to moderate drinking (≤ 2 drinks or 30 g of alcohol/day and ≤ 1 drink or 15 g of alcohol/day for women).
Thus, the evidence regarding moderate consumption of alcoholic beverages and T2D has been inconsistent between observational studies and Mendelian randomization studies. The current study investigated how the total intake of alcoholic beverages and drinking pattern (frequency vs. quantity, beverage type, drinking with meals) was associated with T2D risk.
The researchers used data from 3 prospective study populations (Nurses’ Health Study and Health Professional Study) with former drinkers excluded and who have been followed up for 3 decades. Among the over 200,000 participants, 20,551 T2D cases were documented.
The results showed a significantly lower risk of T2D among moderate drinkers (both men and women) compared with non-drinkers. The lower risk of T2D among drinkers was largely driven by frequency instead of quantity consumed. The inverse association was apparent in women at 1-2 drinking days per week and in men, at 3-4 days/week and was strongest for more than 5 days per week, regardless of drinking < 10 g or ≥ 30 g alcohol per drinking day. A 20-30% lower T2D risk was observed comparing ≥ 5 drinking days with 1-2 drinking days/week. Drinking with meals had inconsistent but possibly modest inverse associations with T2D. Moderate red and white wine consumption was related to a reduced risk of T2D.
The authors conclude that this was the first study to examine the joint pattern of alcohol drinking frequency and quantity with T2D among women. They found that light to moderate consumption of alcoholic beverages may contribute to a lower risk of T2D but they do not recommend to initiate drinking for T2D prevention.
