In a very large cohort of African-American women in the US, the association between the consumption of alcohol, tea, and coffee and the development of type 2 diabetes mellitus (late onset diabetes) was studied for 12 years. Tea and decaffeinated coffee showed no relation with diabetes, but the regular moderate intake of both caffeinated coffee and alcohol appeared to reduce the risk of contracting late onset diabetes significantly.
This paper is particularly important because some previous studies have not shown a strong association between alcohol and the risk of cardiovascular disease among African-Americans. African-Americans, especially women, tend to drink little alcohol, yet are at markedly increased risk of late onset diabetes. In the present study, the approximately 30% lower risk for moderate alcohol drinkers was about the same in these African-American women as has been found in many previous studies of Caucasians.
Detailed critique of this paper by the International Scientific Forum on Alcohol Research.