Drinking 12 or more cups of coffee daily was associated with a significant reduction in the incidence of type 2 diabetes over nearly 8 years, compared with consuming no coffee, according a study.
The study looked at the self-reported coffee intake of the 4,579-person Strong Heart Study, an investigation of cardiovascular disease in 13 American Indian tribes/communities. Participants in that study had baseline data collected during 1989–1992 and were followed for an average of 7.6 years.
Participants in the current analysis were the 1,141 men and women who had normal fasting glucose at baseline, wrote Dr. Ying Zhang of the Oklahoma University Health Sciences Center, Oklahoma City, and associates (Nutr. Metab. Cardiovasc. Dis. 2009; Feb. 18 2010 [doi:10.1016/j.numecd.2009.10.020]).
The 92 (8.1%) participants who reported drinking at least 12 cups of coffee daily had a 67% lower risk (hazard ratio, 0.33) of developing type 2 diabetes during the follow-up period than did non–coffee drinkers, even after adjustment for age, gender, smoking, alcohol use, family history of diabetes, physical activity, and body mass index, the researchers noted.
In fact, coffee consumption was significantly related to diabetes risk only in those people who drank 12 or more cups daily.
The findings support those from several other studies showing a link between caffeine intake and diabetes development, but this is one of the few investigations that focused on a population known to have a high incidence of diabetes and on a group that, at baseline, had normal glucose tolerance.
The study was limited by a lack of available dietary data on the participants. It is plausible that high coffee consumption is a marker for dietary patterns and factors related to diabetes risk but not measured in this study, Dr. Zhang and associates noted.
The study was supported by grants from the National Heart, Lung, and Blood Institute, Bethesda, Md.
A dozen cups of coffee or more per day yielded significant risk reduction.
Source ©Robert Brown/Fotolia.com