This article is more than 5 years old. Information may no longer be current.
One more daily cup of coffee may reduce risk for type 2 diabetes
Upping the intake of caffeinated coffee by one cup each day for 4 years can reduce the risk for diabetes, according to findings from a study at Harvard School of Public Health published in Diabetologia.
Researchers analyzed observational data on consumption of caffeinated and decaffeinated coffee and caffeinated tea from three prospective studies: 48,464 women aged 30 to 55 years in the Brigham and Women’s Hospital-based Nurses’ Health Study (1986-2006); 47,510 women aged 25 to 42 years in Nurses’ Health Study II (1991-2007); and 27,759 men aged 40 to 75 years in the Health Professionals Follow-up Study (1986-2006). Participants responded to questionnaires at baseline and every 2 years thereafter to update their information on diet, lifestyle, medical conditions and other chronic diseases.
For this investigation, Frank Hu, MD, PhD, and Shilpa Bhupathiraju, a research fellow, both of the department of nutrition at the Harvard School of Public Health, and colleagues evaluated participants’ diet every 4 years through food-frequency questionnaires, with self-reported type 2 diabetes validated by additional surveys. Researchers documented 7,269 cases of type 2 diabetes.
Participants who increased their coffee intake by more than one cup/day (median change, 1.69 cups per day) for 4 years had an 11% (95% CI, 3-18) lower risk for type 2 diabetes in the subsequent 4 years compared with those who made no changes. “High-stable consumers” (≥3 cups per day) had a 37% lower risk for type 2 diabetes than “low-stable consumers” (≤1 cup per day). No changes in risk were observed for changes in decaffeinated coffee consumption.
Results showed participants who decreased their coffee intake by more than 1 cup/day (median change, 2 fewer cups/day) were at a 17% (95% CI, 8-26) higher risk for type 2 diabetes. No association was found between changes in tea consumption with type 2 diabetes risk.
Disclosure: This study was funded by research grants from the NIH. One of the researchers received a postdoctoral fellowship grant from the American Heart Association. Another researcher received funding from Nestec, a broad food company that also sells coffee, for an unrelated trial on the effects of coffee consumption on insulin sensitivity.
Collapse