Effects of Habitual Coffee Consumption on Cardiometabolic Disease, Cardiovascular Health, and All-Cause Mortality

James H. O'Keefe, MD; Salman K. Bhatti, MD; Harshal R. Patil, MD; James J. DiNicolantonio, PHARMD; Sean C. Lucan, MD, MPH, MS; Carl J. Lavie, MD


J Am Coll Cardiol. 2013;62(12):1043-1051. 

In This Article

Coffee and Insulin Sensitivity

Antioxidants in coffee, such as chlorogenic acid, have been recognized to improve glucose metabolism and insulin sensitivity.[11] A recently published randomized study found that consumption of 5 cups of coffee per day increased adiponectin levels and decreased insulin resistance.[12] Caffeine acutely activates 5'-adenosine monophosphate–activated protein kinase and insulin-independent glucose transport in skeletal muscle.[13] Studies in rat models confirmed that it upregulates insulin-like growth factor 1 signaling, which in turn enhances insulin sensitivity as well as insulin secretion.[14]

A systematic review of 9 cohort studies compared minimal to low coffee consumption (<2 cups/day) with that of heavy coffee consumption (≥6 cups/day) for the risk of the development of type 2 diabetes mellitus (T2DM). These researchers concluded that the risk of the development of T2DM was lowest in subjects who drank >6 cups daily (relative risk [RR]: 0.65; 95% CI: 0.54 to 0.78) and also was significantly reduced for subjects who consumed 4 to 6 cups daily (RR: 0.72; 95% CI: 0.62 to 0.83) (Fig. 1).[15] A prospective study of >88,000 women 26 to 46 years of age established a linear relationship of coffee consumption with the reduction in T2DM, whereby even small amounts of coffee on a daily basis conferred benefit.[16] Associations were similar for noncaffeinated and caffeinated coffee.

Figure 1.

The Relationship Between Coffee Consumption and Subsequent Type 2 Diabetes Mellitus in Different Categories of Coffee Consumption
The center of each black square is placed at the summary point estimate; the area of the square is proportional to the population size; and each vertical line shows the 95% confidence interval about the summary estimate. Reprinted with permission from Husley et al.15