- A 2009 Japanese study showed that type 2 diabetes was more prevelant among those indviduals with high stress levels, particularly men and in women with high levels of A behaviour (i.e. behaviour patterns linked to competitive drive, speed and impatience, aggressiveness and irritability). This study also observed an inverse association between coffee consumption and incidence of diabetes51
- A 2014 study suggested that coffee consumption was inversely associated with depressive symptoms amongst a group of patients with type 2 diabetes. The authors suggested this might be due to biologically active compounds in coffee in addition to caffeine52
- A 2011 US case-control study on post-menopausal women examined whether plasma levels of sex hormones and sex hormone-binding globulin (SHBG) could account for the inverse association between coffee consumption and type 2 diabetes risk, building on data that implicated the important roles of sex hormones in the development of type 2 diabetes. SHBG may directly mediate intracellular signalling of sex hormones. The study found a correlation between coffee consumption and plasma levels of SHBG. This association was not, however, found for decaffeinated coffee and tea. The authors note that these findings suggest SHBG may account for the inverse association between caffeinated coffee and type 2 diabetes risk53
