Coffee intake and type 2 diabetes

Epidemiological studies suggests that drinking 3-4 cups of coffee per day is associated with an approximate 25% lower risk of developing type 2 diabetes, compared to consuming <2 cups per day or none^{2-4,6-8,16-28}, with an exposure response relationship^3,4,6-8

• A 2002 cohort study of 17,111 Dutch men and women suggested that coffee consumption was associated with a substantially lower risk of clinical type 2 diabetes²

• A 2009 systematic review with a meta-analysis of 457,922 individuals and 21,897 newly-diagnosed cases of type 2 diabetes from eight different countries showed a statistically significant inverse association between coffee consumption and subsequent risk of type 2 diabetes³

• A further meta-analysis published in 2018 with 1,185,210 participants and 53,018 incidents of type 2 diabetes suggested that those in the highest category of coffee consumption (±5 cups per day) had a 29% lower risk of type 2 diabetes compared vs. abstention⁴

These results are supported by additional studies and reviews, including:^14-30

• A 10 year follow-up study from Greece, published in 2015, highlighted the significance of habitual coffee drinking in relation to diabetes onset, concluding that habitual coffee drinking, at a level of at least 250 ml/day, vs. abstention, was found to exhibit significant protection against diabetes development, decreasing the risk of developing diabetes by >50%¹⁴

• A 2018 study of adults, aged 20-70 years with low levels of coffee consumption (≤1 cup of coffee per week) suggested that a lower risk of both pre-diabetes and type 2 diabetes was observed in coffee drinkers vs. abstention²⁹

• A 2021 meta-epidemiological study specifically in Asian populations, suggested that drinking one cup of coffee per day reduced the risk of type 2 diabetes by 8%³⁰