Research

Mixed

Long-term consumption of coffee (regular or decaffeinated) and total caffeine is associated with a statistically significant reduction in the risk of developing type 2 diabetes mellitus.

If you currently drink coffee, continuing or moderately increasing your intake (up to 6+ cups/day) is associated with a significantly lower risk of developing type 2 diabetes. This benefit applies to both regular and decaffeinated coffee, suggesting factors beyond caffeine (like magnesium and antioxidants) contribute. However, do not start drinking coffee if you do not currently consume it solely for diabetes prevention; the observational nature of the evidence means causality is not proven, and individual tolerance to caffeine varies.

GoodSupportsHIGH confidence
These data suggest that long-term coffee consumption is associated with a statistically significantly lower risk for type 2 diabetes.
Eduardo Salazar-Martı́nez et al. · Annals of Internal Medicine · 2004

Why this rating

Large prospective cohort studies (HPFS and NHS) with long follow-up and rigorous adjustment for confounders, but observational design prevents causal proof.

Source

Coffee Consumption and Risk for Type 2 Diabetes Mellitus

Eduardo Salazar-Martı́nez et al. · Annals of Internal Medicine · 2004

DOI 10.7326/0003-4819-140-1-200401060-00005

cohort · n=126210Cited 463×
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DOI resolved against Crossref · corpus check 2026-06-10

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