Research

Mixed

Consuming two or more cups of coffee per day is associated with a substantially lower risk of type 2 diabetes in younger and middle-aged women, an effect observed for both caffeinated and decaffeinated coffee.

If you are a woman between 26 and 46 years old, drinking 2-3 cups of coffee daily (caffeinated or decaf) is linked to a significantly lower risk of developing type 2 diabetes. You don't need to drink excessive amounts to see this benefit. If you are sensitive to caffeine or have sleep issues, choose decaffeinated coffee. Avoid adding large amounts of sugar or high-calorie creamers, as these can lead to weight gain, which increases diabetes risk. Focus on the coffee itself as a healthy habit.

GoodSupportsHIGH confidence
consumption of two or more cups of coffee per day was associated with a substantially lower risk of type 2 diabetes during 10 years of follow-up. This association was similar for caffeinated and decaffeinated coffee and for filtered and instant coffee.
Rob M. van Dam et al. · Diabetes Care · 2006

Why this rating

Large prospective cohort study (N=88,259) with long follow-up and rigorous adjustment for confounders, though observational design prevents causal proof.

Source

Coffee, Caffeine, and Risk of Type 2 Diabetes

Rob M. van Dam et al. · Diabetes Care · 2006

DOI 10.2337/diacare.29.02.06.dc05-1512

cohort · n=88259Cited 274×
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DOI resolved against Crossref · corpus check 2026-06-10

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