Table 3—

Risk of type 2 diabetes by combinations of total coffee consumption and caffeine intake

Quintiles of caffeine intake
Q1–Q2Q3Q4–Q5
Total coffee less than one cup per day
    Median coffee consumption (cups/day)000
    Median caffeine intake (mg/day)52173287
    Number of cases/person-years533/292,658184/79,18342/18,638
    RR (95% CI)1 (ref.)1.02 (0.86–1.21)0.85 (0.62–1.16)
Total coffee 1.0–1.9 cups/day
    Median coffee consumption (cups/day)1.11.11.6
    Median caffeine intake (mg/day)74186297
    Number of cases/person-years38/31,55087/68,14274/40,348
    RR (95% CI)0.89 (0.63–1.23)0.88 (0.70–1.10)0.90 (0.70–1.16)
Total coffee two or more cups per day
    Median coffee consumption (cups/day)2.52.52.6
    Median caffeine intake (mg/day)51189430
    Number of cases/person-years18/22,97920/25,533267/287,087
    RR (95% CI)0.52 (0.32–0.83)0.50 (0.32–0.79)0.59 (0.50–0.69)
  • RRs were multivariate adjusted as described in the legend of Table 2.