Article

Diabetologia

, Volume 57, Issue 7, pp 1346-1354

Changes in coffee intake and subsequent risk of type 2 diabetes: three large cohorts of US men and women

  • Shilpa N. BhupathirajuAffiliated withDepartment of Nutrition, Harvard School of Public Health
  • , An PanAffiliated withSaw Swee Hock School of Public Health and Yong Loo Lin School of Medicine, National University of Singapore and National University Health System
  • , JoAnn E. MansonAffiliated withDivision of Preventive Medicine, Brigham and Women’s Hospital and Harvard Medical SchoolDepartment of Epidemiology, Harvard School of Public Health
  • , Walter C. WillettAffiliated withDepartment of Nutrition, Harvard School of Public HealthDepartment of Epidemiology, Harvard School of Public HealthChanning Division of Network Medicine, Brigham and Women’s Hospital and Harvard Medical School
  • , Rob M. van DamAffiliated withSaw Swee Hock School of Public Health and Yong Loo Lin School of Medicine, National University of Singapore and National University Health System
  • , Frank B. HuAffiliated withDepartment of Nutrition, Harvard School of Public HealthDepartment of Epidemiology, Harvard School of Public HealthChanning Division of Network Medicine, Brigham and Women’s Hospital and Harvard Medical School Email author 

Abstract

Aims/hypothesis

Coffee and tea consumption has been associated with a lower type 2 diabetes risk but little is known about how changes in coffee and tea consumption influence subsequent type 2 diabetes risk. We examined the associations between 4 year changes in coffee and tea consumption and risk of type 2 diabetes in the subsequent 4 years.

Methods

We prospectively followed 48,464 women in the Nurses’ Health Study (NHS; 1986–2006), 47,510 women in NHS II (1991–2007) and 27,759 men in the Health Professionals Follow-up Study (HPFS; 1986–2006). Diet was assessed every 4 years using a validated food-frequency questionnaire. Self-reported cases of incident type 2 diabetes were validated by supplementary questionnaires.

Results

During 1,663,319 person-years of follow-up, we documented 7,269 cases of incident type 2 diabetes. Participants who increased their coffee consumption by more than 1 cup/day (median change = 1.69 cups/day) over a 4 year period had an 11% (95% CI 3%, 18%) lower risk of type 2 diabetes in the subsequent 4 years compared with those who made no changes in consumption. Participants who decreased their coffee intake by more than 1 cup/day (median change = −2 cups/day) had a 17% (95% CI 8%, 26%) higher risk for type 2 diabetes. Changes in tea consumption were not associated with type 2 diabetes risk.

Conclusions/interpretation

Our data provide novel evidence that increasing coffee consumption over a 4 year period is associated with a lower risk of type 2 diabetes, while decreasing coffee consumption is associated with a higher risk of type 2 diabetes in subsequent years.

Keywords

Caffeinated coffee Change Coffee Decaffeinated coffee Tea Type 2 diabetes