Date Published: 24 April 2014
Increasing daily coffee consumption may reduce risk of type 2 diabetes
A recent study by scientists based at Harvard School of Public Health (HSPH), which is located in Boston, Massachusetts (USA), suggests that drinking coffee that contains caffeine may have health benefits for some people.
The researchers found that people who increased the amount of coffee they drank each day by more than one cup over a four-year period had a 11% lower risk of type 2 diabetes than the people involved in the study who made no changes to their coffee consumption. Not only did they find that increasing consumption of coffee correspond to a lower risk of type 2 diabetes, but the researchers also found that those people who decreased their coffee consumption by more than a cup per day, increased their type 2 diabetes risk by 17%.
" Our findings confirm those of previous studies that showed that higher coffee consumption was associated with lower type 2 diabetes risk," said Shilpa Bhupathiraju, lead author and research fellow in the Department of Nutrition at Harvard School of Public Health.
" Most importantly, they provide new evidence that changes in coffee consumption habit can affect type 2 diabetes risk in a relatively short period of time."
About the data used in the study:
The researchers analyzed data about caffeinated and decaffeinated coffee, and caffeinated tea consumption from:
- 47,510 women in Nurses' Health Study II (1991-2007),
- 27,759 men in the Health Professionals Follow-up Study (1986-2006), and
- 48,464 women in the Brigham and Women's Hospital-based Nurses' Health Study (1986-2006).
Participants' diets were evaluated every four years with a questionnaire. Those people who self-reported type 2 diabetes filled out additional questionnaires. A total of 7,269 cases of type 2 diabetes were documented.
Summary of the results:
The research indicated that:
- Participants who increased their coffee* consumption by more than one cup per day (median change=1.69 cups/day) over a four-year period had a 11% lower risk of type 2 diabetes in the subsequent four years compared to those who made no changes in consumption. (A cup of coffee was defined as eight ounces, black, or with a small amount of milk and/or sugar.)
- Participants who reduced their daily coffee* consumption by more than one cup per day (median change=2 cups/day) had a 17% higher risk for diabetes.
- Changes in decaffeinated coffee consumption and caffeinated tea consumption were not associated with changes in risk for type 2 diabetes.
*standard coffee that includes caffeine.
" These findings further demonstrate that, for most people, coffee may have health benefits," said Frank Hu, senior author and professor of nutrition and epidemiology at Harvard School of Public Health (Boston, Massachusetts, USA).
" But coffee is only one of many factors that influence diabetes risk. More importantly, individuals should watch their weight and be physically active."
The results of this study are especially interesting to anyone interested in nutrition because caffeine is widely associated with adverse health consequences. For example, caffeine is often categorized as an anti-nutrient as well as a stimulant. See also caffeine included on a list of anti-nutrients.
For more on caffeine, see the effects of caffeine on the human body and caffeine withdrawal symptoms.
School of Public Health, USA