Drinking more coffee — both regular and decaffeinated — and tea appears to lower the risk of developing Type 2 diabetes, according to new research published in the Archives of Internal Medicine. Should the protective effects of these beverages prove to be real, the implications could be substantial for the roughly 380 million people worldwide expected to have Type 2 diabetes by 2025.
Using a type of research known as meta-analysis (in which statistics from several studies are combined and examined), researchers looked at data from 18 studies, with a total of 457,922 participants, that analyzed the association between coffee consumption and diabetes risk. Six of these studies also looked at decaffeinated coffee, while seven studies analyzed the association between tea consumption and diabetes risk.
When the results of the studies were combined, it was found that each additional cup of coffee consumed in a day was associated with a 7% reduction in the excess risk of diabetes. Drinking three to four cups of caffeinated coffee per day was associated with a 25% lower risk of diabetes than drinking two cups or less per day; consuming three to four cups of decaffeinated coffee daily was associated with an approximately 33% lower risk. Similarly those who drank three to four cups of tea per day were found to have a roughly 20% lower risk of diabetes than those who did not drink any tea.
Because of the apparent reduction in diabetes risk associated with decaffeinated coffee, the protective effects of this beverage appear to extend beyond just caffeine content. The study authors theorized that other substances in coffee and tea, such as magnesium and antioxidants, might also be involved.
Nonetheless, Lars Rydén, spokesman for the European Society of Cardiology, notes that while drinking coffee may be protective, it is not the most important step for warding off diabetes: “Coffee helps, but other things are even more important. Those who are overweight should reduce their body weight by 5–10% — not too much — and include physical activity such as a brisk walk for 30 minutes a day. Then those people who are at risk of developing diabetes will reduce this risk by 40–50%.”
To learn more, read the article “Drinking Coffee, Decaf and Tea Regularly Associated With a Reduced Risk of Diabetes” or see the study’s abstract in the Archives of Internal Medicine.