Drinking Coffee and Green Tea Reduces Mortality

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By Agata P. | Updated: Nov 16, 2023

Drinking Coffee and Green Tea Reduces Mortality
General Information
  • 03 Aug 2020
  • Japan
  • Kyushu University
  • Komorita, Y. et al
  • Epidemiological study
  • 54,923 diabetics
  • 5 years

Diabetes is a challenging disease, which is associated with reduced life expectancy.1 Besides pharmacological treatments, the focus is heavily placed on implementing lifestyle changes to improve health outcomes and prolong life.

While a good deal of research has been done on the effects of coffee and green tea on overall health, not much is known about their effects in diabetics.

In this 2020 epidemiological study, Japanese researchers explored the impact of drinking green tea and coffee on mortality in patients with type 2 diabetes.

The Study

To study potential associations, researchers analyzed data from the Fukuoka Diabetes Registry, which was a multicenter study aimed at assessing the effects of modern treatments and lifestyle practices on diabetes mellitus management.

The data pertained to 54,923 diabetes patients, aged 20 and older, who sought diabetes treatment at the local clinics. Participants were followed-up for an average of 5.3 years.

Registered information consisted of lifestyle habits, diabetes status, experienced discomforts, anthropometric measurements, and others. Coffee and green tea drinking habits were also recorded.

The Results

Out of 54,923 studied subjects, 309 died, mainly due to cancer and cardiovascular disease.

It was found that among green tea drinkers as well as coffee drinkers, all-cause mortality was significantly reduced according to the amount consumed.

Interestingly, researchers found that all-cause mortality was reduced by 63% in individuals who consumed higher amounts of both green tea and coffee.

What Does this Mean?

The results of this study suggest a strong association between higher green tea or coffee consumption and lower mortality. The effects seem to be additive in patients with type 2 diabetes who are both coffee and green tea drinkers.

While both beverages are known to contain a variety of beneficial compounds, the exact mechanism behind their effects on prolonging longevity is not well understood yet. More studies are necessary to evaluate the role of coffee and green tea in diabetes management. 

Other herbs that contribute to preventing disease and promoting long-term health are blueberries, chia, avocado, and walnuts.


  • BMJ Open Diabetes Research & Care, Additive effects of green tea and coffee on al-cause mortality in patients with type 2 diabetes mellitus: the Fukuoka Diabetes Registry, 2020


  1. Diabetes and Endocrinology. (2022). Potential Gains in Life Expectancy Associated with Achieving Treatment Goals in IS Adults with Type 2 Diabetes. Retrieved August 3, 2022 from https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2791200