Those who drank the most of both beverages – four or more cups of green tea plus at least two cups of coffee – lowered their risk of dying from any cause by 63 percent. Chief researcher Dr Yuji Komorita, from Kyushu University in Japan: “We demonstrated that greater consumption of green tea and coffee was significantly associated with reduced all-cause mortality. The effects may be additive.”
Previous research has suggested the drinks could be beneficial for health because of the various bioactive compounds they contain. But few of these studies were carried out on diabetics.
In this study, researchers tracked the health of almost 5,000 Japanese people with type 2 diabetes, with an average age of 66, for five years.
Dr Komorita said: “Compared with those who drank neither beverage, those who drank one or both had lower odds of dying from any cause, with the lowest odds associated with drinking higher quantities of both green tea and coffee.”
Drinking up to one cup of green tea each day was associated with 15 percent lower odds of death, while drinking two to three cups was associated with a 27 percent lower risk.
Getting through four or more cups was linked to 40 percent lower odds.
Among coffee drinkers, one cup a day was associated with 19 percent lower odds.Two or more cups lowered the risk by 41 percent.
The chance of dying early was even lower for those who drank both green tea and coffee every day.
Type 2 diabetes can cause problems with the eyes, heart and nerves and is often linked to being overweight or inactive, or having a family history of the condition. Dr Komorita said of the new research: “The biology behind these observations isn’t fully understood.
“Green tea contains several antioxidant and anti-inflammatory compounds, including phenols and theanine, as well as caffeine.
“Coffee also contains numerous bioactive components, including phenols. As well as its potentially harmful effects on the circulatory system, caffeine is thought to alter insulin production and sensitivity.”
The findings are being published in the online journal BMJ Open Diabetes Research and Care today.