Summary: Drinking 4 or extra cups of black, inexperienced, or oolong tea every day was related to a 17% decrease danger of growing Type 2 diabetes.
A scientific evaluation and meta-analysis of 19 cohort research involving greater than 1 million adults from eight international locations finds that reasonable consumption of black, inexperienced or Oolong tea is linked to a decrease danger of growing kind 2 diabetes.
The findings, being introduced at this yr’s European Association for the Study of Diabetes (EASD) Annual Meeting in Stockholm, Sweden (19-23 Sept), counsel that consuming not less than 4 cups of tea a day is related to a 17% decrease danger of T2D over a mean interval of 10 years.
“Our results are exciting because they suggest that people can do something as simple as drinking four cups of tea a day to potentially lessen their risk of developing type 2 diabetes”, says lead creator Xiaying Li from Wuhan University of Science and Technology in China.
While it’s lengthy been recognized that often consuming tea could also be helpful for well being as a result of of the numerous antioxidant, anti-inflammatory and anticarcinogenic compounds tea incorporates, much less clear has been the relationship between tea consuming and the danger of T2D. So far, revealed cohort research and meta-analyses have reported inconsistent findings.
To deal with this uncertainty, researchers carried out a cohort examine and a dose-response meta-analysis to raised outline the relationship between tea consumption and future T2DM danger.
First, they studied 5,199 adults (2583 males, 2616 girls) with no historical past of T2D (common age 42) from the China Health and Nutrition Survey (CHNS), who had been recruited in 1997 and adopted till 2009. The CHNS is a multicentre potential examine taking a look at the economics, sociological points and well being of residents from 9 provinces.
At the outset, members stuffed in a foods and drinks frequency questionnaire and offered data on life-style components corresponding to common train, smoking and alcohol consumption. Overall, 2,379 (46%) members reported consuming tea, and by the finish of the examine, 522 (10%) members had developed T2D.
After adjusting for components which might be recognized to be linked with elevated danger of T2D, like age, intercourse, and bodily inactivity, researchers discovered that tea drinkers had an identical danger of growing T2D in comparison with non-drinkers. And the outcomes didn’t change considerably when analysed by age and intercourse, or when members who developed diabetes throughout the first 3 years of follow-up had been excluded.
In the subsequent step of the examine, the researchers did a scientific evaluation of all cohort research investigating tea consuming and the danger of T2D in adults (aged 18 or older) as much as September 2021. Overall, 19 cohort research involving 1,076,311 members from eight international locations  had been included in the dose-response meta-analysis.
They explored the potential impression of differing kinds of tea (inexperienced tea, oolong tea, and black tea), frequency of tea consuming (lower than 1 cup/day, 1-3 cups/day, and 4 or extra cups/day), intercourse (female and male), and the location of the examine (Europe and America, or Asia), on the danger of T2D.
Overall, the meta-analysis discovered a linear affiliation between tea consuming and T2D danger, with every cup of tea consumed per day decreasing the danger of growing T2D by round 1%.
When in contrast with adults who didn’t drink tea, those that drank 1-3 cups every day lowered their danger of T2D by 4%, whereas those that consumed not less than 4 cups on daily basis decreased their danger by 17%.
The associations had been noticed regardless of the kind of tea members drank, whether or not they had been male or feminine, or the place they lived, suggesting that it could be the quantity of tea consumed, fairly than another issue, that performs a serious function.
“While more research needs to be done to determine the exact dosage and mechanisms behind these observations, our findings suggest that drinking tea is beneficial in reducing the risk of type 2 diabetes, but only at high doses (at least 4 cups a day)”, says Li.
She provides, “It is possible that particular components in tea, such as polyphenols, may reduce blood glucose levels, but a sufficient amount of these bioactive compounds may be needed to be effective. It may also explain why we did not find an association between tea drinking and type 2 diabetes in our cohort study, because we did not look at higher tea consumption.”
Oolong tea is a standard Chinese tea that’s produced from the identical plant used to make inexperienced and black teas. The distinction is how the tea is processed—inexperienced tea just isn’t allowed to oxidise a lot, black tea is allowed to oxidise till it turns black, and oolong tea is partially oxidised.
Despite the essential findings, the authors be aware that the examine is observational and can’t show that consuming tea decreased the danger of T2D, however means that it’s prone to contribute.
And the researchers level to a number of caveats, together with that they relied on subjective assessments of the portions of tea consumed they usually can not rule out the chance that residual confounding by different life-style and physiological components could have affected the outcomes.
About this diabetes analysis information
Author: Judy Naylor
Contact: Judy Naylor – Diabetologia
Image: The picture is in the public area
Original Research: The findings shall be introduced at The European Association for the Study of Diabetes Annual Meeting