Green Tea Does Not Prevent Recurrent Adenomas in Females, but It Might in Males

Green Tea Does Not Prevent Recurrent Adenomas in Females, but It Might in Males

Douglas K. Rex, MD, MASGE, reviewing Seufferlein T, et al. Am J Gastroenterol 2022 Feb 25.

Green tea contains catechins, which have anticancer properties and reduce the incidence of polyps in mouse models with a mutation in the Adenomatous polyposis coli gene. 

In a randomized controlled trial of patients with adenomas at colonoscopy, patients received capsules containing catechins or placebo and had follow-up colonoscopy at 3 years.

The overall incidence of adenomas with placebo was 55.7% versus 51.1% with green tea (P=.16). In the per-protocol analysis, adenomas were found in 54.3% of patients given the placebo versus 48.3% given green tea extract (P=.12). 

In a prespecified analysis, there was no difference between the effects of placebo and green tea on adenomas in females; however, the incidence in males was 60.4% with placebo versus 52.9% with green tea (P=.048). There was no impact on advanced adenomas in either gender.

Douglas K. Rex, MD, FASGE


Overall, this is a negative study, but the results leave the question open regarding the effect of green tea on reducing the incidence of adenomas in males. Since green tea is harmless overall, it could be added to the list of potential measures offered to the many patients who ask about steps they can take to reduce recurrent adenomas, or at least it might be offered to male patients. More study is needed.

Note to readers: At the time we reviewed this paper, its publisher noted that it was not in final form and that subsequent changes might be made.


Seufferlein T, Ettrich TJ, Menzler S, et al. Green tea extract to prevent colorectal adenomas, results of a randomized, placebo-controlled clinical trial. Am J Gastroenterol 2022 Feb 25. (Epub ahead of print) (

Nach oben scrollen