UDP-glucuronosyltransferase (UGT2B17) is the key enzyme involved in the glucuronidation of testosterone to testosterone glucuronide which is then easily eliminated from our body. Testosterone glucuronide also serves as a marker for the testosterone/epitestosterone (T/E) ratio used to detect testosterone abuse in sport.
Researchers at Kingston University in England have discovered that phenolic components, including quercetin, in red wine inhibit this enzyme that removes testosterone from the body.
Red wine could thus have a positive impact on circulating testosterone levels, thus aiding performance while potentially affecting the urinary T/E ratio and therefore masking testosterone abuse.
The team also found the results were the same for red wine extract in supplement form.
Although red wine is not a banned substance away from the sports field, Professor Naughton's team has referred its findings to the World Anti-Doping Agency because of the newly-discovered side effect of potential change to the amount of testosterone in the body.
The same researchers had earlier shown that green and white tea extracts also inhibit testosterone glucuronidation.
Previous research has also shown that non-steroidal, anti-inflammatory drugs, diclofenac and ibuprofen, can also inhibit the UGT2B17 enzyme
The above story is based on the January 7, 2013 news release by Kingston University.
The research has been Epublished ahead of print in theNutrition Journal:
Jenkinson C, Petroczi A, Naughton DP. Red wine and component flavonoids inhibit UGT2B17 in vitro. Nutr J. 2012 Sep 7; 67 DOI: 10.1186/1475-2891-11-67
Read the Full Text HERE.
Other sources of quercetin:
Fruits and vegetables -- citrus fruits, apples, onions, parsley, sage, tea, grapes, dark cherries, dark berries -- such as blueberries, blackberries, and bilberries, and olive oil.