From Science Daily
Supplements containing a patented phenol-rich extract of cacao beans protect the prostate while taking testosterone propionate, we wrote a few days ago. This is probably because the phenols in cacao inhibit the conversion of testosterone into the androgen DHT, researchers at the French research institute ETAP discovered.
The researchers performed a study for the Barry Callebaut Group, in which they used Callebaut's patented Acticoa, an extract of unroasted cacao beans.
In the previous article we wrote that oral administration of 24 or 48 mg Acticoa per kg bodyweight per day in rats inhibited the growth of the prostate as a result of testosterone propionate injections. In the previous study Acticoa administration started several weeks before the rats were given the testosterone injections.
In the study here, which was published in the Journal of Medicinal Food in 2007, Acticoa was not given to the rats until they'd been taking testosterone for a week. The researchers injected the rats with 2 mg testosterone daily. The simultaneous administration of Acticoa and testosterone propionate continued for two weeks.
The figure below shows that in this case too the cacao phenols inhibited the growth of the prostate. You can also see how the phenols probably work: they reduce the conversion of testosterone into its aggressive metabolite DHT. Many of the negative side effects of testosterone, such as prostate enlargements, increase in body hair and head hair loss, are to a large extent the work of DHT.
Acticoa or similar products can therefore in theory reduce the androgenic side effects of steroids such as testosterone, methyl testosterone and to a lesser extent boldenone and methandienone. Those steroids are converted by the enzyme 5-alpha-reductase into active steroids. So Acticoa doesn't help prevent the androgenic side effects of for example nandrolone, oxandrolone, oxymetholone, methenolone or stanozolol.
J Med Food. 2007 Dec;10(4):622-7.