Actually, the data on selenium is mixed, and it hasn't been shown to be harmful on its own. In fact, none of the ingredients have been shown to be harmful, or of any benefit, on its own.
In a similar randomized controlled trial (Phase 3- n=423) of the use of selenium alone in men with HG-PIN, supplementation with selenium was found to have no effect
on the later development of prostate cancer. Three-year cancer rates were 37% for the placebo versus 36% for those taking selenium supplements - no significant difference.Phase III Trial of Selenium to Prevent Prostate Cancer in Men with High-grade Prostatic Intraepithelial Neoplasia: SWOG S9917
In the follow-up to the SELECT trial, there were three conclusions about
(1) Selenium supplementation did not benefit men with low selenium status
(2) Selenium supplementation increased the risk of high-grade PCa among men with high selenium status
(3) Vitamin E increased the risk of PCa among men with low selenium status.
So. it's only when selenium is taken when serum selenium is already high, or when it is low and taken together with vitamin E that there appears to be harm.Baseline Selenium Status and Effects of Selenium and Vitamin E Supplementation on Prostate Cancer Risk
As for green tea catechins, a similar RCT of that alone (400 mg EGCG per day) found it "did not reduce the likelihood of PCa in men with baseline HGPIN or ASAP."Randomized, Placebo-Controlled Trial of Green Tea Catechins for Prostate Cancer Prevention.
As for lyc
opene, a recent meta-analysis of all the studies done on it found there was no statistically significant benefit associated with consumption of raw tomatoes, cooked tomatoes or lyc
opene.Lycopene/Tomato Consumption and the Risk of Prostate Cancer: A Systematic Review and Meta-Analysis of Prospective Studies
Based on this, one can't simply conclude "it was the selenium." No one can know whether the combinations of any two or all three were harmful. And what are the interaction effects with other supplements? In light of the potential harm, and no proven benefit to any
of the ingredients, why would anyone risk it?