Low T

Some few years ago, British researchers found upon the autopsy of every single male who died in
their country for decades, that each man over 40 had prostrate cancer. Most died of something
else, because most of these cancers grow too slowly to kill.
The medicine for prostrate cancer is essentially female hormone.
Supplements companies are marketing things to curb prostrate illness.
Why, however, are other companies marketing testosterone to middle aged men? Shouldn't there
at least be some disclaimers, some warning, in the advertising?
Some forms of this cancer are so virulent, a man can be dead within months of being diagnosed.
Who is monitoring American marketing? Venture capitalists only?