Why modern men are losing their testosterone Posted by basicplus2 on Saturday December 15, 2018 @07:45PM from the bigthink.com dept. https://bigthink.com/sex-relationships/men-have-less-testosterone-today ( 2 comments | 5 points | on HN )
Note, that's an animal study, but definitely worth considering if you're worried about your T-levels.
Another thing to look at if you want to raise your T-levels: High intensity training [0]
[0] https://www.researchgate.net/publication/317013787_Exercise_...