I am beginning to wonder if there's something to the hypothesis that testosterone levels have declined considerably over the past century.
Yes this is true I read a study over 15 years ago showing that in Japan some 30 years earlier young men all had well over 1000 for TT and they showed how much it had dropped thru the last 30 years. There is no question about this as far as I've read. They concluded this was a world wide problem and was likely related to pollution and diets. However, I have not read about this for some time. My guess is that it's not just testosterone that lower than a century ago it's all our hormones.