Carole Hooven, Ph.D.

If you look at hunter-gatherers, they have like a high pathogen load.

They have fewer calories coming in.

They have high energy expenditure.

They have other stressful, energetically stressful situations to deal with that we don't necessarily.

So they keep their testosterone levels lower.

The peak is significantly lower.

I think it's like at least a third lower.

And then there's no real drop-off.

And they stay active and healthy forever.

relatively healthy throughout the rest of their lives and the testosterone, they don't have that 1% loss, say, per year.

And there's no problem with fertility, even though their levels are much, much lower than ours, which makes me skeptical about some of the explanations that

for the trend that we see of a drop in testosterone levels in men and a drop in fertility because it's definitely, if you look at these natural fertility populations, you see that we are starting out really high.

Men should not, I don't really see why there would be a reduction in fertility per se that isn't caused by other health issues, for instance.

On just the testosterone.

Yeah, it must be.

Because I think the testosterone must be declining because of all these other things that are affecting fertility.

Yes, phthalates.

Yeah, yeah, yeah.

Yes.

I don't know that that's been shown.