I have heard too much testosterone can cause hair loss in men. Im 18 and male, with minor hair loss. Also where in the body is testosterone produced?

My husband is 24 years old.
His father lost most of his hair already, his older brother’s hair is thinning, and his uncles, while not bald, have very thinned hair.

This morning he noticed a lot of his hair on the pillow(not like patches, but still more than usual), and some more fell when he brushed his hair.
He hasn’t shaved his beard in almost a week, because I asked him to (I love men with facial hair), and now he thinks that might be the reason for the extra amount of hair fallen.
I figure that some of the hair on the pillow could be from his face, but he argues that itdoesn’t explain the one fallen from brushing…

Could stress suddenly cause hair loss?

What can be done to stop/reverse it?

(P.S.- I told him it doesn’t matter, it’s just hair, and I’d still love him, even with all his hair gone, but that only seemed to make him crankier. ? IDKY)
Is Rogaine recommendable for someone so young?
Should he start on Propecia, or some other med like it?
I am NOT leaving my hubby, just because he’s losing his hair!!!!

I grew up with a balding father, so I am more than used to a shiny head… I love them both with all my heart and their lack of hair won’t ever change that.
I’m only asking because he seems so upset, and it breaks my heart to see him worrying over yet another thing.
If there’s anything out there to help him, and make him happy, then I’m all for it…
He’s a very picky eater… He mostly eats fruits and veggies. He loves steak, but the leaner, the better (hates fat on his meat). Other than that he only eats chicken… Very, very healthy food… can his regular diet be contributing to the hair issue?
I don’t think he’ll go for an extra dose of "fat" in his diet…

My 21 year old friend is wondering what other causes for hair loss are there, besides: stress and genetics? He’s recently lost a significant amount of weight and has been told that can cause hair loss. Could that be why his hair’s thinning? And if so, will it grow back, etc?

Thank you!

I´m a 29 year old man and I´ve been indoor tanning for a couple of weeks and i feel my scalp kind of itchy. Can the hot air emitted by the lamps of a tanning bed cause hair loss?? If so how can i protect it, coz i don´t wanna quit tanning.
Hope you can help my guys. Thanks