Men and Hairloss?

My husband is thinking about sleeve surgery now that he's seen my success with mine. He's overweight with terrible back problems. His reason mainly to get it done would be to cut down on the back pain. He asked me today if there are many men on this forum. I asked why and he said that he'd like to know if the surgery caused them to lose their hair. His is already thinning and he's super sensitive about it. I told him that as long as he eats his protein he should be alright. I've honestly lost a little bit of hair myself but I have a tough time getting all of my protein in every day. Anyway, are their any men out there that could give me some advice for him?