Hi nana, I'm just now 3 months post-op bypass surgery. I've been tested and stay high with my protein and b levels. That will help you the most. I've just now started to notice some 'balding' areas in the front part of my hair and expected it. By month 4, it's possible I will have more hair loss but if it gets to be too much, just planning on a wig.
A lot of people cut their hair short before the surgery and I did the same. I think that helps as I can, for now, bring bangs down. Most any surgeon will tell you that it can happen but the best way to combat it is to just stay up on your protein. The vitamin B is another thing they will make sure you get enough of.
I am now 86 lbs lighter in 3 months (this includes the loss I had during program leading up to the surgery) and feel like a new person really. It was a tough recovery the first month but I'm so glad I did it. The hair loss is not a problem for me for this outcome.