Your best bet is to see a Dermatologist. My hair started thinning about three years ago. I used rogaine for awhile but saw no noticeable difference. My Dermatologist diagnosed me with Alopecia and rogaine wont help. However, I do use a shampoo called Nisim which has biotin in it and slows the shedding to a minimum so I keep what I have basically. Also I am on Spironolactone which is a diuretic and antiandrogen. Spironolactone is very effective and is prescribed by your Dr. Although my hair loss is due to Alopecia, yours may be from weight loss itself. Spironolactone is used by anybody who is experiencing hairloss, it is a good choice. Hope that helps