What can I use for gaining weight? I'm 17 MOS out gastric bypass and I lost almost 40 pounds being sick on top of the 120 lb from my surgery 1/18/18 I'm barely over 100 I lost my c cup boobs pneumonia and I got powder from GNC yuck I paid 40$ a bag whey protein the one body builders use. Sent from my moto e6 using BariatricPal mobile app