Steroids seem to have a triple-whammy effect on weight gain.
1. Increase hunger
2. Fluid retention
3. Increased hunger or fluid retention
Yeah, I know that's technically only a double-whammy, but sometimes one or both symptoms are so intense they deserve double-billing. Sometimes, it almost seems like a quadruple-whammy.
I have autoimmune disease, so am on periodic courses of prednisone. I definitely have a love-hate relationship on prednisone. One one hand, it makes me remember what it's like to feel energetic and active (I don't have a problem getting exercise in when I'm on prednisone), but I feel like I could eat the entire world and still be hungry enough to eat another planet or two - and then there's the weight gain.
I can easily gain 9 pounds of water weight with prednisone - but if I'm on it for more than a month - some of the weight tends to be true, fat poundage.
I'm so hungry it takes superhuman effort not to eat - but therein lis the trap. Because it feels like I'm not eating far more often than I am eating, it doesn't seem possible that I'm eating enough to gain. It feels like I'm being more strict with my diet than "normal" because of the extra hunger.
It just doesn't seem possible to gain weight and still be so hungry all of the time.
Sugary and starchy carbs (which tend to always be a bit of a problem for me)
are even more of a problem during a course of prednisone. I seem to be able to get through a course of prednisone without a true gain (not just water) only if I eat very low carb during it.
As much as I believe that restricting carbs is the answer for me (both on and off prednisone) - I don't think it's the answer for everyone. I'd try South Beach style eating before deciding to restrict carbs further, but that's just my two cents (if it's even worth that).