I have been thin all my life, and am currently trying to gain weight. So I eat a lot, and often, and I'm lucky to see a pound a month of weight gain, if that. But when I cheat (infrequently) and have a slice of bread, some pizza, or (last night) some cupcakes at a wedding, I am guaranteed to be up 3# the next day, and for several days after.
For those that cheat once in a while with wheat, have you seen this? I eat potatoes, rice, and sweet potatoes fairly often and never see this effect from them.