Do bunnies shed periodically?

My bunny has been shedding for a week now. Its not bundles and bundles of fur, but whenever I pet him, fur starts flinging off. I don't think its parasites because he's not itching alot. The only thing I can link the shedding to is the GRADUAL diet change I have been doing (I am decreasing his pellet intake a little bit each week, he was looking a bit chubby :) ) But my other bunny isn't shedding, and she's on the same diet as he is. Could there be an internal malfunction thats making him shed? Or something else? Other than shedding, he's completley normal (shows no signs of lethargy, loss of appetite, etc.) *I'm a new to the bunny business, so please don't scold me if I am doing something wrong. Helpful advice is greatly appreciated :)