I lost a little weight (10 lbs or so) while commuting. I lost a further 30 lbs when I sold my truck and started cycling everywhere. Currently, I can eat pretty much what I want so long as I don't stuff it in and I maintain. At 35 calories a mile averaging 20-30 miles a day at least 6 days a week plus the 1800 calories it takes for a 200 lb man to maintain, that's a lot of calories I get to enjoy!