Cycling brought my weight down to what it was when I was a teen. If anything, that's made me less concerned with my diet as I'm not worried about weight anymore. That means no guilt with that third bowl of ice cream. I know I eat too much sugar and salt. I don't really care, except that I wish I could eliminate high fructose corn syrup from my diet as I have an feeling (unsupported by much of anything) that that crap is killing us all in ways no one yet realizes.
I hadn't eaten breakfast or lunch in many years, but after the weight loss that came when I started riding I did find myself getting hungrier during the day. So I'll often eat a Clif bar for lunch now, which is probably a positive change.