I agree with robin and Jay.
It is calories in vs. calories out...BUT, I not only want to be thin, but I want to be healthy. I want to have good muscle mass, low cholesterol, keep my blood sugar under control, have plenty of the properties from fruit and vegetables that ****** aging, fight cancers, and beautify the skin, hair, etc.
I want to be HEALTHY.
There is nothing wrong with having an occasional slice of pizza, or a small square of dark chocolate now and then. BUT-these foods were meant as treats, not meant to be eaten every single day. Also, if you are on a low calorie diet, let's say of 1500 calories a day, and you have a 750 calorie hot wings platter or two slices of meat lovers pizza for about the same calories...then you just ate HALF of your daily calories in crap. That isn't moderation.
I like to follow the 10% rule. If you are going to have treats, then it should be about 10% of your diet. For 1200 calories a day that is 120 calories, for 1400 calories a day that is 140 calories, etc. This is if you have to have a small treat daily. If you eat clean all week long, then having something on the weekend that is 300-400 calories isn't bad. It is still moderation. But-having pizza, alcohol, chicken wings, and milkshakes on a daily basis isn't moderation.
Because I am very active with exercise, teaching dance classes, etc. I cannot live on junk. I can't eat chocolate for breakfast and pizza for dinner and "make it" on that. I wouldn't be giving my body enough protein anyhow, to fuel my muscles with enough protein, either-which would make my working out with weights unproductive. Lifting weights is kinda like building something with tools. I can go through the motions, but if I don't have the materials to build with (good sources of protein) then I don't end up with anything. It's like trying to build a clubhouse for your children without wood.