Weight loss is also dependent upon the person. We all don't loose and gain weight with the same amount of ease and difficulty. If you can eat pizza and loose weight than great, good for you, but others cannot, regardless of how low their calories are. Weightloss is not as easy as you make it out to be for some people. As far as the carbs are bad "hype", my father lost a good amount of weight at the beginning of this summer by doing the Atkins diet for about a month, maybe a little longer. But regardless he started eating normal again and has kept the weight off. I really don't think he would have got the results he did by just limiting calories. Another thing about carbs and limiting calories is you have to take into consideration that not everyone weighs each bit of food they eat to determine how many calories are in them. You say you ate pizza. How many calories were in each slice??? How do you know that for sure?? You don't know how much of each ingredient the pizzeria puts in(assuming thats where you got the pizza), and last I checked pizzeria's don't have nutriotional guides telling you how many calories are in each slice. My point being is that it is very easy to unknowingly go over your maintence calorie range, so why not eat healthy foods(low carbs or low sat fats) to give yourself a little room to play with just in case you do eat something that is a little higher in calories than you thought. And also remeber serving sizes on the side of boxes are tiny compared to what we actually eat and many people don't realize that.