Scientists believe that it does. It seems that people will often eat much more if a portion is labelled as regular or small, however, if a portion is labelled as large they will leave more food. I suppose it’s the fact that people often feel greedy ordering the large portion but feel they are being good when opting for the regular or small. Personally I find most food portions too large and will always order a small. If I want something else I will order dessert. This is why I’m fat it has nothing to do with the labels.