Your mom’s old adage “eat breakfast like a king, lunch like a prince, dinner like a pauper” has some observational science to back it up, and the United States dietary guidelines recommend it.
http://www.wiscnews.com/baraboonewsrepublic/lifestyles/article_ae79dff2-68cd-5740-bb4a-3d9b70be4faf.html
Breakfast like a king?