Okay, now, don't go using this an an all-out excuse to have a hot fudge sundae for breakfast tomorrow morning.... but research keeps pointing to neurobiology as a major cause for the urge to overeat.
According to Dr. David Kessler and Passamonti, et al overeating is a biological challenge, not a character flaw. For most people, when they see a tempting snack like a potato chip, the area of the brain called the Amygdala lights up with activity and sends feelings of anticipation and desire. And once they start eating, the region shuts down.
But for an overeater the Amygdala remains activated while eating, creating that feeling of want and coaxing the desire even after 5, 10 or even 50 cookies. This can explain why some who've had gastric bypass find the weight creeping back on. Why others are hungry "all the time". Or why chocoholics like me can't seem to get enough Cadbury in a week. The Amygdala is also connected to emotional regulation and addiction - suggesting that much is knotted in this brain region.
I've always marveled at my mother-in-law who can have one cookie and be satisfied. Or a forkful of cake. Or stop at one potato chip. Yes, that's right. One potato chip. Her Amygdala regulates way better than mine.
But I am way better at Scrabble than she is.
Passamonti, L., Rowe, J., Schwarzbauer, C., Ewbank, M., von dem Hagen, E., & Calder, A. (2009). Personality Predicts the Brain's Response to Viewing Appetizing Foods: The Neural Basis of a Risk Factor for Overeating Journal of Neuroscience, 29 (1), 43-51 DOI: 10.1523/JNEUROSCI.4966-08.2009