It is. Apparently the dopamine receptors in some of us don't work properly: http://www.takepart.com/article/2014/02/12/sugar-addiction In our brains, the dopamine receptor (D2, or DRD2 for short) must be switched on for us to feel pleasure. Sugar and other stimulating addictions inc  1000  rease dopamine in the short term for most people. The problem is that some people — those with sugar addictions, compulsive eating and obesity — have DRD2 systems that need much more stimulation to feel pleasure. A person with a sugar addiction, it seems, has fewer D2 dopamine receptors and needs extra stimulation (in the form of sugar) to make those receptors “turn on.” http://blog.gaiam.com/sugar-addiction-it-might-be-genetic/ In our brain, a little receptor, the dopamine receptor D2 (or DRD2 for short), must be activated or switched on for us to feel pleasure. The amino acid dopamine triggers this response. Sugar and other stimulating addictions increase dopamine in the short term. The only problem is it appears that those with sugar addictions, compulsive eating, and obesity have DRD2 systems that need much more stimulation to feel pleasure. Those who have sugar addiction, it seems have fewer D2 dopamine receptors and they need extra stimulation to make them “turn on”.(i) http://drhyman.com/blog/2011/02/04/stopping-addiction-to-sugar-willpower-or-genetics/ This would explain A LOT. The problem is that if you have it hard to be happy and get fat, you're fucked, because the fatness increases the depression symptoms, makes you feel worse, and at certain leves, stops you from using the most useful antidepressant: exercise.