Like other sweet food, chocolate stimulates the release of endorphins, natural body hormones that generate feelings of pleasure and well-being. Chocolate contains over 300 chemicals and it is not known how all of these affect humans. Many women report particular chocolate cravings when pre-menstrual. This is possibly because chocolate contains magnesium, a shortage of which can exacerbate pre-menstrual tension. Similar cravings during pregnancy could indicate mild anaemia, which chocolate's iron content may help to cure. Chocolate also makes us feel good by reacting with our brains. (Source: http://www.bbc.co.uk/science/hottopics/chocolate/addictive2.shtml)

This type of effect is a possible scenario for the development of a physical dependency on chocolate. Current studies of psychoactive drugs show that addiction is associated with the formation and reinforcement of unusual neurotransmitter pathways in the brain. So it's just possible that, with every binge, your brain is being gradually 'rewired' in order to make you love chocolate more and more! (Source: http://www.bbc.co.uk/science/hottopics/chocolate/addictive2.shtml)

NEVER BE MORE THAN 12 STEPS AWAY FROM CHOCOLATE!
 (Source: www.virtualchocolate.com)

During the Gulf War, critical equipment flown out to US forces included a specially formulated heat-stable chocolate bar. But the jury is still out on whether or not it's good for us. (Source: http://www.bbc.co.uk/science/hottopics/chocolate/goodforyou.shtml)