Tucking into that big bar of your favourite chocolate could keep the blues at bay but a new study has shown that chocolate has an effect on the brain similar to opium. It highlighted the striking similarity between obese people and drug addicts. In the study a natural brain chemical called enkephalin - an endorphin with similar properties to opium - surged as rats began to eat M&M chocolates. When the dorsal neostriatum was stimulated the area that releases the chemicals showed a marked increase in activity causing the rodent to eat more number of M&Ms. In the brain enkephalin
