Cheese 'can be as addictive as morphine': "An American doctor has claimed that cheese can be as addictive as morphine.

Dr. Neal Barnard, president of the Physicians Committee on Responsible Medicine, says cheese is addictive because it contains small amounts of morphine from cows' liver.

In his book - Breaking the Food Seduction: The Hidden Reasons Behind Food Cravings and Seven Steps to End them Naturally - he explains why people are hooked on products like cheese, meat, sugar and chocolate.

He says: 'There's a biochemical reason many of us feel we can't live without our daily fix.

'Cheese, for example, contains high levels of casein, a protein that breaks apart during digestion to produce morphine-like opiate compounds, called casomorphins.

'These opiates are believed to be responsible for the mother-infant bond that occurs during nursing. It's no surprise many of us feel bonded to the refrigerator.'

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