When things go bad, people -- especially women -- often turn to food. When there's no one to cuddle, a pint of ice cream does the trick.
Comfort food really does comfort. And it does it by evoking the same physical responses that does.
Oxytocin is central to feelings of love and being loved, and it's just a central to the feeling of satisfaction that comes from a good meal.
In the brew of digestive juices that turns your burrito into energy is the digestive hormone cholecystokinin (CKK). When food reaches the small intestine, CKK sends a message to the brain. The brain, in response, secretes oxytocin, suffusing the body with the feeling of contentment. Fatty foods stimulate more CKK production, thereby making us feel more satisfied. That's why ice cream is more comforting than asparagus.
But there'd another reason why we reach for ice cream, not asparagus, when we get the blues. Our infant brains learn to associate milky food with the live and safety we feel in our mother's arms. Breast milk, rich with fat, causes the secretion of high levels of CKK and, in response, oxytocin.
Being held while we nurse conflates the physiological response to food with the feeling of being loved. In fact, when French researchers blocked the effect of CKK in newborn lambs, they lost their preference for their mothers.
Sometimes, our bodies can't really tell the difference between ice cream and a hug.