Claims this article which suggests tiredness causes you to crave high calorie foods. It seems that poor or no sleep results in raised levels of a hormone that is linked to boosting hunger. This doesn’t really come as a surprise to me. After nearly a week of more broken sleep with one or the other of the children being up in the night I have found that I really crave a chocolate bar or a fizzy drink, things that I usually don’t eat. Certainly the lack of sleep makes me seek out surgery treats.