We have all been there.It’s 3 o’clock and you’ve been hard at work.As you sit at your desk， a strong desire for chocolate overcomes you.You try to busy yourself to make it go away.But it doesn’t.A food craving(渴望) is a strong desire for a specific type of food.Most people have them even though what we crave might be different.But where do food cravings come from？ And how are they different from hunger?
Scientists compare hunger and cravings this way.Hunger is a fairly simple connection between the stomach and the brain.They call it “stomach hunger.”
A craving, however， involves several areas of the brain that make up the reward center of the brain.A craving can also be tied to our mental state and memory.So, some scientists call food cravings “mind hunger.”
Scientists add that while hunger is a function of survival, cravings are not.People often crave foods that are high in fat and sugar and not foods that can keep us alive.Foods that are high in fat or sugar release chemicals in the brain.These chemicals give us feelings of pleasure and—much like a drug.Studies show that our mental state affects our food cravings but not really our hunger levels.Also， our food memories affect what we crave and when.For example, if a child is given sweets when he or she feels sad or upset, that may lead to food cravings for sweets later in life.The reward system in the brain may lead us to seek out familiar pleasures.So, the next time you crave food from your childhood or have a desire for something very specific, know that your brain may be more to blame than your stomach.