A food craving is an intense desire to consume a specific food, and is different from normal hunger. It may or may not be related to specific hunger, the drive to consume particular nutrients that is well-studied in animals. In studies of food cravings, chocolate and chocolate confectioneries almost always top the list of foods people say they crave; this craving is referred to as chocoholism. The craving of non-food items as food is called pica.
Causes
There is no single explanation for food cravings, and explanations range from low serotonin levels affecting the brain centers for appetite to production of endorphins as a result of consuming fats and carbohydrates. Foods with high levels of sugar glucose, such as chocolate, are more frequently craved than foods with lower sugar glucose, such as broccoli, because when glucose interacts with the opioid receptor system in the brain an addictive triggering effect occurs. The consumer of the glucose feels the urge to consume more glucose, much like an alcoholic, because the brain has become conditioned to release "happy hormones" every time glucose is present. The cravings for certain types of food are linked to their ingredients. Chocolate for example, contains the neurotransmitter phenylethylamine, which is important for the regulation of the body’s release of endorphins.
Pregnancy
Women will often experience cravings for seemingly random foods during pregnancy. The reason that these cravings occur is not definitively known. It's been theorized that these cravings might be in order to replace nutrients lost during morning sickness. However, there is substantial evidence that pregnancy cravings serve a social function, rather than a nutritional one. Because popular pregnancy cravings differ in their nutritional make-up from culture to culture, it can be inferred that there is no set of nutritional needs that these cravings are filling. Instead, it may be that strange cravings help pregnant womensignal that they are pregnant and recruit help from the people around them. Some decent evidence for this is the fact that women often crave rare, hard to obtain foods and reject common-place, everyday ones. Providing pregnant relations with food may have been common among the human ancestorHomo Erectus, which provides a possible explanation for the evolution of this behavior. Different cultures have different popular pregnancy cravings. One of the treatments for morning sickness consists of accommodating food cravings and aversions. Depending from the historical period and the culture there are different traditions regarding pregnancy cravings. Some examples are:
During pregnancy Hmong women would follow their food cravings to guarantee that their child would not be born with a deformity.
In the Babylonian Talmud, folio 82a of Tractate Yoma mentions pregnancy cravings for non-kosher food as the paradigmatic example of a presumed life-threatening situation where a person is allowed to eat non-kosher food.
In the Philippines, the condition is traditionally known as lihi, and it is believed that traits of a food that a pregnant woman craves and consumes is imparted to the child. This also extends to objects or people that a woman would find pleasurable to see during her pregnancy.
In Thailand a woman who starts craving sour foods after her period has stopped is deemed to be pregnant.
"Chocolate craving"
Chocolate is seen as a sweet that is desired more by women than by men. Studies conducted in the UK and US and Canada have concluded that women indeed crave chocolate more than men. Also this chocolate craving seems to occur more perimenstrually. However a biological explanation has not been scientifically proven. It seems to have a cultural cause instead of a biological cause. Spanish women experience perimenstrual chocolate craving far less than American women although they should not differ much physiologically. Spanish females crave chocolate more after dinner. The times males crave chocolate also differs between both cultures but was the same as the craving for chocolate of females in their culture. For treating small chocolate cravings, the smell of jasmine has been known to work.
