We've all experienced food cravings, the feeling that we don't just want to eat something -- we want something very specific. Researchers at Tufts University found that the types of foods people crave are individual, but generally speaking, people crave foods that are high in calories. For a better understanding of food cravings, it's important to understand what influences our cravings and what we can do to control them.
In the May 2010 issue of Current Directions in Psychological Science, a journal of the Association of Psychological Science, psychologists Eva Kemps and Marika Tiggemann of Flinders University, Australia, reviewed the latest research on food cravings to answer one question: Why do we get intense desires to eat certain foods? They found some studies suggesting that the mental imagery of food (the vivid images we get when we crave) hold the key. In fact, one study found that the strength of an individual's craving was correlated with how vividly they imagined the food.
If this is the case, then the media may play a large role in determining what we crave. Considering that children in the U.S. are exposed to approximately 5,500 food commercials from television each year -- 98 percent of which are promoting products that are high in salt, fat and sugar -- it's no surprise that in a study published in Health Psychology by Dr. Jennifer Harris and colleagues at Yale University, researchers found that children and adults who watched advertisements for snack foods ate significantly more than those who were not exposed to ads (children ate 45 percent more and adults ate 33 percent more).
Aside from the media, what we crave may also be a preference we are born with. What our mothers ate during their pregnancy has a big impact on our food preferences. Julie Mennella, a biologist at the Monell Chemical Sciences Center, found that as babies grow in the womb, they begin to ingest up to a liter of amniotic fluid a day, leading to exposure to flavors that he or she will prefer as an infant. For her study, Mennella gave one group of subjects carrot juice four times a week and switched to water when breastfeeding, gave the second group water during pregnancy and switched to carrot juice when breastfeeding, and gave water to the third group when pregnant and breastfeeding. When the babies were five months old, the researchers gave the infants plain and carrot-flavored cereal, only to find that babies who had been exposed to carrot juice while in the womb were more willing to eat carrot cereal.
An alternate theory lies in the kinds of food we eat, specifically contrasting "health" foods with "indulgent" foods. New research from Yale University has found that when people eat healthy food -- regardless of how many calories consumed -- their stomach signals less satisfaction.
Researchers in the study focused on the hunger hormone called ghrelin, which stimulates one's appetite. Not surprisingly, ghrelin levels typically increase before meals and decrease after meals. The higher the levels of the hormone, the more likely it is that a person will overeat.
Participants in the study were given identical shakes in order to test whether physiological satiation, as measured by ghrelin, may vary depending on the mindset in which one approaches the consumption of food.
On two separate occasions, participants consumed a 380-calorie milkshake under the pretense that it was either a 620-calorie "indulgent" shake or a 140-calorie "sensible" shake. Ghrelin was measured via intravenous blood samples at three time points: baseline, anticipatory and post-consumption. During the first interval, participants were asked to view and rate the (misleading) label of the shake. During the second interval participants were asked to drink and rate the milkshake.
The amount of hunger hormones released before consuming the "indulgent" shake was higher than the amount released before drinking the "sensible" shake. Participants who consumed the shakes perceived as being more indulgent, reported greater satiation afterward. In other words, if you think of the food as being decadent or indulgent, you might feel more satisfied.
Participants' satiety was consistent with what they believed they were consuming rather than the actual nutritional value of what they consumed. Therefore, state of mind may have influence over what makes a person feel satisfied after a meal.
If you want to keep your cravings at bay, then consider what research has found. When you understand the culprits behind cravings, you can help control them. Remember, don't be a slave to the foods you crave!
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