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The thought of melted ice cream trickling down your spoon.. the creamy, rich, mouth-watering flavor of every bite. Thinking about it makes you go crazy as you want nothing else. You just need to have that ice cream. You think you crave that ice cream but is it the taste that you crave? Do you maybe crave it for its pleasant associations and memories? Or maybe simply the thought of not being able to have it makes you want it more and more? But it is all okay because you are really strong-minded and you can easily fight the urge…. Or can you? Will fighting the urge make the craving go away or will it cause you to want that craved food more and more?

The science behind cravings is a difficult one. Different studies are constantly being conducted showing some interesting results. This article will try to clarify exactly what causes food cravings and hopefully will give you an idea on how to stop food cravings.

Multiple studies report that men have less food cravings than women do. One study reported that men prefer meal-related foods such as steak while females enjoy comfort food such as chocolate and ice cream. Women also have been shown to feel guilty after indulging in such cravings while men report feeling quite satisfied. So what does this mean? Is there some kind of science behind this? Maybe men crave steak so they can get protein to allow for their big manly muscles and physique? And maybe women crave chocolate because they are low in magnesium or phenylethylamin (both are found in chocolate). And do women feel guilty because of something innate or because they know that chocolate and ice cream are high in calories and can potentially cause them to gain weight, which is looked down upon by our society? Men may feel good about themselves after eating a steak because eating big meals and lots of protein is viewed positively in our culture and is encouraged.  The same study also showed that younger people prefer snack-related food more so than those over the age of 55.

So is there physiological reason for pregnancy food cravings? What causes food cravings during pregnancy?

While it is well known that during pregnancy many women report many specific and often weird cravings, studies continuously find little validation for physiological causes of these cravings. It is suggested that the extreme changes in hormones during pregnancy has a huge impact on taste and smell, which is a possible cause of strong pregnancy food cravings. Studies have shown that pregnant women who experience aversions are much more likely to experience food cravings in comparison to those who do not experience aversions. Pregnant women have also been found to prefer sweet tastes over salty ones.  No studies, however, have been able to find a link between pregnancy food cravings and nutritional requirements. It has been believed that pregnant women crave certain foods that their body and the baby need for optimal health, but unfortunately, new research is displaying different results.

So what causes food cravings? Are there physiological causes of food cravings?

So wait? There has to be some positive reason that we crave certain foods, right? Maybe I crave that piece of candy or fruit because I have low blood sugar and it is my body’s way of raising my blood sugar to healthier levels. Or maybe I just I had a really good workout and my muscles are screaming for protein to rebuild and repair so I start to crave a nice succulent chicken. But if our minds were so smart and we crave foods that we really needed, it makes no sense that we constantly crave foods that are unhealthy for us. I do not hear many people craving some nice spinach leaves or a kale smoothie when they are lacking certain essential vitamins and minerals. So if we do not crave foods for physiological purposes, then what causes food cravings? Research is showing more than ever that we crave foods because of social, cultural, and psychological factors.  In America, chocolate is a common craving among Americans. However, other countries are shown to have different cravings. In a recent study, Japanese women were shown to crave sushi while many other Asian countries craved rice suggesting that the craving for food is influenced by the specific foods we eat and the cultures in which we associate with.

In another survey, only 6% of Egyptian women reported any sort of craving for chocolate. Actually, only 64% of languages even have a word for “craving.” So it is quite possible that cravings are more of a cultural thing than anything.

Are hormones to blame for cravings?

Approximately half of women in America crave chocolate and about half of those cravers crave chocolate at about the onset of menstruation. A study conducted by the University of Pennsylvania wanted to investigate the cause of perimenstrual craving and see if women crave chocolate in response to stress and other events or because of a direct hormonal effect. To test this they examined the chocolate craving levels of women post-menopause. If the cravings were truly a result of hormones then there should have been a 38% drop but the results of the study only showed a 13% drop in cravings, suggesting that the reproductive hormones of females are not the main cause of perimenstrual chocolate craving. Possibly a greater explanation for women craving chocolate is the release of chemicals that cause “good” feelings such as serotonin.

Can we really crave a food without actually liking it?

So it is clear that we often crave things that we really enjoy, but what about things that we don’t enjoy? Research suggests that it is possible to crave a food without actually liking it and like a food without actually craving it. In a study conducted in 2004, subjects were given a vanilla flavored Boost protein drink for five days to see how much they really craved another food. After the 5 days, the subjects began to crave those protein shakes after returning to their original diets.

Cravings appear to be caused by repetition and habit more than anything. In a study published in 2011, obese subjects were randomly assigned to a low carbohydrate diet or a low fat diet for two years with the goal of the study being to evaluate the effect of low carb diets and low fat diets on food cravings, food preferences, and appetite. The results of the study showed that the subjects on the low carb diet had much lower cravings for starchy carbohydrates (brown rice, cracked wheat, popcorn, barley, oats, etc), high carb, and high sugar foods. The low fat group, on the other hand, showed severe decreases in cravings for high-fat foods and showed decreased preferences for low carbohydrate and high protein foods. In conclusion, the study showed that restriction of certain types of foods resulted in decreases of cravings and preferences for the foods that were being restricted. Also, the study indicated the low carb group was significantly less bothered by feelings of hunger than the low fat group.

Another study conducted in 2009 showed similar results. The study focused on the relation between the intake of specific foods and food cravings. As shown in the study I listed above as well, the food cravings were significantly related to food intake with precise food cravings being correlated with the types of foods eaten. Cravings for fats were directly related to the intake of high fat foods while cravings for sweets showed a positive correlation in association with jelly beans and M&Ms.

Does dieting cause food cravings?

In a two-phase study conducted by Leeds University, 206 women filled out the Dutch Eating Behavior Questionnaire, the Three-Factor Eating Questionnarie, and a food-craving scale. A correlational analysis was then conducted showing food craving to be only weakly related to dietary restrictions. Phase two of the study used 10 women who reported regular food cravings and ten women who reported rarely experiencing food cravings. The “cravers” consumed only slightly more food than the non-“cravers” and there were very few differences in eating behavior.  In conclusion, the study showed that food deprivation is not a necessary condition for the manifestation of food cravings as food cravings tend to be more closely associated with mood.

Food cravings may be quite similar to drug cravings?

Recent evidence is showing that food cravings is actually quite similar to drug cravings. In a study using a fmri scan, food craving was analyzed and studied. The fmri scan identified craving-related changes in the hippocampus, insula, and caudate, three areas that are known to be involved in drug craving. This whole circuit is driven by dopamine, which is the neurotransmitter in the brain that is accountable for learning that is driven by rewards.  Although cravings are not very harmful when indulged in on rare occasions, constant cravings can be quite destructive. When we constantly overwhelm our reward circuits with unhealthy foods, drugs, and alcohol, our dopamine receptors shut down to prevent overload. This deactivating of dopamine receptors causes us to crave more and more, which is why we go from needing one piece of cake to satisfy our cravings to needing 2 or 3 pieces. And even when we eat more and more to try and satisfy our cravings, we still do not feel satisfied.

What impact does sleep, or more specifically, lack of sleep, have on food cravings?

Another factor that seems to cause a big increase in food cravings is lack of sleep. There has been a lot of research that has associated being tired with overeating, which in turn leads to weight gain. When we do not get adequate sleep, our circadian rhythms are thrown off and our metabolism becomes less efficient. In 2012, there were two studies that were presented at the SLEEP 2012 conference in Boston that showed the correlation between sleep and food cravings.

The first of the studies was at Columbia University. This study found that a lack of sleep had a great effect on the way our brains respond to food, and more specifically junk food. The study consisted of 25 healthy men and women. They were all given brain scans after 5 nights of sufficient sleep of up to 9 hours each night or after sleep deprivation of about 4 hours a night. Using functional magnetic resonance imaging, or fmri, the study’s participants had their brains scanned while they were given pictures of unhealthy or healthy foods to look at. The researchers found that the networks of the brain most directly associated with reward were much more active in sleepy people. And these activated reward centers were more were much more active in response to junk food such as pizza and cake than in response to fruits and vegetables. The researchers from this study theorize that when we don’t get adequate sleep, our bodies may seek high calorie foods naturally to help them make it throughout the day.

The second of the studies was at conducted at the University of California, Berkeley. This study found that sleepiness appears to impede the brain’s complex functions such as decision making, which would cause sleep-deprived people to not to be able to resist that 2 am Jack in the Box meal. As in the Columbia study, researchers at Berkeley used an fmri to monitor brain activity. The brain activity was evaluated in 23 healthy adults twice, one of which after a normal night’s sleep and the other after zero hours of sleep.  During both scans, they were told to rate how much they wanted different food items to appear during the scan. Unlike the Columbia study, the results did not show that the reward centers of the subjects did not respond more strongly when sleepy. Instead, the researchers found that when the participants experienced sleep deprivation, their frontal lobe’s brain activity (the region that helps control behavior and monitors the ability to make complex decisions) was impaired. This study suggests that overeating occurs at night because our sleepiness prevents the brain from being able to make rational decisions when weighing the pros and cons of different foods leading us to consume more junk food than healthy food.

Tips to allow you to learn how to stop food cravings

So it is clear that cravings are not beneficial to our health but how do we stop them? Many studies have shown that resisting the urge actually increases the craving. So instead of trying to resist the urge, a better idea may be to embrace and control the urge. The studies listed below will give a better idea on how to stop food cravings.

A study performed in London in 2003 showed that subjects who ate chocolate in the middle of the meal or after the meal were more successful at giving up their craving than those who ate chocolate on an empty stomach. This suggests that it might be a good idea to eat the foods you crave when you are full. If you want to try to ease your intense food cravings, eat a nice full meal and see if you still have those same strong cravings.

In another study conducted in Australia, cognitive behavior therapy was found to be useful in stopping strong cravings for food.  110 self-proclaimed cravers of chocolate were given a bag of hershey’s kisses to carry around for a week. Half of them were given “cognitive restructuring” where their thoughts about chocolates were challenged while the other half were instructed in “cognitive defusion” where they were taught to observe and accept their thoughts about food cravings without actually acting on them. At the end of the study, the group told to observe and accept their thoughts without acting on them ate three times less chocolate than the “cognitive restructuring” group.

Exercise has also been shown to help with food cravings and is a good idea when learning how to stop food cravings.. In a study conducted at BYU, women who exercised with moderate-to-vigorous exercise for 45 minutes in the morning showed a decreased brain response to images of food.

When it comes to any addiction, whether it be food, alcohol, drugs, tv, etc., the first step is awareness. Once you become aware of your addiction (or in this case, your food craving), the next step is realizing that you do not have to act out on your addiction. Become aware that this addiction/craving is a part of you. When you feel your craving coming on strong, take deep breaths and welcome your craving. Do not push it away and repress it. Do not treat it as something not a part of you. Accept it and allow your craving to transform and eventually it will no longer be a craving. It might even be a good idea to set a timer for half an hour whenever a craving starts to arise. Keep yourself busy for that half hour until the timer goes off and by that time the craving may have even passed. Just remember that although you cannot control your cravings and addictions, you can control your actions.

If you have any questions or comments regarding  food cravings, do not hesitate to let us know by either leaving a comment or sending us an email at phenom.fitness.and.health@gmail.com

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