The Science behind Cravings

AUTHOR: MENOSHA SIVA

With the upcoming summery days, my mind is constantly filled with trying to find the best way possible to do something fun – be it learning to ride a bike at the ripe age of 21 or experiencing the cool, refreshing water of the Nordic lakes by finetuning my cannonball skills. However, there seems to be one incessant, nagging feeling in the back of my mind – cravings. The scorching sun somehow makes me crave ice creams, watermelons, colas and other sugary and delicious snacks. Naturally, that got me thinking, what is the reason I yearn for hot chocolate during the winter, and cocktails during the summer? In fact, why do I have random urges to eat chocolates regardless of the season?

I was glad to find out that I am not alone in my seemingly unexplainable cravings. Many people around the world tend to crave and indulge in their “guilty pleasure” foods. Statistically, 68% of men and a whopping 97% of women have experienced cravings at one point in their lives. Globally, the most common cravings include salty foods (think along the lines of potato chips, fries, buttered popcorn), chocolate, and fatty fast food such as burgers or pizza. This idea was based on the ”wisdom of the body” – a theory that the body knows what nutrients are deficient and pushes us to crave foods that are rich in said nutrients. However, this theory has been abandoned due to the overwhelming amount of research disproving it. For example, one study revealed that obese adults put on a low-carb diet for two years reported having significantly decreased cravings for carbohydrates and sugar. Furthermore, experts clarify that we tend to lose our appetites and veer away from our daily diets when we have a severe nutrition deficiency.

So then, why do we crave certain foods? Well, people tend to crave food that generally has a high calorie content, leading experts to believe there may be evolutionary connections. Thousands of years ago, food was much scarcer and hard to obtain. People had to hunt or cultivate their own food. Famine was rampant – almost as rampant as fast food chains in this day and age.

Therefore, it seems reasonable toconclude that we are geneticallypredispositioned to want high calorieitems and store the excess preciouscalories as fat to be used later on.

There is another biological factorplaying its hand in our urges to reachfor the seemingly sinful snacks.Humans and many other mammalsare driven by hormones. Ouremotions, bodily rhythms, and evengrowth is highly regulated by thesehormones; a deviation from normallevels will translate into a profoundeffect within our body. Upon scarfingdown a hearty meal, the hormoneleptin is secreted by fat cells andsignals to our brain that we are full.However, have you ever eaten alarge meal, only to find out youmiraculously have some room left fordessert? This is because seeing,smelling, or hearing about dessertcan trigger your brain’s rewardcentre (which includes the ventraltegmental area, the nucleusaccumbens, and the prefrontalcortex) while simultaneouslyreleasing dopamine. Therefore, justby the thought of a soft, oozy, warmchocolate cake, your mouth starts tosalivate as you crave that rush ofdopamine. By that point, it’s a battleof leptin versus dopamine, and it’snot a fair game.

On a similar note, two other hormones play a crucial role in triggering cravings: ghrelin and peptide YY. Ghrelin is famously known as the ‘hunger hormone’ as it stimulates the urge to intake food. Peptide YY, on the other hand, reduces appetite. For those night owls out there, you might want to learn about a recent study in the Journal of Sleep and Biological Rhythms that found a correlation between sleep deprivation and a change in the hormone levels indicative of obesity. This suggests that our actions, directly or indirectly, can also be a culprit in inducing our cravings.

Nevertheless, getting enough sleep is not the only thing you can do to keep your cravings at bay. Eating more protein, meal planning, managing stress, and eating before grocery shopping can all help to deter you from caving in to your pesky cravings. While the theory of ”the wisdom of the body” has been debunked, mindful eating combined with a healthy diet may help to deal with cravings. John Hopkins’ Bariatrics department even has an online questionnaire that can help one distinguish between hunger and cravings, while providing tips on mindful eating.

However, if you’re craving non-food substances, you may want to check if you suffer from pica, a compulsive eating disorder commonly found in pregnant women and preadolescents where people crave and consume non-food items. In this case, please reach out to a medical professional.