You’ve probably heard that food cravings have little to do with true hunger, but if they aren’t a part of our biological need for fuel, then how do they work? What kinds of foods do you “crave” when you are stressed or upset? Are they sweet or salty? Loaded with carbohydrates? Packed with fat? Drizzled in chocolate?

First, let’s talk about why these specific foods and macronutrients (e.g. carbs, protein, and fat) are commonly craved and then we can sift through some helpful ways to overcome the urge.

chocolate cake

So where do cravings come from?

Cravings are separate from true hunger, which comes on slowly and may have more of a physical effect (fatigue, stomach rumbling, dizziness).  Most of the time, when we are truly hungry we have an open mind about what foods we’d like to eat. There are specific signals that help the body tell the brain when it’s ready for more fuel. However, the relationship is complicated and there are quite a few factors involved. You’ve probably heard of these two: Ghrelin and Leptin.

 

Hunger Messengers (Hormones)
Higher BEFORE eating

When your body realizes that it needs food, it will release the hormone ghrelin into your bloodstream.  High levels of ghrelin will trigger symptoms of hunger.

Higher AFTER eating

When your body realizes that it has had enough food, it will release the hormone leptin into your bloodstream.

Ghrelin

Tells your brain that you are hungry

Leptin

Tells your brain that you are full.

Signals energy balance to the brain

 

Cravings have both biological and psychological components. A craving is an intense desire to eat a specific food. A craving, or “emotional hunger” comes on suddenly, usually for a specific food, is often mindless, and eating what you’re craving won’t always lead to satisfaction.

Environmental Cues

pepperoni pizzaA Big Mac on a billboard, the aroma of coffee in a small café, or fresh bread in a bakery – images and smells everywhere remind us of the fantastic substances available to eat and drink. Food is all around us – and despite a growling from your mid-section, these cues can make you think you’re in need of some Hot-N-Ready® pizza.

Emotions

We crave certain foods when we feel sad, stressed out, or upset. The culprit? Our very own mind… and body. Hormones and neurotransmitters are messengers our bodies use to communicate with our brain (and visa versa).  Both of these internal signals are needed to perform thousands of functions.

But what do they have to do with cravings? In all honesty, cravings are still sort of a mystery to science. What we crave and why we are craving it also varies from person to person – we are all different. This makes cravings difficult to study. There isn’t really one single cause to determine why all the sudden we want pizza with black olives, or ice cream with hot fudge.

These neurotransmitter signals come from our brain and our gut to help control our appetite and mood. Like mentioned before, we have internal signals that tell us when we are hungry and when we are full (Ghrelin and Leptin, respectively (and about 12 others)). We also have internal signals that reward us with pleasure when we eat certain foods (Dopamine and Serotonin). So, we have “hunger signals” and “feel-good signals “– both related to the food we eat.

 

“Feel-Good” Messengers
Dopamine

Helps control the reward and pleasure centers in the brain. It also helps regulate movement and emotional responses.

Serotonin

Contributes to feelings of happiness. Most of the body’s serotonin is found in the GI tract and it functions largely in the brain. It affects mood, appetite, sleep, memory and learning.

 

It’s no wonder dopamine and serotonin are linked to food cravings. If certain substances (sugar, fat, carbohydrates or salt) bring pleasure to our brain – then of course we may occasionally crave them.

 

Curb the Crave

 

Get Enough Sleep

A study by The Journal of Clinical Endocrinology & Metabolism suggests that not getting enough sleep may alter the way leptin communicates with your brain. When leptin isn’t working right, your body may think it’s not getting enough calories – hence the desire to eat more food.

Drink Water

This one can help with hunger AND cravings. Sometimes thirst can be disguised as hunger. Before you peruse the pantry, drink a glass of water and wait awhile.

Entertain your brain

Find something actively entertaining: play a game, do a crossword puzzle, go for a walk – are you ever “hungry” because you are bored?

Relieve Stress & Tackle tension

High levels of stress can contribute to cravings. We often use food to help us cope with stress (comfort food → feel-good messengers → Less stress). Find ways to relieve stress that won’t add unnecessary calories. Relax, exercise, and/or read a book –what works best for you?

 

But what if it’s more than a craving?

Since research suggests that these types of foods make us feel good, eating sugary foods [or salty, or fatty foods] can lead to an addictive-like eating behavior. We’ve established that cravings have a physiological impact, but are they actually addictive? Check out Paige’s article “Can you be addicted to sugar?” to learn more.

 

Resources:

Spiegel, S., Leproult, R., L’Hermite-Baleriaux, M., Copinschi, G., Penev, P.D., Van Cauter, E. (2004). Leptin Levels Are Dependent on Sleep Deprivation: Relationships With Sympathovagal Balance, Carbohydrate Regulation, Cortisol, and Thyrotropin. The Journal of Clinical Endocrinology & Metabolism 89(11):5762–5771. doi: 10.1210/jc.2004-1003

Meguid, M.M., Fetissov, S.O., Varma, M., Sato, T., Zhang, L., Laviano, A., & Rossi-Fanelli, F. (2000). Hypothalamic Dopamine and Serotonin in the Regulation of Food Intake. Ingestive Behavior and Obesity. Nutrition 16:843-857. PII: S0899-9007(00)00449-4

McVay, M.A., Copeland, A.L., Newman, H.S., Geiselman, P.J. (2012). Food cravings and food cue responding across the menstrual cycle in non-eating disordered sample. Appetite 59(2):591-600. doi:10.1016/j.appet.2012.07.011

Murray, M. Vickers, Z. (2009). Consumer views of hunger and fullness. A qualitative approach. Appetite 53:174-182. doi:10.1016/j.appet.2009.06.003

Ledochowski L, Ruedl G, Taylor AH, Kopp M (2015) Acute Effects of Brisk Walking on Sugary Snack Cravings in Overweight People, Affect and Responses to a Manipulated Stress Situation and to a Sugary Snack Cue: A Crossover Study. PLoS ONE 10(3): e0119278. doi:10.1371/journal.pone.0119278

Kourouniotis S., Keast R., Riddell L.J., Lacy K., Thorpe M.G. & Cicerale S., The Importance of Taste on Dietary Choice, Behaviour and Intake in a Group of Young Adults., Appetite (2016), doi: 10.1016/j.appet.2016.03.015

Leave a Reply