Why Do I Crave Junk Food?

For many of us, there’s nothing tastier than sweets or fatty foods, full of salt and grease, and overflowing with empty calories. Removing junk food from your diet is one of the most effective steps you can take for a long, healthy life, but junk food cravings can feel uncontrollable.

Fighting the urge to gorge on junk food often leads us to do that very thing—indulging in foods that may taste good but have no nutritional benefits. There are good reasons why our brain may be telling us to put the chips down, yet our stomach says otherwise.

What’s So Bad About Junk Food?

Sadly, everything is wrong with junk food except the taste. Junk food has high levels of saturated fats, sugar, salt, or processed carbohydrates—often all of these in every bite. Junk food can be soaked in sugar, brimming with salt, or both. All junk food includes ingredients that can actively cause harm when they’re consumed regularly, while at the same time giving you no significant nutrients.

Junk food has little to nothing in the way of nutrition and contains mostly empty calories, lacking protein, fiber, vitamins, essential fatty acids, or minerals. As tasty as chips, cookies, fast food, and other snacking food taste, there’s no real benefit past instant gratification.

Junk food contributes to the development of obesity, high blood pressure, and type 2 diabetes, all while aggravating many other conditions. It might seem far-fetched, but because the typical ingredients found in junk food cause systemic inflammation, consuming junk food as part of a daily diet can make asthma and other inflammatory diseases worse.

It tastes good, it’s awful for us, and we crave it. So, why do we have junk food cravings?

What’s a Food Craving?

A food craving is an intense, often overwhelming desire to consume food that may strike out of nowhere. Nonselective food cravings drive us to eat anything we can, even things we normally wouldn’t choose. Nonselective food cravings usually arise from prolonged hunger, fasting, or low blood sugar.

Junk food cravings are broadly selective. They drive us to seek food that’s high in simple or refined carbohydrates, sugary, salty, or fatty foods, or a combination of all those elements. These cravings are distinct from the condition called pica, which refers to an overwhelming hunger for a non-food item, like chalk. Picas are often a sign the body is lacking an element of some type.

Reasons We Crave Junk Food

It’s easier to understand food cravings if we understand a little about how the body generates and controls the feeling of being hungry. Our perceptions of hunger and food cravings are controlled by two hormones: leptin and ghrelin. Three neurotransmitters are also involved in hunger and feeling full: serotonin, epinephrine, and dopamine.

• Leptin comes from stored fat cells and helps us feel full.
• Ghrelin is produced by the stomach and intestines, and its role is to cause hunger and focus us on seeking food.
• Serotonin is produced in the brain and the gut. Sometimes called the “happy drug,” it reduces feelings of anxiety and depression while simultaneously promoting feelings of calmness. It’s released in large amounts when we eat foods filled with carbohydrates. Foods that are rich in carbohydrates like sugar cause a rush of serotonin to flood through the brain, but levels of serotonin then decline once the rush ends.
• Epinephrine and dopamine are produced from high-protein foods, like meats, legumes, and dairy foods. Epinephrine leads to feeling energized, and dopamine allows us to feel pleasure. These chemicals are abruptly released by some kinds of junk food, but again, these highs crash soon afterward.
• Cortisol, the stress hormone, can also modify the levels and effectiveness of leptin and ghrelin. Its most common effect is to increase appetite.

The Top Causes of Junk Food Cravings

All the top causes of junk food cravings interact and drive each other, which can make reducing these cravings more challenging.

1. Habit. Habit is a big cause of junk food cravings. We train our bodies what to expect, which in turn shapes what we want when it’s time to eat. Regular, reflexive consumption of food that’s bad for us will lead to cravings for that same type of food. After all, once reaching for pre-packaged and highly processed food becomes our go-to way of eating, it feels normal and comforting.
2. Food euphoria. Starchy carbohydrates and sugar provoke a big release of serotonin in the brain, which causes a tsunami of good feelings. We feel calmer and less anxious after consuming these kinds of foods, because the basic building block of serotonin, tryptophan, enters the brain more easily when blood glucose pumps up insulin in the blood. Insulin clears a path for tryptophan to flood the brain, leading to a huge burst of bliss from the newly made serotonin.
   It’s true that serotonin suppresses appetite, but it can only do that after it’s produced, and by the time that happens, we’ve already eaten a lot of junk food, throwing our glucose-insulin balance out of whack.
3. Lots of salt and sugar also causes unusually large releases of dopamine, known as the “pleasure chemical,” which provides an immediate reward for consuming these kinds of foods, which again reinforces habitually eating junk foods.
4. Not getting enough sleep. As little as one night of poor sleep can throw ghrelin and leptin production off-kilter, causing a rise in ghrelin and a decrease in leptin, leading to an increase in hunger as appetite-suppressing hormones drop.
5. Stress. Both acute and chronic stress can aggravate food cravings by causing cortisol to stay active in the body. As cortisol can cause intense food cravings, stress is a primary cause of junk food cravings.
6. Depression and/or anxiety. Any disorder that affects the production or effectiveness of serotonin or dopamine can also interfere with our eating habits.

Junk food cravings can be stopped, although it’s not an immediate process. Taking an inventory of your eating and sleeping habits is a great first step toward eliminating food cravings. If you want help in loosing weight, our health coach can help.

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