Hunger is a signal that reminds us to eat. This built-in, biological cue ensures our survival.
A food craving, however, is a cry for comfort. It comes in the form of cookie dough ice cream, cheese fries, a cola, or some other intensely flavored concoction.
Hunger is subtle and can be satisfied by a wide range of foods. But a craving nags at us until we feed it something specific. Cravings can become so powerful that they can cloud your judgment and override your willpower.
Worst of all, the foods we typically crave aren’t in our best interest. Overwhelming evidence shows that the sweets, sodas, and snacks so many of us have grown to love are a major contributor to the chronic health problems that plague the modern world: obesity, sleep apnea, diabetes, heart disease, cancer and more.
But if we’re built to survive, why don’t we only seek well-balanced meals? Why are we compelled to eat things we know rationally are not good for us?
Eating for Dopamine
According to Elena Zinkov, a naturopathic doctor based in Bellevue, Washington, it’s because we often use foods to chase a desired emotional state rather than to satisfy an empty stomach.
“This habit gives you about 10 seconds of pleasure, but it really starts to be destructive in the long-term,” she said.
Zinkov’s new book, Crave Reset, unravels the psychology and physiology behind cravings and offers strategies to help us kick our junk food obsession for good.
When we’re suddenly struck by a food craving, it can feel beyond our control to ignore. Yet, we are also responsible for cultivating our cravings over time. This is why stopping a craving is so difficult. It’s because our brain and body become dependent on these foods, and begin to feel off without them.
Consider the brain chemicals that control our sensation of pleasure: serotonin and dopamine. Serotonin surges when we taste something good, and dopamine solidifies the behavior, ensuring that we’ll seek that food again when we’re looking for something to eat in the future.
These chemical signatures have guided our ancestors’ food preferences and meal satisfaction since forever. But this system backfires in the modern food environment, where calories are plentiful, sugar is cheap, and products are meticulously engineered to be irresistible.
“For our ancestors, food wasn’t readily available. It would either be a time of feast, or famine,” Zinkov said. “Nowadays, you drive around the corner and there’s a 7-Eleven, and there are so many options. In this environment, we’ve grown out of sync with our hunger cues.”
Diminishing Returns of Emotional Eating
Constant consumption of intensely crave-able foods—those high in fat, sugar, and salt—have been linked with a reduction in D2 dopamine receptors. Scientists have discovered that people who experience food addiction and weight gain due to compulsive eating have fewer D2 receptors. As a result, they need extra stimulation to experience a sufficient level of satisfaction.
In optimal amounts, dopamine is stimulating, energizing, and motivating. With sufficient dopamine, you feel focused, motivated, and happy. Low levels result in low energy, depression, and a lack of interest. This means that as we rely more on our cravings to fuel our sense of satisfaction, it begins to distort our sense of well-being.
“This is why I say cravings relate to something bigger,” Zinkov said. “When we have a craving, we’re usually trying to distract ourselves from something. People usually have the most cravings during times of stress, painful experiences, or they’re bored—they’ll eat because they have nothing else to do.”
When cravings become our go-to method of dopamine secretion, we condition ourselves to need a regular hit of our favorite flavors just to make it through the day. Do you feel sad and tired when you restrict your sweets? It’s not due to your body’s needs for sugar. You’re just chasing the rush it delivers.
Caffeine influences our neural chemistry in a similar way, binding to proteins in the brain called adenosine receptors. Used in moderation, this can help us stay focused. But if we rely on this trick too heavily, we create a vicious cycle. With our second cup of coffee, our body begins to build a tolerance to caffeine, and our brain creates more adenosine receptors. Over time, we need more caffeine to maintain the same level of energy.
Feeding a Malicious Microbiome
Food cravings are not just in your head. A lot of it lies in your gut.
Inside each of us is an enormous colony of beneficial bacteria collectively known as our microbiome. The bulk of our microbiome—about three to five pounds worth—inhabits our large intestine. The composition of this colon colony has been linked to our mental health, mood, digestion, hormonal balance, weight, gene expression, and general wellbeing, as well as the food we crave.
Our microbiome consists of hundreds of different strains of bacteria, and what we eat plays a huge role in which strains proliferate. Some thrive on fiber. Others prefer specific fats.
There are general similarities in the human microbiome, but diet contributes much of the differences. For example, bacteria that digest seaweed have been identified in people from Japan, while African children raised on sorghum have been found to have a unique microbiome that helps digest the cellulose from this grain.
As bacterial strains vie for dominance in our gut, the best-fed strains always come out on top. According to Zinkov, we dictate the dominant bacterial strains by voting with our forks. However, the candidates we choose may have an agenda directly at odds with our well-being. They strengthen our craving for more sweets, despite the detrimental impact this has on our own health.
“We have billions of cells in our body, but we have even more gut bacteria, and we are hosting a party for them,” Zinkov said. “They are predominantly concerned about themselves, not necessarily us.”
As the number of junk-food loving bacteria grow in your gut, they churn out hormones and neurotransmitters that further fuel the fire, resulting in more health problems, and more biological conditions that strengthen your cravings even more.
This is what our willpower is up against—not just our own desires, but the desires of the bacterial colony we’ve cultivated. Research published in a 2014 edition of BioEssays explains that our struggle to resist cravings high in sugar and fat may be hard, because we face an enemy within created as a result of our poor past choices.
“The resistance to change is frequently framed as a matter of ‘self-control,’ and it has been suggested that multiple ‘selves’ or cognitive modules exist each vying for control over our eating behavior,” states the article. “Here, we suggest another possibility: that evolutionary conflict between host and microbes in the gut leads microbes to divergent interests over host eating behavior.”
Influence of Hormones
Insufficient hormonal levels can also contribute to strong cravings. Low thyroid function, for example, decreases the rate of glucose (sugar) our cells are able to absorb. This slows the insulin response to glucose in the bloodstream following a meal, as well as the clearance of insulin from the blood after its done its job.
When metabolism slows down to such an extent, you’re bound to crave sweets just to feel a sense of equilibrium.
When cells don’t get enough glucose, this puts pressure on the adrenal glands. In response, the adrenals release a stress hormone called cortisol in order to increase the amount of glucose available to cells. This means that unless you improve thyroid function, your body will be in a vicious cycle of low blood sugar, high cortisol secretion, and higher stress levels that further suppress thyroid function.
As this cycle pushes your thyroid and adrenals to exhaustion, it sets off an array of physical, mental, and emotional symptoms, including even more severe food cravings.
Cures for Cravings
Zinkov offers many recommendations for taming our desire for bad food, but they all boil down to two things: awareness and mindfulness.
“For me, it’s about getting in that gap between the stimuli and your reaction,” she said. “When somebody has a craving that is overwhelming, it is so important to recognize it and get in that gap. That’s where growth and change happens.”
The first step is becoming aware of your hunger. If you skip meals or try to make it all day on a small salad or a single muffin, it lowers your blood sugar and weakens your will, making you even more vulnerable to a craving later in the day.
Instead, honor your body’s nutrient needs. Zinkov urges cravers to make sure they get enough protein, fiber, and healthy fat with every meal. These essential macronutrients support the systems that have been turned against us as a result of years of giving in to chronic cravings. Protein and healthy fats support brain health, and fiber helps cultivate a healthy mix of gut bacteria. Fiber also binds and removes toxins from our body, and helps keep you feeling full and satisfied, so you don’t reach for a cookie after a meal.
Nothing stokes our cravings like stress, and many of us turn to sweet treats and salty snacks for comfort. Since cravings have such a strong emotional component, it’s important to find other ways to manage our stress so that we don’t always turn junk food to soothe our nerves.
One of the most effective and accessible strategies for managing emotions is movement. Multiple studies have shown that exercise, when combined with other therapies, such as meditation and cognitive behavior therapies, can help decrease symptoms of depression, anxiety, and addiction.
To lower your stress hormones, at least 20 to 30 minutes of exercise a day is ideal. But if you’re just starting out, don’t set the bar too high. When you find yourself under stress, just going for a short walk can change how you feel.
Another important eating tip: learn to make your own healthy snacks. Using nutritious ingredients to satisfy our cravings for something sweet, salty, or crunchy makes it easier to avoid the intensely flavored but nutrient-poor junk we obsess over.
“When we make our own snacks that are rich in flavor but also rich in nutrients, not only are we changing the neurochemistry and hormone balance in our body, but we’re also changing our behavior and habits,” Zinkov said.
For Anastasia Sharova, founder of the online health-conscious cooking school, Happy Bellyfish, her most intense craving since childhood was gummi bears. Her solution to breaking the gummi bear habit was to create a healthier version at home that resembled the chewy texture and the fruity flavor of her favorite treat.
“I started eating them to satisfy my craving in a healthier way,” Sharova said. “With time, my taste perception changed and the craving slowly went away.”
Finally, be patient. If you’ve struggled with cravings for years, don’t expect to kick them in a week. Addictive behaviors can take time to unwind.
Zinkov recalls her own struggle with cravings: from realizing that her love of sugar was triggering her acne and irritability to recognizing that she was impulsively drawn to starchy snacks during stressful moments in her life. But even as she gained more understanding, sometimes she could say “no” to cheesecake, and other times she couldn’t.
“Then, I went a decade without it. I had done so much work to unwind those pathways and rebuild myself from within,” she said. “It was so liberating to feel like I was in control.”