Rich and sugary foods trigger our innate survival instinct. Can’t kick them? You don’t have to, according to science
The first thing you need to know about food cravings? That nearly everything you know about them is wrong. Over the past several decades, well-meaning experts—and, yes, some profit-motivated diet peddlers—have told us cravings are something to be resisted at all costs. “Giving in” is not only harmful to one’s health, the story goes, it also shows a distasteful lack of willpower! The reality is quite the contrary, top researchers and dietitians report.
Food cravings are a natural part of humans’ strive to survive, says Mark L. Andermann, a neuroscientist who studies hunger and eating behavior at Harvard Medical School. “Your brain is programmed from birth to act as if there won’t be enough calories in the world,” he explains. Famine stalks countries such as Somalia and Sudan to this day. And even in the industrialized West, American colonists and European farmers were starving to death as late as the 18th century. Having evolved under a near-constant threat of undernourishment and starvation, “your brain tells you that you should eat high-calorie foods whenever possible,” says Andermann.
Fast-forward to the 21st century: Factory farming, mass food processing, and convenience culture give us access to hundreds of calories in a matter of seconds. But our “old brains haven’t caught up to this new environment,” says Andermann, and these once-helpful eating urges are backfiring. That said, we don’t need to fear cravings, says dietitian Dana Notte, who specializes in treating women with lifelong weight struggles and is the owner of ThrivInspired Nutrition in Burlington, Vt. “The more we understand cravings and examine the roots of our drive to eat, the more we can actively choose what to do with those cravings and take better care of our bodies.”
YOUR CRAVINGS BRAIN
Food cravings originate in the brain, not just your belly. Hormones, memories, sights, smells, emotions, thoughts, and signals between brain cells all influence what and how much you want to eat. For example, research shows that enticing images of food on billboards and TV trigger cravings and drive (over-)consumption, and these effects are even more pronounced when you’re hungry. Directly after a meal, these “food cues” lose much of their punch, at least in averageweight individuals, says Andermann. But people with obesity or binge-eating issues don’t experience that same steep post-meal drop-off, suggesting that brain differences may be at least partly responsible for some people’s persistent cravings.
Internal physical cues kick off cravings, too, but not in the way you may think. “Generally speaking, we don’t have much evidence to support the idea that needs for specific vitamins or minerals trigger cravings for particular foods,” says Notte. “What we do see in nutrient deficiency is the body encouraging you to go out and seek more food in general to try to fill in the gaps.” Although you’re not more likely to crave steak for the iron, cravings for sugars and carbohydrates soar when blood sugar drops, such as when you skip meals. “Carbohydrates are the body’s preferred source of energy and the easiest to break down into glucose, so your body will seek them out when you need an energy boost,” she says. Intake of carbohydrates spikes when we’re sleep deprived.
Foods high in fat, sugar, and certain other additives also cause sudden spikes in dopamine in parts of the brain related to “reward” and pleasure, explains Miguel Alonso-Alonso, director of the Laboratory of Bariatric and Nutritional Neuroscience at Beth Israel
Deaconess Medical Center in Boston. Simply put, these “hyperpalatable” foods make us feel gooood in some of the very same ways that sex and drugs do. Whether sugar or any other food is literally, diagnosably “addictive” is still a matter of debate. What’s not: Reward signals in the brain can override cues like fullness in many people, contributing to overeating, weight gain, and, sometimes, addict-like behavior around food, he says.
That said, cravings and food preferences can change over time—especially if a person begins to eat a larger variety of nutritious foods. Try to focus on what you’re adding instead of what you’re considering off-limits, says Notte. “Rather than approaching it as ‘I really need to cut out white flour,’ ask yourself what types of starches, such as whole grains and beans, you could add into your diet to bring more balance there. When we can bring more balance into our diet and meet our bodies’ overall needs, we do start to see that our cravings change.”
Giving in to every fatty, sugary food whim can cause weight gain, insulin resistance, and other negative health outcomes. But actively ignoring and suppressing cravings can backfire, leading to a restrict-andbinge cycle (otherwise known as yo-yo dieting) that contributes to some of the very same health problems. “Cutting a food out of our diets generally increases cravings for that food—thinking a food is off-limits makes us want it so much more,” says Notte. “It’s the scarcity effect. Cravings and overeating behaviors are, in part, related to perceived food scarcity and uncertainty about when it’ll be available again.” Indeed, researchers have found that when mice are deprived of food for several hours and then are given access to a sugary liquid, they binge on it—whereas animals with constant access to the sugar don’t. A similar rebound effect is seen in humans.
For most people with lifelong weight struggles, here’s how that cycle plays out: Restricting calories and food groups increases cravings for off- limits foods. After a month or three months or a year, when a person’s resolve breaks—as it nearly always does—he’s probably going to overeat those high- calorie foods, even binge. For some folks, this “rebound eating” can go on for days, weeks, or even months.
MINDFUL HABITS
For most of human history, cravings and constant food seeking helped us survive lean times. But the] modern foodscape is one of ubiquitous, cheap calories marketed to us by a $5 trillion food-retail industry. This is where the reasonable, prefrontal-cortex part of our big brains come in, says Andermann. We can tap this region to do three things: stop and notice cravings, decipher where they’re coming from, and choose how to respond. “When asked how they know when they’re finished with a meal, Americans say it’s when a TV show is over, or when their plates are empty—not when they feel full,” says Andermann. “The first step in changing any kind of learned action is mindfulness—paying attention.”
You might start by noticing what you’re doing when a hankering crops up. Habits are a powerful trigger for cravings, says Alonso-Alonso. Our brains like convenience and efficiency above all else, and “habits operate as behavioral shortcuts in daily life and are a preferred mode of making decisions with minimal effort,” he says. Shake up your routine as much as you can to create more of a pause between craving and action.
“Sometimes all you need is a moment to ask yourself if you’re truly hungry for this right now,” says Notte. You may realize that you’re tired and what you need is to turn off the TV and go to bed. Or perhaps you’re stressed, and the craving is more about soothing yourself than how yummy the food is. Folks with emotional- and binge-eating issues especially may crave certain foods as a kind of self-medication, says Andermann. Cognitive behavioral therapy (CBT) and dia lectica l behav iora l therapy (DBT) are both research-backed ways people with emotional cravings can gain more control over their eating behaviors.
Regular physical activity has also been linked to a greater ability to actively control eating behavior. Animal studies suggest it could be due to changes in blood flow, the release of certain brain chemicals such as feel-good endorphins, and better functioning of neurons, says Alonso-Alonso.
The answer to “Why am I craving this food?” may simply be that you want the pleasure of eating it. That’s OK, insists Notte. “Your ultimate goal should never be simply to not eat the food that you’re craving,” she says. Instead, the aim is to make a mindful and informed decision that balances your needs in the moment with what you want in the long term. “Food is a great pleasure,” she continues, “and humans are pleasure-seeking creatures. Sometimes just allowing ourselves to enjoy the food and then move on really is the best way to handle it.”
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