That's when the bargaining begins: I'll have just a bite and freeze the rest. Or maybe I'll eat half of it—I've been good today—no, all of it, but I'll skip dinner tonight...
Cravings. Research is only just beginning to shed light on why so many of us succumb to them. Although scientists are still piecing together the puzzle of what exactly happens when you're in the throes of a craving, this much they know for sure: Every craving begins with a cue. The cue for a sticky bun may be something as simple as getting a whiff of its buttery aroma as you walk past your favorite bakery, or catching a glimpse of a TV commercial featuring one.
"Any cue that's repeatedly associated with high-fat and/or sugary foods can trigger a craving," explains Ashley Gearhardt, PhD, a psychologist and food addiction expert at the Rudd Center for Food Policy and Obesity at Yale University.
In other words, if you like to celebrate the end of a workweek with margaritas and Tex-Mex, eventually a craving for those things will automatically kick in every Friday afternoon. If you grew up equating, even subconsciously, your mother's homemade chocolate layer cake with comfort, you'll likely crave some version of that whenever you have a bad day.
The cue activates your brain's pleasure center, causing it to release dopamine, a neurotransmitter that pushes you to seek out the very thing you're lusting after, explains Gearhardt. Over time, this feel-good experience rewires the brain so that you're more likely to crave the food again in the future.
What's more, when you're in full-on craving mode, your brain convinces you that you are famished, making the food more difficult to resist. "Your brain starts pumping out the hunger hormone ghrelin, and your insulin levels drop, making you even hungrier than usual," Gearhardt says. As a result, it's very difficult to satisfy the craving with just a taste.
It almost seems unfair that cravings can increase feelings of hunger. You assume you'll satisfy a longing for sticky buns by eating one, but research suggests just the opposite will happen: Instead of paying attention to the physical cues of hunger and fullness, you're driven by the rush of dopamine that's telling you to find and scarf down a sticky bun (now!). And then another.
This also helps explain why you may be powerless in the presence of a dessert tray—even if you polished off a steak, two sides, and a roll only moments before. "The dessert tray, as well as the spoons and forks that are put in front of you, are all cues that you should eat," says Mark Gold, MD, chairman of the department of psychiatry at the University of Florida and a specialist in addiction medicine research.
It doesn't help that the dopamine signal occurs immediately when you come up against a cue, while the satiety signals—those telling you to stop eating—are much slower, taking 12 or more minutes after you eat to kick in. "Your brain can always find more room for food, and for a while after eating, so can your stomach," adds Dr. Gold.
Your brain on brownies
Believe it or not, cravings originally served a useful purpose, namely to keep our loincloth-clad ancestors alive. "They had powerful urges for energy-dense foods and were driven to get their hands on them in order to survive and reproduce," says Eric Stice, PhD, a senior scientist at the Oregon Research Institute.
Of course, our predecessors didn't face high-cal temptations at every turn. Today, we're bombarded by food cues (we view, on average, 7,000-plus food and beverage ads on TV per year). And we don't need to put our lives on the line every time a craving strikes. We just open our pantry, hit up the office vending machine, or take a lap around our favorite drive-thru.
It's not just that these high-fat, sugar-filled, sodium-laden foods are convenient—it's that they're actually engineered to make us crave them. "These foods have an effect on the brain that's much stronger than those produced by foods that you could hunt or grow," Dr. Gold says. "Eating fast food french fries, for instance, yields a greater dopamine release than if you were to eat a tomato picked fresh from your garden."
The complexity of tastes, flavors, and textures in processed foods is simply more stimulating for the brain than something that comes from the earth, he explains. Plus, you get a hit of dopamine each time you try a different flavor—making you crave not just one, but a variety of treats so you'll get that feel-good experience again.
Born to love chips
That explains part of the puzzle, but not all of it. New research suggests that your food preferences—and thus your cravings—may be formed not just in childhood, but in utero. "One theory is that pregnant women begin teaching their children what's safe and good to eat while they're still in the womb," says Annie Murphy Paul, author of Origins: How the Nine Months Before Birth Shape the Rest of Our Lives. So if your mom ate lots of potato chips and cheesy fries, you may be programmed to crave the same kinds of fatty, salty foods.
What's more, if you equate certain foods with feel-good moments from your childhood, you're likely to turn to them for an emotional pick-me-up. That's because often it's not the foods that we crave as much as the emotions we associate with them. In other words, it isn't just your mom's chocolate cake you're wanting, but the warm feeling you had whenever she gave you a slice.
"Pairing foods with particular feelings or situations can imprint an association between an experience and a food," explains Michelle May, MD, author of Eat What You Love, Love What You Eat. "What you might really want is to feel safe or to remember a time in your life when things were simpler."
Emotional cravings tend to sneak up on us since we're often not aware of the correlation between what we're eating and what we're feeling. For instance, if you experience a longing for a glass of wine and a bowl of pasta in the middle of a hectic workday, you may not realize or even care that what you really want is to feel relaxed and carefree—the way you do on a girls' night out at your favorite Italian bistro.
If you can identify the emotions behind the craving, you can try to find ways to fulfill those needs that are more productive than sinking your teeth into a 500-calorie sugar bomb. For instance, you might send an email to schedule a meeting with your boss to discuss your workload and the unrealistic deadlines you've been given.
"If that seems impossible, then maybe what you really need is a vacation to look forward to in order to make the work more bearable," Dr. May says. "In some small way, take steps toward meeting that need, such as making a list of the top 10 places you'd like to visit, putting in a request for time off, or taking 15 minutes to browse websites of locations you want to travel to. Even closing your eyes and taking a mini beach vacation in your mind while you breathe deeply can help short-circuit the emotions—and the craving."
A smart strategy
No matter the source of your craving (whether it began with an environmental cue or an emotional need) there's another tactic that helps derail the chemical cascade: Focus on your short- and long-term health goals.
In a recent study published in the journal Proceedings of the National Academy of Sciences, researchers examined participants' brains in an MRI scan during a craving and found that paying attention to a goal, such as getting in shape, activates the prefrontal cortex—a part of the brain that can inhibit the reward region.
The technique provides a one-two punch. In addition to dulling the craving, it also increases your ability to resist temptation. It may even keep you from rationalizing or bargaining with yourself.
Here's how to make it work for you: Write down a detailed list of health goals you'd like to achieve. If you're trying to slim down, list your current weight and how much you want to lose. "Being specific is crucial because it offers you more details that help you to say 'no,' " Dr. Gold says.
For instance, when you know you need to cut 500 calories a day in order to lose a pound a week, and that eating an ice cream sundae will prevent that from happening, you're already engaging the prefrontal cortex and dampening the dopamine release. As soon as a craving strikes, think back to those numbers in order to fight off the urge to give in to that sundae.
Also important: Jot down everything you eat throughout the day in a food journal—especially if you're trying to lose weight. Often when we're motivated to eat by cravings, we tend to inhale the food and quickly forget about it, adds Dr. Gold.
Knowing that you'll have to come back to that food journal may reduce your desire to eat it in the first place. "With practice, your ability to resist temptation becomes stronger over time—like a muscle," Gearhardt says. Your prefrontal cortex will kick in more quickly to disrupt the dopamine release and, of course, your craving. Sweet.