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.