Ridiculously large portions aside, why you overeat is anything but obvious.

Most of the culprits behind your overeating quietly hum along each and every day in the background, masquerading as a lack of willpower, gluttony or just a hollow leg that desperately needs filling.

To prove our point — and help keep you from overeating, gaining weight and overeating some more — here are seven of the most surprising foods, habits and diets that can turn any person into an eating machine.

1. Artificial Sweeteners

Besides making your food and drink taste worthy of overeating, they interfere with your body’s ability to gauge how much you should be eating, per research from Purdue University. According to researchers, since artificial sweeteners are crazy sweet (did you know they range from 200 to 7,000 times sweeter than table sugar?) but contain zero calories, over time, they weaken your body’s ability to count calories according to a food’s sweetness. That means your body has a harder and harder time knowing when it should feel full — and when you should stop eating.

2. Super Strict Diets

Aren’t strict diets supposed to prevent you from overeating? Well, in theory. In practice, however, they are a huge trigger for overeating, says family medicine physician Michelle May, founder of “Am I Hungry?” mindful-eating programs and author of “Eat What You Love, Love What You Eat.” “Extremely low-calorie diets set in motion a pattern of biological and psychological hunger and cravings,” she says. “The human body registers food and calorie restriction as starvation, so when you follow a strict diet, your brain pumps out signals telling you to seek out not just food, but extra food in case you suffer from starvation again. It used to be that if we didn’t listen to these signals, we’d die.” Now, those signals just make you binge, feel lousy and binge again.

3. Healthy Food Swaps

“People don’t realize that satiety isn’t just your stomach being full,” May says. “It also incorporates your desire for certain flavors and textures.” So when you go into the kitchen wanting potato chips and leave with an apple, you’re likely going to end up heading back for a bowl of cereal … then a slice of cheese … then a granola bar, until you finally “give in” and eat the chips. “You keep eating, wanting to feel satisfied, but until you get to enjoy the taste and texture you were craving, you aren’t going to feel satisfied,” she says. That’s not to say subbing out unhealthy foods for healthy ones is a bad idea. But the closer your replacement tastes and feels to the one you’re craving (think: kale chips over potato chips), the more likely it is to get the job done.

4. Out-of-Whack Hormones

And that’s not just when it comes to a woman’s time of the month. In a 2015 Cell Reports study, Rutgers University researchers found that deficiencies in the hormone glucagon-like peptide-1 (also known as GLP-1) may cause people to eat more, especially high-fat foods. That’s because the hormone helps regulate the brain’s reward system, and deficiencies can turn your stomach into a bottomless pit. The U.S. Food and Drug Administration recently approved a GLP-1-mimicking drug, called Saxenda, as a treatment for obesity. While it’s not right for everyone, it is proof that whether or not you overeat is about more than willpower.

5. Poor Sleep

In one Mayo Clinic study, people who were robbed of about 80 minutes of sleep ate an average of 549 extra calories the next day. That may be because a lack of sleep lowers your levels of the feel-full hormone leptin while increasing levels of the hunger-driving hormone ghrelin, explains registered dietitian Georgie Fear, author of “Lean Habits for Lifelong Weight Loss.” What’s more, when you’re groggy and tired, who has the energy to think about portion sizes?

6. Exercise

When done right, your workout routine can go a long way toward regulating your body’s hunger signals and helping you eat healthier. However, when people think exercise “earns” them second and third portions, overeating is just about guaranteed, says exercise scientist David Chesworth, a fitness specialist and trainer with Hilton Head Health’s weight-loss center in South Carolina. After all, that 400-calorie ice cream cone will take a full hour in the gym to burn off. And most people tend to grossly overestimate how many calories they burn during a workout. It doesn’t help that, according to research from the University of California–San Francisco, treadmills overestimate calorie expenditures by 13 percent, and elliptical machines by a whopping 42 percent.

7. Low-Fat Foods

According to research from the Cornell University Food and Brand Lab, most people assume that low-fat foods such as ice cream and cookies contain about 40 percent fewer calories than their full-fat counterparts — and wind up eating almost twice as much food as they would if they went for the original. Little do they know that those foods actually contain only 11 percent fewer calories on average. Plus, compared to their full-fat versions, low-fat processed foods are often higher in sugar and sodium, two ingredients that can trigger overeating all on their own, Fear says.

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7 Surprising Things That Make You Overeat originally appeared on usnews.com