The Science of Hunger: How to Control It and Fight Cravings

Whether you’re trying to lose weight, maintain weight loss or just stay healthy, at some point, you’re going to get hungry. But simply eating whenever the urge strikes isn’t always the healthiest response — and that’s because hunger isn’t as straightforward as you may think.

A complex web of signals throughout the brain and body drives how and when we feel hungry. And even the question of why we feel hungry is not always simple to answer. The drive to eat comes not only from the body’s need for energy, but also a variety of cues in our environment and a pursuit of pleasure.

To help you better understand and control your hunger, Live Science talked to the researchers who have looked at hunger every which way, from the molecular signals that drive it to the psychology of cravings. Indeed, we dug into the studies that have poked and prodded hungry people to find out exactly what’s going on within their bodies. We found that fighting off that hungry feeling goes beyond eating filling foods (though those certainly help!). It also involves understanding your cravings and how to fight them, and how other lifestyle choices — such as sleep, exercise and stress — play a role in how the body experiences hunger.

Here is what we found about the science of hunger and how to fight it.

Jump to section:

  • What is hunger? Homeostatic vs. hedonic
  • Controlling hunger in the short term – cravings
  • Controlling hunger in the long term
  • What about “hunger blocking” supplements?

What is hunger? Homeostatic vs. hedonic

Before we begin, it’s important to understand exactly what hunger is — what’s going on inside your brain and body that makes you say, “I’m hungry”?

As it turns out, feeling hungry can mean at least two things, and they are pretty different, said Michael Lowe, a professor of psychology at Drexel University in Philadelphia.

Of course, there’s the traditional concept of hunger: when you haven’t eaten in several hours, your stomach is starting to grumble and you’re feeling those usual bodily sensations associated with hunger, Lowe said. This feeling of hunger stems from your body’s need for calories; the need for energy prompts the signal that it’s time to eat, he said.

Researchers refer to this type of hunger as “homeostatic hunger,” Lowe told Live Science.

Homeostatic hunger is driven by a complex series of signals throughout the body and brain that tell us we need food for fuel, said Dr. Amy Rothberg, director of the Weight Management Clinic and an assistant professor of internal medicine in the University of Michigan Health System’s Division of Metabolism, Endocrinology and Diabetes.

Hormones in the body signal when energy stores are running low. When this occurs, levels of ghrelin (sometimes referred to as the “hunger hormone”) start to rise, but then become suppressed as soon as a person starts eating, Rothberg said. In addition, as food travels through the body, a series of satiety responses (which signal fullness) are fired off, starting in the mouth and continuing down through the stomach and the small intestine, she said. These signals tell the brain, “Hey, we’re getting food down here!”

And up in the brain, another series of signals is at work, Rothberg said. These are the sets of opposing signals: the hunger-stimulating (“orexigenic”) peptides, and the hunger-suppressing (“anorexigenic”) peptides, she said. These peptides are hormones that are responsible for telling the brain that a person needs to eat or that a person feels full.

Unsurprisingly, the best way to get rid of homeostatic hunger is to eat. And your best bet to maintain that full feeling for a healthy amount of time is to eat nutritious foods that, well, fill you up, Rothberg told Live Science. [Diet and Weight Loss: The Best Ways to Eat]

A diet that contains fiber and lean protein is very filling, Rothberg said. And protein is the most filling of the macronutrients, she said. Indeed, a recent meta-analysis study in the Journal of the Academy of Nutrition and Dietetics concluded that eating larger amounts of protein does increase feelings of fullness compared to eating smaller amounts of protein. [Which Types of Foods Are The Most Filling?]

But it’s also important to be careful about certain foods. Zero-calorie sweeteners, for example, can confuse fullness signals and trick your brain into thinking you haven’t eaten much when you actually have, thus leading you to eat more, Rothberg said. (There is much debate among health experts about the effects of these sweeteners in the body. For example, although they may help people control their blood sugar levels, evidence is mixed on whether they help people lower their calorie intake or lose weight. In our interview with her, Rothberg was referring specifically to how zero-calorie sweeteners may impact feelings of hunger and fullness.)

Another food group to be careful about is ultraprocessed foods, which are loaded with fat and sugar. People don’t just eat for calories, they eat for pleasure, but foods like these can drive the brain to want more of them, essentially overpowering the normal fullness signals firing in the brain, Rothberg said.(Ultraprocessed foods are those that, in addition to sugar, salt, oils and fats, include additives like emulsifiers, flavors and colors — think potato chips or frozen pizza.)