Fiber has no magical fat-burning properties. It simply helps you feel full without adding a lot of extra calories to your diet. When you have a baked potato (with skin) instead of a bag of potato chips, for example, you’re not only eating fewer calories — you’re less likely to feel hungry again an hour later.
“It’s choosing the most intelligent calories,” says Rebecca Blake, director of clinical nutrition at Mount Sinai Beth Israel in New York City.
How exactly does fiber guard against hunger pangs? Simple: It fills your stomach, stimulating receptors that tell your brain that it’s time to stop eating.
You’ll also need to drink plenty of H20, about eight glasses a day, to move fiber through your digestive system, and that helps against hunger too. “All that water contributes to feelings of fullness and controls thirst, which can often be confused with hunger,” says Stephanie Polizzi, a registered dietitian nutritionist.
The “soluble” type of fiber, which absorbs water, forms a kind of gel inside your gut, slowing the absorption of sugars into your bloodstream. Lower blood sugar levels mean lower insulin levels — and that means your body is less likely to store fat.
It’s best to get your fill of fiber from food rather than from supplements. But supplements might help if you can’t get enough fiber from your diet, and especially if you’re feeling constipated. Talk to your doctor about what’s right for you.