Chewing gum or anything else tricks your stomach into thinking food is coming, which turns off hunger signals.

Meals with enough or lots of protein make two key hunger hormones (CCK and ghrelin) stay active longer in both lean and obese men, which might help them feel full longer.

Even though hunger and fullness hormones are different in older women, those differences don’t match up with who eats less—so the problem probably isn’t the hormones themselves.