As for when to snack, Spangle advises a mix of going by the clock and listening to your body. "If it's mid-morning and you're hungry, you probably need a snack. If it's 11 or 12, eat lunch," she says. And plan ahead so you're not caught short, particularly in the crucial late afternoon. Douglass actually advises skipping a before-bedtime snack, since people tend to pig out at night and there's no activity in the next eight to 10 hours to burn off the extra calories. "If you need something after dinner, have a glass of milk or a little carton of yogurt," she says. And whenever you get the urge to nibble, ask yourself whether you really need to, says Spangle. "Are you hungry, or is this a desire to eat? Do you just not want to go to bed? Is snacking just going to fill up the time? What else could you do besides snacking?"
If you don't like snacking or it doesn't work in your eating plan, you don't have to do it. (Unless, that is, you have diabetes or some other condition, and your physician has advised frequent meals.) Studies suggest the most important factor is not when you eat but rather the amount of food you take in—and research in both animals and humans shows that eating less is associated with better health. "If there's a reduction in overall caloric intake, you're going to lose weight," says Mattson. "My view... is that it doesn't make a heck of a lot of difference how frequently you eat."
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