科学拯救吃货：你为什么总是饿？（下）

It sounds counterintuitive, but piling your plate with more food -- lean protein and healthy fat, specifically -- keeps hunger pangs at bay. "Not only does protein stay in your stomach and promote feelings of fullness, it's been shown to have an appetite-suppressing effect," says Rumsey. Aim for at least 46 grams of protein per day (best sources: Greek yogurt, eggs, lean meat and whole grains), which is the RDA for women between 19 and 70. For men, it's 56 grams per day.

Just like protein, unsaturated fat is also linked to feelings of satiety. "When you're satisfied after a meal, you are more likely to listen to your hunger cues and not eat again until you are truly hungry," says Rumsey. Add this heart-healthy, brain-boosting kind of fat to your meals in the form of oils, nuts and seeds and avocados. Experts recommend that adults limit their fat intake to 20 to 35 percent of their total daily calories.

Yet another reason why ghosting on breakfast or forgoing other meals throughout the day backfires on you. When you skip a meal and your stomach is empty for too long, it produces an uptick in the hunger hormone ghrelin, which ramps your appetite, says Rumsey. "Ghrelin also prompts the GI tract to expect food to come. Your ghrelin levels are in overdrive, and so is your lust for food." When you finally give in, you're prone to a binge. As a general rule, try not to let more than 4 to 5 hours go by between meals. And even if you hate breakfast, eat something in the a.m. within an hour of waking, like yogurt, peanut butter and apple slices, or a soymilk smoothie.

Pinterest recipe boards. Facebook photos of your friends' lunches. Late-night TV ads for takeout pizza. With images of food saturating our lives 24-7, it's no wonder so many of us are constantly craving the real thing. The connection between what we see and what we desire has been documented by science: a 2012 study from the journal Obesityfound that just looking at food cranked up levels of ghrelin, the hunger hormone. Getting a whiff of food has a similar effect, says Moon. "Pleasant food aromas stimulate an involuntary physiological reaction: the mouth will salivate and the stomach will contract, mimicking hunger pangs," she says. Of course, you can't totally eliminate the possibility of seeing or smelling food. But try limiting your exposure, say by skipping TV commercials and un-following food brands on Instagram.

When you wolf down your meal, your stomach might be full, but you haven't allowed your brain enough time to register that fullness. When your brain is still in the dark, it keeps your appetite high... and you continue eating. A study published in 2013 in the Journal of Clinical Endocrinology & Metabolism supports this, finding that eating at a moderate pace prompts the release of hormones that tell your brain "no more." Try eating your food slowly, savoring each bite and enjoying the ritual of a good meal. Then wait at least 20 minutes before deciding if you really do need another helping. That's about how long it takes for that fullness signal to reach your brain, says Rumsey.

The same drugs you might be taking regularly to treat a health condition can also drive you to raid the refrigerator. Antidepressants such as Zoloft and Paxil, as well as corticosteroids such as prednisone (prescribed to treat potentially dangerous flareups of the immune system due to allergies, asthma, inflammatory bowel disease like Crohn's disease, and some cancers), are known to affect appetite, says Rumsey. If you're on one of these prescription and feel hungry after a normal-sized meal, talk to your doctor to see if it's possible to switch to another drug.