Seven ways our bodies tell us we're hungry--even when we're not.

Time of Day

Through routine, we condition our bodies to expect breakfast, lunch and dinner at the same time each day, says Randy Seeley, a professor of psychiatry at the University of Cincinnati." Part of the reason you're hungry at noon is because that's the time you've eaten for the last 100 days."

Sight

Research using MRIs shows that brain patterns of people viewing photos of foods they like and foods they don't like are "very different," Seeley says. "The body anticipates when food is about to enter the system." And that's why your mouth starts watering when you see Mom's pie.

Variety

Even after eating a large meal, we often "make room" for dessert, because a desire for sweets hasn't been satisfied. Ann Gaba, a registered dietitian at New York Presbyterian Hospital, says that sometimes all it takes is a bit of fruit in a salad during a meal to curb a sugar craving.

Smell

Scent is one of the key ways we cue our bodies that food is near. Once the trigger goes off, it can induce the insulin secretion that makes us think we're hungry. Says Sharron Dalton, a nutrition professor at New York University: "Smell and sight alone activate the appetite cascade."

Alcohol

Drinking has not been scientifically proved to stimulate appetite, but too much beer, wine or liquor can impair judgment, causing us to eat more. "Most people who are on a diet will say it's a lot harder to push themselves away from the table if they've been drinking," observes Seeley.

Temperature

The colder the temperature, the more people tend to eat, which is why restaurants often keep thermostats low. "Your metabolism drops when it's time to eat, and eating warms you up," says David Ludwig, professor of pediatrics at Harvard. "Heat is a satiety signal."

Refined Carbs

After a meal heavy in refined carbohydrates, like white pasta, the body may crave food again within only a few hours. These foods cause blood sugar to drop, and "when our blood sugar is crashing, we're going to be a lot more interested in food in general," Ludwig says.

身體以以下七種方式給我們傳達餓了的信息，即使有時我們并不餓。

時間

“按一般規律，我們的身體會在每天差不多相同的時段期待進早餐、中餐和晚餐，”辛辛那提大學精神病學教授蘭迪.西利說，“你在中午感到饑餓的部分原因是因為在過去的一百天里你差不多都在這個時間吃中飯。”

視覺效果

“使用核磁共振成像查看人們看自己喜歡或不喜歡的食品照片時的人腦模式，研究表明結果非常不同，”西利說。“當食物即將進入該系統時，身體就開始期待了。”這就是為什么當你看到媽媽做的餡餅時就開始垂涎三尺。

多樣化

即使剛吃過大餐，我們通常仍然能塞下一份甜點，因為想吃甜點的需求未被滿足。紐約長老會醫院的注冊營養師安加巴表示，有時只要在進餐期間有一點水果沙拉，就能控制我們對糖分的需求。

氣味

氣味是提示我們的身體我們跟食物很接近的一個關鍵因素。一旦觸發了這個欲望，它可以促使胰島素分泌，使我們認為自己餓了。紐約大學營養學教授莎倫.道爾頓說：“僅嗅覺和視覺就能激活我們的胃口。”

酒精

從科學的角度來講，少量飲酒的確能刺激食欲，不過過量的啤酒、紅酒、烈性酒會麻痹我們的判斷力，導致我們進食過多。“正在節食的很多人將會說如果自己正在喝酒的話就很難從餐桌邊走開。”西利說。

周圍的溫度

溫度越低，人們會傾向于吃更多的食物，這就是問什么餐廳總是把空調開得比較低。“進餐環境的溫度比較低時，人體的新陳代謝在下降，吃東西能讓你感覺暖和些。”哈佛大學兒科教授大衛.路德維希說，“燥熱是飽膩的信號。”

精制的碳水化合物

在進食大量像白面條類的精制碳水化合物后，人體可能會在幾個小時內就又想吃東西了。這些食物導致血糖下降，“當血糖降低，通常我們就會對食物比較有興趣了，”路德維希說。