王一諾

Hunger is complicated and can have many different triggers，said Dr. Monique Tello，a clinical instructor at Harvard Medical School，practicing physician and director of research and academic affairs for the healthy lifestyle program at Massachusetts General Hospital.

Medical reasons：

First，it's important to rule out any medical issues. Anybody who is feeling very hungry all of the time and isn't able to gain weight or is losing weight should see a doctor，Tello said.

Conditions that could cause constant or excessive hunger，also called polyphagia，include：

Hyperthyroidism：When the thyroid is overactive，a person's body and metabolism are “all revved up”，Tello noted. Besides being hungry，patients feel jittery，shaky and their heart may be racing.

Diabetes：People with type I diabetes lose the ability to make insulin so their body can't process sugar. “They' re usually telling me：I'm eating and eating，I'm losing weight and I feel terrible，”Tello said.

Damage to the hypothalamus：This part of the brain helps regulate feelings of appetite and satiety. If it's damaged because of a tumor or head trauma，it can cause uncontrollable hunger and hypothalamic obesity.

Psychological reasons：

If there isn't an underlying medical issue，the problem could be in the head.

It's reasonable to be hungry every three to five hours given how the human digestive system works. But ever-present food marketing on TV and the constant stream of “food porn” on social media can trigger people to eat often and a lot.

哈佛醫(yī)學院臨床講師、執(zhí)業(yè)醫(yī)師、馬薩諸塞州總醫(yī)院健康生活方式項目研究和學術事務主任莫妮克·泰洛博士說，饑餓感的產(chǎn)生很復雜，可能有許多不同的誘因。

健康因素：

首先，排除健康問題，這點很重要。泰洛說，如果一直感到非常饑餓，體重未增加或正在減輕，就應該去看醫(yī)生。

可能導致持續(xù)或過度饑餓的情況（也稱為多食癥）包括：

甲狀腺功能亢進癥：泰洛指出，當甲狀腺過度活躍時，人體新陳代謝“加速”。除了饑餓，患者還會感到焦慮、顫抖，心跳可能會加快。

糖尿病：I型糖尿病患者缺乏合成胰島素的能力，因此身體無法分解糖分。泰洛表示，“很多患者告訴我，他們不停地吃東西，但是體重卻在下降，感覺很糟糕”。

下丘腦損傷：下丘腦幫助調(diào)節(jié)食欲和產(chǎn)生飽腹感。如果下丘腦因腫瘤或頭部創(chuàng)傷而受損，可能會導致無法控制的饑餓感和下丘腦性肥胖。

心理因素：

如果沒有生理問題，那么問題可能出在心理上。

考慮到人體消化系統(tǒng)的工作機制，每三到五個小時餓一次是合理的。但電視上不斷出現(xiàn)的食品廣告和社交媒體上的美食誘惑會促使人們經(jīng)常大快朵頤。

There are also deeply ingrained cultural triggers，like the idea of eating three meals a day plus snacks，Tello said. She hates the “myth of breakfast”—or the notion people have to eat as soon as they wake up.

“I tell patients，‘The more you eat，the more you want to eat，’”Tello said.

“The more people eat，the larger the stomach gets. The stomach can stretch to accommodate large amounts of food —it's a distensible organ. Then if it's empty，it signals hunger. Well，if you've got a huge stomach from eating so much so often，the minute your stomach is empty，it's signaling you to eat and you're going to eat more.”

A person's state of mind can play a role，too. Stress can increase levels of ghrelin，research has shown，and being sleep deprived is associated with higher levels of the hunger hormone.

Boredom，anxiety and depression can also send people looking into the refrigerator when they're not truly hungry.

Lifestyle reasons：

Sometimes the best answer to the question “Why am I always hungry？”is the simplest one：You're eating too little，exercising too much，or both.

Solutions：

Don't make yourself hungrier than you need to be：Limit your exposure to TV and social media. Try to watch your favorite shows without being exposed to advertising，Tello said.

Get honest：Ask yourself，“Am I really hungry？ Or am I bored？”Remove yourself from any food temptations if it's the latter.

Consider intermittent fasting：It can reconnect you with true，biological hunger;make it easier to recognize feeling full.

Feel fuller by adjusting the quality of your diet：Avoid processed carbohydrates and sugars found in foods like white bread，baked goods and cereal. Aim for a satiating diet higher in fiber，protein and healthy fats，Tello advised. Such choices will keep you more satisfied，longer.

Watch your alcohol intake：Alcohol lowers a person's inhibitions and self-discipline，which can make you eat more.

泰洛說，還有根深蒂固的文化誘因，比如一日三餐加零食的觀點。她討厭“神化早餐的重要性”——或者一起床就必須吃東西的觀念。

泰洛說：“我告訴病人，‘你吃得越多，你就越想吃’。”

“人吃得越多，胃就越大。胃可以擴張以容納大量的食物——這是一個可膨脹的器官。如果胃是空的，就會釋放饑餓信號。如果你經(jīng)常吃得太多，胃就會變大，那么你的胃一空，它就提醒你要吃東西，你會吃得更多?！?/p>

心態(tài)也會起作用。研究表明，壓力會增加饑餓激素的水平，睡眠不足與饑餓激素水平升高有關。

無聊、焦慮和抑郁也會讓人在不太餓的時候想吃東西。

生活方式因素：

有時候，對于“為什么我總是餓著肚子”這個問題，最簡單的最佳答案是：你吃得太少，運動太多，或者兩者兼而有之。

解決對策：

不要讓自己產(chǎn)生沒有必要的饑餓感：少看電視和社交媒體上的美食。泰洛說，試著跳過廣告觀看你最喜歡的節(jié)目。

老實說：問問自己，“我真的餓了嗎？還是我很無聊？”如果你只無聊得想吃東西，那就要遠離食物的誘惑。

考慮間歇性禁食：這樣可以讓你重拾真實的生理饑餓感;更容易識別飽腹感。

通過調(diào)整飲食質(zhì)量讓自己更飽：避免白面包、烘焙食品和谷類食品中的精制碳水和糖。泰洛建議，飲食應以富含纖維、蛋白質(zhì)和健康脂肪的飽腹飲食為主。這樣的選擇會讓你更容易產(chǎn)生飽腹感，餓得更慢。

注意酒精攝入量：酒精會降低一個人的抑制力和自律性，這會讓你吃得更多。