研究：吃糖過(guò)多會(huì)引發(fā)抑郁

According to new research, too much sugar doesn't just lead to weight gain, but also depression, anxiety and stress.

糖吃起來(lái)或許很甜——但是它對(duì)身體的影響卻與甜相去甚遠(yuǎn)。新研究表明，過(guò)量的糖分不僅導(dǎo)致體重的增長(zhǎng)，也會(huì)導(dǎo)致抑郁、焦慮和壓力。

Eating a diet high in fructose as a teenager makes depression and anxiety worse, scientists found.

科學(xué)家發(fā)現(xiàn)，青少年攝入高糖分食物會(huì)加重抑郁和焦慮情緒。

It also alters how the brain response to stress, they said.

他們說(shuō)，過(guò)高的糖攝入也會(huì)改變大腦對(duì)壓力的應(yīng)對(duì)方式。

Fructose is a sugar found naturally in fruits and vegetables but is also added to processed foods and drinks - from biscuits to ice cream.

水果和蔬菜中富含天然果糖，但加工食品和飲品中，比如餅干和冰淇淋，都會(huì)添加果糖。

Scientists have found fructose appears to be linked to serious modern epidemics such as cancers, heart disease, hypertension, kidney damage, type 2 diabetes and even dementia.

他們發(fā)現(xiàn)果糖似乎與癌癥、心臟病、高血壓、腎功能損傷、2型糖尿病甚至是老年癡呆癥有關(guān)。

But now researchers say it also stimulates pathways in the brain that affect how it responds to stress, which have important effects for behaviour.

然而，目前研究人員稱(chēng)果糖對(duì)大腦中的神經(jīng)通路也有刺激作用。這些神經(jīng)通路會(huì)影響大腦對(duì)壓力的應(yīng)對(duì)，從而對(duì)人的行為具有重大影響。

It can worsen the symptoms related to depression and anxiety, they said.

研究人員說(shuō)果糖會(huì)加重與抑郁和焦慮相關(guān)的癥狀。

These effects are particularly concerning during the teenage years, when a person’s stress response develops.

青春期正是壓力應(yīng)對(duì)能力發(fā)展階段，這些危害對(duì)青少年的影響尤為令人擔(dān)心。

If the body’s stress response becomes too sensitive, teenagers risk growing up susceptible to high levels of stress.

如果機(jī)體對(duì)于壓力的反應(yīng)過(guò)于敏感，青少年面臨著成年后面對(duì)高壓更為脆弱的風(fēng)險(xiǎn)。

Prolonged exposure to stress can raise blood pressure, suppress the immune system, increase the risk of heart attack and stroke, contribute to infertility, and speed up the aging process.

長(zhǎng)期處于壓力狀態(tài)會(huì)導(dǎo)致血壓升高、免疫力下降，增加心臟病和中風(fēng)風(fēng)險(xiǎn)，導(dǎo)致不孕不育，加速衰老過(guò)程。

As part of the study, lead author Constance Harrell of Emory University in Atlanta, US, and her team gave teenage and adult rats either a standard diet, or one high in fructose.

作為研究的一部分，調(diào)查報(bào)告的主要撰寫(xiě)人、美國(guó)亞特蘭大埃默里大學(xué)(Emory University)的康斯坦斯•哈勒爾(Constance Harrell)和她的團(tuán)隊(duì)給小鼠和成年鼠喂食了普通食物或是高果糖食物。

After 10 weeks, they exposed the rats to stress, forcing them to swim or putting them in an elevated maze.

十周后，他們對(duì)老鼠施加壓力，迫使他們游泳或是將它們置于高架迷宮中。

The teenage rats fed the high-fructose had a different stress hormone response to the test, including producing more of the stress hormone cortisol than the adult rats.

喂食高果糖的小鼠對(duì)測(cè)試表現(xiàn)出不同的壓力激素反應(yīng)，包括比成年鼠產(chǎn)生更多的壓力激素皮質(zhì)醇。

They showed depressed and anxious behaviour in response to the tests.

在測(cè)試反應(yīng)中，他們表現(xiàn)出抑郁和焦慮行為。

Scientists found that a genetic pathway in the brain that plays a key role in regulating the way it responds to stress was also altered as a result of the diet.

大腦中的遺傳神經(jīng)回路在調(diào)節(jié)大腦對(duì)壓力的應(yīng)對(duì)方式中扮演重要角色。科學(xué)家發(fā)現(xiàn)遺傳神經(jīng)回路也會(huì)因飲食而改變。

The findings indicate that eating a diet high in fructose throughout the teenage years may exacerbate depressive behaviours, researchers said.

研究者稱(chēng)，調(diào)查結(jié)果表明整個(gè)青少年時(shí)期都吃富含高果糖的飲食會(huì)加劇抑郁行為。

They may also affect the way the body and brain responds to stress, they added.

他們補(bǔ)充說(shuō)，這些高果糖飲食可能也會(huì)影響機(jī)體和大腦對(duì)壓力的應(yīng)對(duì)方式。

‘Our results offer new insights into the ways in which diet can alter brain health and may lead to important implications for adolescent nutrition and development,' Ms Harrell concluded.

“我們的研究結(jié)果對(duì)飲食會(huì)改變大腦健康以及可能對(duì)青少年?duì)I養(yǎng)與成長(zhǎng)埋下重大隱患提出了新的見(jiàn)解。”哈勒爾女士說(shuō)。

HOW THE BODY REACTS TO FRUCTOSE

機(jī)體是怎樣對(duì)果糖做出反應(yīng)的?

Although it is a simple sugar, glucose, rather than fructose is the body’s preferred energy source.

雖然葡萄糖只是一種單糖，但是身體最佳的能源卻是葡萄糖而非果糖。

Excess fructose in the body is turned into fat, which can lodge in the liver, leading to non-alcoholic fatty liver disease.

身體中過(guò)量的果糖會(huì)轉(zhuǎn)化為脂肪，積累在肝臟中，最終導(dǎo)致非酒精性脂肪肝。

Fructose puts an extra load on the liver, which in turn, prompts a range of problems, including raised levels of fat in the bloodstream.

果糖會(huì)對(duì)肝臟造成額外負(fù)擔(dān)，相應(yīng)的也就導(dǎo)致了血脂升高等一系列問(wèn)題。

The sugar can also lead to insulin resistance- where the body stops detecting insulin levels in the blood - and so produces even more insulin.

糖類(lèi)也會(huì)導(dǎo)致胰島素抵抗——這時(shí)機(jī)體停止檢測(cè)血液中胰島素含量——因而會(huì)分泌更多胰島素。

Insulin resistance is one of the key feature of metabolic syndrome, which could lead to type 2 diabetes, obesity and heart disease.

胰島素抵抗是代謝癥候群的主要特征之一，它會(huì)導(dǎo)致2型糖尿病、肥胖和心臟病。

High levels of insulin in the blood also blocks the action of 'hunger hormone' leptin, which tells the brain when fat cells have enough energy.

“饑餓激素”——瘦素，能幫助大腦識(shí)別脂肪細(xì)胞何時(shí)能量充足。血液中高濃度的胰島素同樣會(huì)阻礙瘦素作用的發(fā)揮。

So high levels of insulin lead to leptin resistance and therefore obesity.

因此，高濃度胰島素會(huì)導(dǎo)致瘦素抵抗，肥胖也隨之而來(lái)。