Despite what Doctor Who suggests, it does't just grow legs and walk away.

無論《超時空博士》怎麼說，脂肪並不會自己長腳走開。

It actually disappears into thin air!

但它是真的會消失在空氣中！

Hey guys. Julia here for DNews.

大家好，我是 DNews 的 Julia。

New year brings new resolutions.

新年帶來新希望。

For many, that means getting back to the gym.

對於許多人來說那就是重返健身房。

"Feel the burn!" seems to be the rallying cry for exercise enthusiasts everywhere.

「感受脂肪燃燒！」似乎就是各地運動狂一致的吶喊。

And how many magazines have flashy covers like "10 new ways to burn fat in the new year"!

多少雜誌有「新年十種燃脂新方法！」這種奪人眼目的封面

And what does that even mean? How can you "burn fat" and where does it go?

但這到底是什麼意思啊？你要怎麼「燃燒」脂肪呢？脂肪跑去哪裡了？

When you eat too much protein or carbs, your body converts it and stores it as fat.

當你攝取太多蛋白質或碳水化合物時，你的身體會把它轉換成脂肪儲存起來。

To get your body to "burn" up these cells, your body has to use up the immediate energy from food, and dip into your energy reserves.

為了要讓身體「燃燒」這些細胞，身體得耗盡食物中立即可使用的能量，才會進一步使用儲存起來的能量。

In other words, you burn more calories than you take in, so you have to use your fat stores.

換句話說，你得消耗多於你所攝取的卡路里，才會使用到儲存起來的脂肪。

And that adipose tissue or fat is made up fat cells called adipocytes filled with molecules called triglycerides.

脂肪組織或脂肪是由充滿三酸甘油脂分子的脂肪細胞所組成。

When you're trying to "burn fat", you're really trying to get rid of these triglycerides.

當你在「燃燒脂肪」時，其實就是在消除這些三酸甘油酯。

High levels of which are linked with heart disease and metabolic syndrome.

過多的三酸甘油酯被認為與心臟疾病和代謝症候群有關。

Triglycerides are made up of glycerol and three fatty acids.

三酸甘油脂是由一個甘油和三個脂肪酸所組成。

In order to burn fat, you have to oxidize these molecules.

要燃燒脂肪，你得氧化這些分子。

Now the complete oxidation of a single triglyceride involves many biochemical processes and enzymes.

而要完全氧化一個三酸甘油酯，牽涉許多生化反應及酵素。

But the process can be boiled down to a single chemical equation.

但這些反應可以總歸成單一個化學式。

Now this may look complicated but what's basically happening here is that when you're exercising, you're tapping into your fat stores.

這看起來可能有點複雜。基本上是這樣的，當你運動時，就是在汲取儲存起來的脂肪。

So you are "oxidizing" or breaking down that molecule to release carbon dioxide, water, and energy.

所以你就是在「氧化」或者分解這個分子，然後釋放二氧化碳、水和能量。

I bet you're imagining that most of that fat gets turned into energy like your gym teacher or personal trainer tells you.

我猜大家應該認為大部分的脂肪會轉換成能量，就像你的健身老師或私人教練告訴你的一樣，

Well, they'd be wrong.

其實他們錯了。　　　

According to a study published in the British Medical Journal, most of the fat turns into carbon dioxide and water.

根據英國醫學期刊上發表的一篇研究，大部分的脂肪轉換成二氧化碳和水。

According to their calculations, 84% of an adipose triglyceride is given off as CO2.

根據他們的計算，84% 脂肪中的三酸甘油酯以二氧化碳釋出。

So for example, if you lose 10 kg of fat, 8.4 kg is exhaled as CO2.

舉例來說，若你減了 10 公斤的脂肪，其中 8.4 公斤是以二氧化碳的形式被呼出。

As the lead author says, when someone burns fat, "most of the mass is breathed out as carbon dioxide. It goes into thin air"

帶頭做這篇研究的作者表示，當某人燃燒脂肪時，「大部分的質量是以二氧化碳形式隨呼吸排出，混入空氣中。」

The rest is given off as water in some way or another, like in urine, sweat, tears or other bodily fluids.

剩下的水則以其他方式釋出，像是混入尿液、汗水、眼淚或其他體液中。

The authors also calculated about how much carbon dioxide we give off in an average day.

作者還計算我們每日平均的二氧化碳釋放量。

Even without hitting the treadmill, with every breath we take, we give off 33 grams of carbon dioxide. Woohoo!

即使沒有使用跑步機，每次呼吸我們都釋放約 33 克的二氧化碳。唷呼！

But before you get too excited about losing all that CO2 and burning all that fat, the authors also note that a single muffin contains 20% of your daily intake of energy.

但也別因為這些消耗的二氧化碳和脂肪就瞎開心，作者也提到，單單一個馬芬蛋糕就佔每日攝取熱量的 20%。

A single, lousy, muffin.

只要一個討人厭的馬芬蛋糕。

So a small amount of food can quickly make all that exercise for naught.

所以一丁點食物就能夠讓那些運動徒勞無功。

But if you do want to get more bang for your breath, you can actually measure how much fat you're burning by measuring your breath.

如果你真的想要讓你的呼吸更有效率的話，你其實可以測量你的呼吸，得知有多少脂肪被消耗掉。

So if you want to stick to that new year's resolution, take a deep breath, hit the gym and feel the burn.

若你想要讓你的新年希望一直保持下去 ... 深呼吸進到健身房，感受脂肪燃燒吧！

Losing weight in the future will be weird.

未來，減重可能會變得很奇怪。

Not only will your breath keep track of how much fat you're burning, but an algorithm will decide what you should be eating!

不單是你的呼吸會記錄你消耗了多少脂肪，還有一種演算法會告訴你該吃什麼！

To find out more about that, check out this episode right here.

想要知道更多的話，可以看一下這裡的影片。

Microbians are the ecosystems living in all of us. Each of us carry around millions of micros in our guts.

微生物是生活在我們體內的生態系統。我們每個人的內臟都含有百萬個微生物。

And other studies like one published in the journal Science found that guts bacteria could be the crucial factor in a person's metabolism.

其他研究像是刊登在《科學》期刊的一篇指出，內臟菌種會大大影響一個人的新陳代謝。

We know you love watching online, but we're excited to announce DNews is now on Science channel!

我們知道大家喜歡線上收看，我們也很高興地宣布 DNews 現在已經在科學頻道中！

Trace and Amy will be sharing a minute of the best in science in between awesome programming.

Trace 和 Amy 將會分享各個科學節目中最精彩的時刻。

So check out as Science Presents DNews at 9! Every weeknight, Monday through Friday, and use your Twitter to let them know if you want more!

每晚 9 點來科學頻道的 DNews 看看吧！週一至週五每晚都有若想知道更多，可以用 Twitter 告訴他們！

So how do you guys exercise or keep in shape? Let us know!

大家都是怎麼運動或保持身材的呢？讓我們了解一下吧！

You can tell us down in the comments below. Don't forget to hit those likes and subscribe buttons while you add it.

你可以在留言區告訴我們。別忘了按個喜歡，然後訂閱加入我們的頻道。

And keep coming back to DNews so you don't miss a single episode.

還有記得回來 DNews ，你才不會錯過任何一集。