we look so feverishly for water on other planets across the universe, and consume it consistently

我們迫切尋找宇宙中其他具有水源行星 就像

every day here on Earth. So what would happen to your body if you stopped drinking water?

在地球每天使用的水資源一樣 所以 當你停止攝取水份身體會產生什麼問題呢?

Of course, when we say 'water' we're including all fluids which simply contain water - like

理所當然 所謂的「水」 包含任何可飲用的液體 例如

juices, pop, or tea. Much like the desire to breath in oxygen, thirst is a survival

果汁 汽水 或是茶 感到口渴與吸入氧氣一樣是種生存本能

instinct. H20 is the most abundant molecule in the human body making up, on average, 65%

水分子佔人體的絕大部分 成人體內的水平均約佔65%

of an adult. As a universal solvent, it carries nutrients and hormones through the body, regulates

水是萬能的溶劑 可以幫助體內輸送營養和賀爾蒙 調節體內溫度

body temperature, cushions our joints and even lubricates our eyes. You produce around

緩解關節間的摩擦 甚至是滋潤我們的雙眼 你每天大約排出

1.5 litres of urine every day, with another litre lost from breathing, sweating and...pooping.

1.5公升的尿液 加上其他像是呼吸 流汗 或排便也會流失水分

So it's essential that the body replaces this liquid.

所以體內的水循環是非常重要的

The thirst centre of the brain is located in the hypothalamus, and is constantly using

口渴的感覺中樞位於大腦的下視丘 經常藉由

sensors in your blood vessels to monitor the amount of sodium and other substances in your

血管中的感應去監控鈉含量及其他物質

body. For example, if you sweat too much, your blood volume and pressure fall. The brain

舉例來說 如你排汗量多時血量和血壓都會降低

then detects this change and creates the urge to drink something, NOW! So what happens if

大腦偵測到這樣的改變就會產生想喝水的欲望

you are unable to satisfy this thirst?

如果無法止渴會發生甚麼事呢?

The initial signs of dehydration are the obvious dry mouth, following which your urine becomes

初期的脫水會造成明顯的口乾舌燥 接下來你的尿液會變得

darker with a stronger odor, as your body attempts to conserve more fluids. The lack

色深以及難聞 因為身體開始減少水分的浪費

of H20 then begins to affect your brain - you may feel light headed, have a slower response

缺乏水分子會進而影響到大腦 你可能會感到頭昏眼花 反應遲緩

time and decreased ability to feel pain. In fact, when you're dehydrated, your brain tissue

或是對疼痛感覺麻痺 事實上 當身體脫水時 大腦的組織會逐漸萎縮

literally shrinks. In studies observing hydrated vs. dehydrated participants, the same task

許多研究中觀察未脫水與脫水受試者的反應

required more brain power and oxygen in dehydrated individuals compared to those fully hydrated.

相較於水分充足的人 脫水的人耗費更多腦力與氧氣來完成相同任務

After a day or two with no fluids you'll stop peeing all together, have trouble swallowing,

若一兩天未攝取水分 身體將會減少排尿 吞嚥困難

suffer from muscle spasms and likely experience nausea - after all, your body can survive

肌肉痙攣 噁心反胃 畢竟在沒有食物的情況下

without food much longer, and attention to digestion is not a priority at this point.

能存活比較久 所以消化系統在這時候並不重要

Eventually, victims may become delirious with severely impaired brain function. Interestingly,

最終 身體缺水的人會變得神智不清 大腦功能會嚴重受損

studies looking at elderly patients who suffer from delirium, found that many are simply

研究發現年老的神智不清患者 多半僅僅是

suffering from chronic dehydration in the first place. After even more time without

一開始就歷經長期的脫水 加上之後又長期未攝取水分

water, the blood stops flowing to your skin, reducing heat loss but increasing your core

血液會停止流向皮膚 以減少熱能耗損 但身體的核心溫度卻會增加

body temperature. This can lead to a grey-blueish tinge to your skin. Beyond 3-5 days without

這會導致皮膚呈現灰青色 三到五天內未攝取水份

water, and your body will begin to shut down it's organs, and eventually the brain.

身體器官會逐漸衰竭 最後連大腦也無法運作

Of course, unlike the plentiful oxygen we breath, only 2.5% of all Earth's water is

當然 不像我們有足夠的氧氣可以呼吸 地球上只有約2.5%的乾淨水源

fresh; most of which is locked up in glaciers, ice caps and underground lakes known as aquifers,

而且大部分都封藏於冰河 冰冠 及地下水層

leaving less than 1% available for drinking. And most of this water is actually used to

真正可以飲用的水剩不到1% 然而這些水又被用來

grow crops; approximately 500 billion litres of freshwater is used daily for agriculture

灌溉穀物 約有五千億公升的乾淨水源被用來農業灌溉

in the USA alone, with another 500 billion litres to cool electric power plants. And

就美國來說 更用了五千億公升的水來冷卻核能燃料棒

as our personal drinking sources become increasingly contaminated, over 783 million people on earth

加上可飲用水源汙染日益嚴重 約有7.83億的人

are unable to access clean water.

無法攝取到乾淨的水源

Scientists around the world are trying to find solutions to this problem - from attempts

科學家積極地找出這些問題的解決方案-

to remove salt from ocean water, tap into underground aquifers and creating innovative

從淡化海水 開發地下水源 到發明創新的濾水系統

water filtration systems. If we look to space, NASA has developed technology for astronauts

就太空科技而言 NASA已發展出一項技術

to turn their urine into water more pure than what we drink on earth. But we can't just

能淨化太空人的尿液 甚至比飲用水還乾淨

rely on science and technology - perhaps the solution relies on us as a species to understand

不過僅仰賴科技是不夠的 - 也許這些問題是需要我們去深入瞭解的

and contribute to this global water crisis.

並致力於去解決全球水資源危機 這些問題才可能得以解決

If you want to help in the mission to end global thirst, join in World Water Day on

如果你想為我們的地球盡一份心力 快來參加3月22號的世界水資源日

March 22nd. There are a lot of really amazing projects out there, like Water.org or even

這裡有很多有趣的活動 例如Water.org

the awesome UNICEF app which donates 1 day of clean water to child in need, for every

甚至是 UNICEF(聯合國兒童基金會)每十分鐘將會捐助一天所需水分給需要的孩童

10 minutes you put your phone down. We'll leave links in the description for these and

這只需要你來電 我們會在說明區中留下連結

other great water charities. Small investments really do make a huge difference.

期待著你的愛心 小小的愛心會轉動整個地球

We'll be donating all the proceeds from this video to a water project close to us called

我們會將這支影片的所得捐贈給最鄰近的"摩洛哥5個村莊"水資源計畫

Morocco 5 Villages - so thanks for supporting and watching. And subscribe for more weekly

感謝您的支持與收看

science videos!

請你持續訂閱更多每周的科學影片!