At first detection of low water levels, sensory receptors in the brain's hypothalamus signal the release of antidiuretic hormone.
体内开始侦测到水分过低时，脑部下视丘的感应接收器就会发出讯号，通知释放抗利尿激素。
When it reached the kidneys, it creates aquaporins,
当ADH抵达肾脏时会造成水孔蛋白，
special channels that enable blood to absorb and retain more water, leading to concentrated, dark urine.
一种特殊的通道使血液吸收并保留更多水分，造成浓缩及深褐色的尿液。
Increased dehydration can cause notable drops in energy, mood, skin moisture, and blood pressure, as well as signs of cognitive impairment.
脱水加重会造成明显的精力减退、心情不振、皮肤变干、低血压以及认知障碍的症状。
A dehydrated brain works harder to accomplish the same amount as a normal brain,
脱水的脑会比正常的脑更难完成同等份量的工作，
and it even temporarily shrinks because of its lack of water.
甚至会因为缺水而暂时萎缩。
Over-hydration, or hyponatremia, is usually caused by overconsumption of water in a short amount of time.
体内水分过多，也就是低钠血症，通常是因为短时间内摄取过多水分造成的。
Athletes are often the victims of over-hydration because of complications in regulating water levels in extreme physical conditions.
运动员通常是过度脱水的受害者，这是因为一些并发症造成的。这些并发症由极端身体情况下水含量的改变引起
Whereas the dehydrated brain amps up the production of antidiuretic hormone,
当脱水的大脑促进抗利尿激素生成时
the over-hydrated brain slows, or even stops, releasing it into the blood.
过度脱水的大脑会变慢，甚至停止运行，并把此激素释放到血液中。
Sodium electrolytes in the body become diluted, causing cells to swell.
体内的电解质钠被稀释，造成细胞水肿。
In severe cases, the kidneys can't keep up with the resulting volumes of dilute urine.
严重的情况下肾脏会无法负荷大量被稀释的尿液。
Water intoxication then occurs, possibly causing headache, vomiting, and, in rare instances, seizures or death.
水中毒随之而发生可能导致头痛、呕吐，少数严重者甚至会痉挛或死亡。
But that's a pretty extreme situation.
但那是一种非常极端的状况。
On a normal, day-to-day basis, maintaining a well-hydrated system is easy to manage
在一般日常生活中保持体内水平衡非常容易
for those of us fortunate enough to have access to clean drinking water.
对我们这些相当幸运可以取得干净饮水的人而言。
