什么饮料最解渴？白水、茶还是汽水？都不是！苏格兰科学家的研究发现，最补水的饮料含有乳糖、蛋白质和脂肪，你猜出来是哪种饮料了吗？
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When you're thirsty and in need of a drink, which beverages are best at keeping you hydrated?
如果你感到口渴需要喝点东西，哪种饮料最解渴呢？
Sure, you can always reach for a glass of water -- but plain H20 isn't the most hydrating beverage around, according to a study from Scotland's St. Andrews University that compared the hydration responses of several different drinks.
当然，你总是可以喝水的——但是根据苏格兰圣安德鲁斯大学的一项研究，白水并非最解渴的饮料。这项研究将几种不同饮料的解渴功效做了对比。
The researchers found that while water -- both still and sparkling --does a pretty good job of quickly hydrating the body, beverages with a little bit of sugar, fat or protein do an even better job of keeping us hydrated for longer.
研究人员发现，尽管水（包括白水和苏打水）能够迅速给身体补水，但是，含有一点糖、脂肪或蛋白质的饮料补水效果更长久。
The reason has to do with how our bodies respond to beverages, according to Ronald Maughan, a professor at St. Andrews' School of Medicine and the study's author. One factor is the volume of a given drink: The more you drink, the faster the drink empties from your stomach and gets absorbed into the bloodstream, where it can dilute the body's fluids and hydrate you.
这项研究的作者、圣安德鲁斯大学医学院教授罗纳尔德·莫恩说，原因和我们的身体对饮料的反应机制有关。一个因素是饮料的摄入量：你喝得越多，饮料从胃里排空并被血流吸收的速度越快，从而稀释体液，给你补水。
The other factor affecting how well a beverage hydrates relates to a drink's nutrient composition. For example, milk was found to be even more hydrating than plain water because it contains the sugar lactose, some protein and some fat, all of which help to slow the emptying of fluid from the stomach and keep hydration happening over a longer period of time.
另一个影响饮料补水功效的因素和饮料的营养成分有关。例如，研究人员发现，牛奶的补水功效甚至比白水更佳，因为牛奶含有乳糖、蛋白质和脂肪，这些成分都有助于减缓液体从胃里排空的速度，延长补水的功效。
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Milk also has sodium, which acts like a sponge and holds onto water in the body and results in less urine produced.
牛奶还含有钠，钠可以像海绵一样在身体里留住水分，并导致产生的尿液减少。
The same can be said for oral rehydration solutions that are used to treat diarrhea. Those contain small amounts of sugar, as well as sodium and potassium, which can also help promote water retention in the body.
用来治疗腹泻的口服补水溶液也可以有同样的补水功效。那些含有少量糖、钠和钾的饮料也可以帮助人体留住水分。
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想要补水效果好 糖多不如糖少
But here's where it gets tricky: Beverages with more concentrated sugars, such as fruit juices or colas, are not necessarily as hydrating as their lower-sugar cousins. They may spend a little more time in the stomach and empty more slowly compared to plain water, but once these beverages enter the small intestine their high concentration of sugars gets diluted during a physiological process called osmosis. This process in effect "pulls" water from the body into the small intestine to dilute the sugars these beverages contain. And technically, anything inside the intestine is outside your body.
但是问题就在这里：糖浓度更高的饮料（比如果汁或可乐）的补水效果就不一定有含糖量低的饮料好了。和白水相比，这些饮料也许在胃里停留的时间更长一点，排空速度更慢，但一旦这些饮料进入小肠，高浓度的糖就会在渗透作用（一种生理过程）下得到稀释。这一过程会“抽出”人体的水分来稀释小肠中的饮料糖分。严格意义上来讲，小肠内部的任何物质都会排出体外。
Juice and soda are not only less hydrating, but offer extra sugars and calories that won't fill us up as much as solid foods. If the choice is between soda and water for hydration, go with water every time. After all, our kidneys and liver depend on water to get rid of toxins in our bodies, and water also plays a key role in maintaining skin's elasticity and suppleness. It's the cheapest moisturizer you'll find.
果汁和汽水不但补水功效更差，而且会提供过多的糖分和热量，而且不会像固体食物一样令我们产生饱腹感。如果要在汽水和水当中选一个来解渴，你肯定要选水。毕竟，我们的肾和肝依靠水来排除身体里的毒素，而且水对于保持皮肤的弹性和柔软也起到了关键作用。水是你能找到的最便宜的润肤品。
While staying hydrated is important -- doing so keeps our joints lubricated, helps prevent infections, and carries nutrients to our cells -- in most situations people don't need to worry too much about how hydrating their beverages are.
尽管补水很重要——可以保持关节润滑，帮助防止感染，将营养输送到细胞——不过，在大多数情况下人们不需要太担心饮料的补水效果。