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True: You need water.
Water is the most important substance you consume. A human can survive about two months without food but would die in just seven days without water.
Not True: Dark urine means you’re dehydrated.
Contrary to popular belief, dark urine doesn’t necessarily mean you’re dehydrated. Urine can be darkened by some medicines and foods, such as asparagus or beets.
True: You should drink when you’re thirsty.
In most cases, thirst is a reliable signal that your body needs water. Another body indicator that you need to drink up: If you’ve gone many hours without urinating.
Not True: Drinking water prevents wrinkles.
Drinking water doesn’t moisturize skin, prevent wrinkles or create a glowing complexion in people who are otherwise well-hydrated. The best way to prevent dry and damaged skin is with a topical moisturizer and sunscreen.
True: Drinking enough water protects against kidney stones.
Good hydration will greatly decrease your risk of kidney stones, and there is evidence that being well-hydrated counters constipation and exercise-induced asthma.
Not True: You need to drink eight glasses of water a day.
Despite the importance of water, there is little evidence about how much is needed. The Institute of Medicine states that an “adequate intake” of water ranges from 700 milliliters (about 3 cups) a day for newborns to 3.8 liters (16 cups) for lactating women. Also, all kinds of liquids — including coffee, tea, juices and even some foods — contribute to your daily intake of water.