Expert Answers to Readers’ Questions
How much water do I need to drink each day?
It’s impossible to set a single requirement for how much water the hypothetical average American needs each day. The amount you need depends on how much you eat, what the weather is, and how active you are. So instead of setting an estimated average requirement for water, as it has done for other nutrients, the Institute of Medicine has set an adequate intake of 125 ounces (about 15 cups) for men and 91 ounces for women (about 11 cups). Note that this is not a daily target, but a general guide. In most people, about 80 percent of this comes from beverages; the rest comes from food. As for the oft-repeated nutrition advice to “drink eight glasses of water every day,” there’s little evidence to support it, but this would be one excellent way to fulfill most of a person’s fluid requirement.
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