Water: Do You Need 8 Glasses a Day?
How much water do you really need? Our experts weigh in.
When it comes to quenching your thirst, water rules. But when it comes to knowing how much water you should drink every day, opinions are all over the map.
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Should you buy a 2-liter water bottle to get your 8 ounces in every day? Or is drinking when you’re thirsty enough to satisfy your fluid needs?
“The range of fluid intake needs is quite broad, depending on your metabolism, activity level, ambient temperature and age,” says preventive medicine specialist Roxanne Sukol, MD. “It’s better to focus on urine output: if it’s almost clear, you’re good. If it’s dark yellow or has a strong odor, try fixing it with a couple of glasses of water.”
Your diet also matters, adds registered dietitian Mira Ilic, RD, LD. “Nutritional guidelines cover all fluids, including the water found in food, juice, tea, soup and milk,” she says. “Eating a lot of fruits and vegetables — on their own, or in juice or soup — can help you can meet 20 percent of your fluid needs.”
Your health is another key factor, notes internist Melissa Klein, MD. “Fluid needs increase when you’re sweating from a fever because you lose more water through your skin,” she says. “When you lose a lot fluid, whether it’s from sweating or diarrhea, we encourage you to drink fluids with water, salt and sugar to keep your body balanced.”