The Nuance
Can You Drink Too Much Water?
The old ‘eight glasses a day’ rule isn’t based on science, and experts say some of us may be overdoing it
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It’s 10:30 in the morning, and I’m already peeing for the fourth time today.
I peed when I woke up at 6:30 a.m. Then I drank a glass of water, had my habitual three cups of coffee, and peed a couple more times over the course of the next few hours. Now I’m peeing again.
My urine is clear. (It’s almost always clear.) If I drink another glass or two of water between now and lunchtime, and then five more glasses this afternoon and evening, I’ll have hit the eight-glasses-per-day target that everyone seems to think is the key to health and hydration. I’ll probably pee a dozen more times today.
Until recently, I thought I was doing everything right. Water, as the saying goes, is the essence of life. You need it or you die. And if there’s one thing nutrition experts seem to agree on, it’s that dehydration is bad and drinking lots of water is good.
But then I read this 2019 study in the journal Nutrients, which discusses the potential risks of overhydration. Its authors argue that drinking too much water is not only wasteful, but that over time it could lead to bladder distention, kidney dysfunction, or other problems. It cites case reports of otherwise healthy people who drank so much water that they developed swollen kidneys or ruptured urinary tracts.
The research on longevity and mortality is oddly silent on the subject of water consumption, and experts have called the search for a universal daily water requirement “elusive.”
“Urine is a waste product that helps your body balance its levels of sodium and other electrolytes,” says Tamara Hew-Butler, PhD, first author of that study and an associate professor of exercise physiology at Wayne State University in Detroit, Michigan.
If you’re peeing all the time and your pee is clear, she says, that’s an indication that you’re drinking more water than your body can use, and so you’re forcing it to dump fluids in order to…