Usually, you can’t go wrong with H2O. It keeps us hydrated (obviously), helps us avoid overeating, and could even burn extra calories. But, like with many of your healthiest habits, more isn’t always better, even when it comes to water. Believe it or not, there are a few times when you should back off the bubbler.
It’s incredibly rare, but it’s possible to drink so much water you put your health at risk. If you chug enough to dilute your body’s natural balance of salt, you can become too low in sodium, a condition known as hyponatremia. Endurance athletes, for example, may be tempted to keep on sipping all throughout a marathon (or after), leading to cell swelling that can cause nausea, vomiting, seizures, and even death. (Here’s how much water to drink every day, plus 4 other healthy habits you’ve got all wrong.)
Hyponatremia can also be caused by certain issues with the liver, kidney, heart, or pituitary gland, says integrative physician Taz Bhatia, M.D., as well as by certain medications, like diuretics, antidepressants, and pain medications.
So how do you know when enough water is enough? Forget that old “eight glasses a day” rule and instead take a look in the toilet. If you see a light lemonade shade, you’ve reached optimal hydration status. If you see only clear urine in the bowl, you can probably cut back your water intake a smidge. Darker yellows can be a sign it’s time to get sipping.
It’s one of the simplest ways to cut back on a few calories: Drink a glass of water before a meal (or when a craving strikes) and you’ll naturally eat a little bit less since that fluid is already taking up space in your fist-sized stomach. But for the very same reason, drinking too much water before or during a heavy meal can lead to discomfort. “Drinking more water may only leave you feeling even more bloated,” Bhatia says. (Get the secret to banishing belly bulge from WH readers who’ve done it with Take It All Off! Keep It All Off!)
We lose electrolytes, like potassium and sodium, through sweat. If you’re seriously sweating it out, you’ll need to replace those crucial nutrients, which aren’t found in plain water. Rather than a sugary sports drink, though, you may be able to get the same boost from coconut water, which is naturally high in potassium, magnesium, sodium, and vitamin C without as many calories and with more fiber.
We get it: No one wants to drink regular water when there are all these fancy flavored bottled varieties to choose from. But flavored waters often rely on zero-calorie sweeteners to add a little something something to the plain ol’ water taste. Because these sweeteners have been linked to increased hunger and even weight gain in some studies, commercially available flavored waters might do you more harm than good. Instead, try adding your own flavor to tap water by tossing in lemon, lime, cucumber, watermelon, berries, or even herbs.