How much water should you drink daily?
Drinking water is kind of non-negotiable when it comes to, you know, living. But while we all pretty much know we have to drink water to keep our bodies functioning, we can’t seem to agree on just how much water we need.
The truth? Water intake isn’t exactly a one-size fits all prescription. Instead, how much water you need to drink each day is dependent on a bunch of different factors: your weight, how your metabolism works, how much food you eat (and what you eat), what your body temperature is, and how active you are, among other things.
So, the “8 x 8” rule—drinking eight 8-ounce glasses of water a day—is pretty solid advice as a starting point, says Cynthia Sass, RD, Health contributing editor. But “you need to consume more fluid if you’re losing more, through exercise or from being in hot, humid weather,” Sass explains. “You may also need more if you’ve been ill and have a fever, are sweating, or are experiencing vomiting and diarrhea.”
The Institute of Medicine of the National Academies takes it a step further and suggests women consume an average of 2.7 liters (about 11 cups) of water each day. Note, however, the institute says “consume”—that’s because you can get your water intake from both beverages and food. “We don’t offer any rule of thumb based on how many glasses of water people should drink each day because our hydration needs can be met through a variety of sources in addition to drinking water,” Lawrence Appel, director of the Welch Center for Prevention, Epidemiology and Clinical Research at Johns Hopkins University, said in a press release for the institute.