How much water should you drink in a day?
There are many theories about the health benefits of proper hydration for the body. It is claimed that drinking enough liquids can make the skin look younger and more radiant, prevent cancer, and even protect against COVID-19.
While the scientific evidence for all of these effects remains mixed, one thing is clear: The human body does not like to be low on water.
The recommendation to drink eight glasses of water a day isn’t supported by any rigorous science. Researchers believe it stems from a 75-year-old report that has been repeated so often it has simply become the norm.
Back in 1945, a study in the U.S. concluded that an adult human should consume 1 milliliter of fluid for every calorie eaten. If you consume a diet of about 2,000 calories, that comes out to 8 and a half cups of water a day.
The U.S. National Academies of Sciences, Engineering, and Medicine has calculated that men need 3.7 liters and women need 2.7 liters of fluid a day. That number is calculating water, other beverages, and the liquid you'll get from fruits and vegetables in a balanced diet.
“If we’re not hydrated, then our body is in a state of stress,” says Melissa Majumdar, M.S., R.D., dietitian at Emory University Hospital and a spokesperson for the Academy of Nutrition and Dietetics. “And we do know that states of stress can lead to chronic disease.”
When you’re severely dehydrated, your body will release the stress hormone cortisol, and that can have a negative effect on weight, blood sugar, and cardiovascular health. AS we experience a year of great stress due to the pandemic, there’s never been a better time to drink more water.
Water aids in digestion, clearing bacteria out of your body, protecting your organs and tissues, regulating body temperature, and maintaining electrolytes. But consuming too much water can flush out too many necessary electrolytes.
Some factors in how much water you need are weight, exercise, underlying health issues and pregnancy.