Do You Actually Need to Drink 8 Glasses of Water Each Day?

Everyone’s heard the old axiom that we’re supposed to drink eight glasses of water a day. Otherwise, we risk being “chronically dehydrated,” right?
But do we really need to drink that many glasses of water?
 The short answer is no, not really, but there’s a little more to it than a simple yes or no. Your water intake needs vary based on several factors, including health conditions, where you live, and how active you are.
So, what’s the deal with the recommended eight glasses?




How This Idea Originated:

Way back in 1945, the National Academy of Sciences Food and Nutrition Board released a publication stating that “a suitable allowance of water for adults is 2.5 liters daily in most instances.” This equates to about eight glasses.
There’s just one thing that a lot of people tend to leave out, however. The original recommendation also mentioned that “most of this quantity is contained in prepared foods.”


In other words, most healthy adults may not need to go all crazy on the water consumption. And this is especially true if lots of fruits and veggies are consumed. Plus, as many nutritionists at the time also noted, many other beverages also count to some degree as well. Even other sources to which the idea has been attributed mentioned the same.

How Much Water Should You Drink Each Day?





There is no single answer to this question.

Adequate intake (AI) of water in the US is considered to be 91 ounces (2.7 liters) per day for women and 125 ounces (3.7 liters) per day for men (22).

Note that this is the total intake of water from all sources, not just pure water.

While this may certainly be used as a guideline, there are a number of factors, both inside your body and in your environment, that influence your need for water.

Body size, composition and activity level vary greatly from person to person. If you’re an athlete, live in a hot climate or are currently breastfeeding, your water requirements increase.

Taking all this into account, it’s clear that water needs are highly individual.

Drinking eight glasses of water per day may be more than enough for some people, but it may be too little for others.

If you want to keep things simple, just listen to your body and let thirst be your guide.

Drink water when you’re feeling thirsty. Stop when you’re not thirsty anymore. Make up for fluid loss by drinking more during hot weather and exercise.

However, keep in mind that this does not apply to everyone. Some elderly people, for example, may need to consciously remind themselves to drink water even if they’re not thirsty.

Read this for a more detailed overview of how much water you should drink per day.