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How Much Water Do We Need to Drink?

It’s the thirsty season

Whether you’re working in the yard or lying on the beach in the heat of summer, you are going to be sweating and you’re going to get thirsty. And while it’s tempting to reach for a cold beverage (of any kind), it’s a good idea to drink just plain water first.

Heres why:

The average adult human body is 50-65 percent water. The percentage is about 60 percent in men, 55 percent in women, 65 percent in children and about 75 percent in infants. That’s a lot of water and it needs to be replenished, because it turns out water does a lot for our bodies. 

  • Water helps regulate body temperature.
  • Water lubricates and cushions joints.
  • Water protects sensitive tissues.
  • Water is needed to metabolize proteins and carbohydrates in food.
  • Water is used to flush waste and toxins from the body.
  • Water carries oxygen and nutrients to cells.


Bottom line, or should I say the water line, is that a lack of water leads to dehydration, and that’s not good. 
People feel thirsty when they’ve lost 2-3 percent of their body’s water. But keep in mind that mental performance and coordination start to be impaired when about 1 percent of the body’s water is lost.

Now let’s go back to the original question-how much water do you need?

The National Academies of Sciences, Engineering, and Medicine recommends:

  • About 15.5 cups (3.7 liters) of fluids for men
  • About 11.5 cups (2.7 liters) of fluids a day for women.


That amount varies depending on age, activity level and where you live. The good news is that these recommendations cover getting water from fluids, other beverages, and food. About 20 percent of daily fluid intake usually comes from food and the rest from drinks. 

So what about that 8 glasses of water/day advice? Doctors say it’s a reasonable goal and it’s easy to remember. The best advice is to stay hydrated by drinking water and other fluids whenever you are thirsty.