It’s Hot! It’s Summer! How Much Water Do You Need?

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

Dive into some water facts to find out why: The average adult human body is 50-65% water. The percentage is about 60% in men, 55% in women, 65% in children and about 75% in infants.

Water keeps you alive

• 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.

Lack of water lead to dehydration, and that’s not good. People feel thirsty when they lost 2-3% of their body’s water. But keep in mind that mental performance and coordination start to be impaired when they’ve lost about 1% of their body’s water.

How much water do you need?

So how much water does the average, healthy adult need every day? 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.

The good news is 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.

—Frank Graff

 Frank Graff is a producer/reporter with UNC-TV, focusing on Sci NC, a broadcast and online science series.