How Much Water Should You Drink a Day
Virginia Morrow
how much water should you drink a day

Water is vital for life. Plants, animals, and humans alike rely on water to sustain themselves. It even makes the list of the 6 essential nutrients. Without any water consumption, you can only survive for a few days, far less than the amount of time people can live without food. But how do you know how much water to drink? We have all experienced dehydration, but what does water really do in our bodies, and how can we make sure to get the right amount to avoid those effects?

What does water do in the body?

Water is an important factor in almost everything your body does. Acting as a one stop shop, water helps the bloodstream by regulating blood sugar and facilitating the transportation and absorption of nutrients. It helps the digestion system by making sure everything moves smoothly. It regulates body temperature like a coolant when you sweat, and it helps you create saliva and urine, which are both essential. Water flushes waste, assisting the liver and kidneys, and it hydrates every single cell in the body. The list of foundational necessities fulfilled by water is literally endless. It makes sense then that over 60% of our bodily mass is composed of water. In children, it is closer to 75%. 

When you don’t get enough water per day, dehydration sets in. This has short term effects like cloudy thinking and fatigue, and long term effects like an increase in your risk for developing health disorders or kidney stones. 

So how much water should I drink every day?

In order to keep your metabolism working hard and improve all of your health variables, it is important to not fall behind on water consumption. Even one day of exercise or heat could dehydrate you enough to interrupt your bodily processes for a few days. In those scenarios, you have to prep and follow up with extra water. 

The amount to consume each day relies on myriad factors. Age, gender, height, weight, environment, and more all weigh into the equation. Luckily, there are some guidelines to follow. The Institute of Medicine of the National Academies conducted an often referenced report that concluded with a solid number. The average healthy, hydrated woman should consume around 2.7 liters of water in total (from both food and beverage intake) and men around 3.7 liters. Most of that should come in liquid form, but relying on food to cover half to a full liter of that number is recommended. That much water is fitting, however, only for a non-athlete in a temperate climate. Factors like how much you work out and how hot your environment is make you sweat more and contribute to your overall water intake numbers. When in doubt, sip some more. 

Traditionally, people grow up hearing about the 8 glasses per day rule of water consumption. The reality is much more individual than that, as reflected in the advice from the NAIM study. A good way to keep drinking water is by setting challenges with coworkers or friends. This keeps you both accountable to drink more water. Most people consume some amount of their recommended daily intake of water through other beverages or foods that hold water. Typically, fruits and veggies hold the most water, but foods like yogurt, pasta, and meat also play a role in hydration.

As a general rule, relying on thirst is often enough to maintain the right level of hydration. According to WebMD, keeping a good reusable water bottle near you at work or home can encourage you to drink intermittently as needed. That way, your thirst is in control of your hydration needs.

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