"Drink 8 glasses of water a day”

“Drink your bodyweight in ounces”

“Drink a cup of water for every soda”

We all know we need water, but why? And how much should we actually be drinking?

It’s a fairly simple question, but the answer depends on a few factors. How much you weigh, the climate where you live, and how active you are. 

How Much Do You Weigh?

It’s no surprise that the bigger your body is, the more water you need. That’s because water is a vital molecule in the millions and billions of chemical reactions that are taking place in your body all the time! Every time you breathe, digest food, or do any other number of unconscious activities.

A good rule of thumb is generally between .5 and 1oz for every pound of body weight.(1) That means if you weigh 200lbs, you should be drinking between 100-200oz of water daily.


Where Do You Live?

The climate you live in has a very large impact on your water intake needs. If you live in an area with low humidity, or if the area you live in has lower humidity during the winter months, then you might consider adding extra water to your intake. 

Many people find that running a humidifier in their home is a great way to lessen the amount of water they lose through breathing.

What is Your Activity Level?

We’re all familiar with sports performance drinks that claim to rehydrate you after a tough workout, but the reality is that most of what you need is just water. Unless you’re working out in intense heat or exercising at a high intensity for more than 60 minutes, you’ll be better off with water than sports drinks like Gatorade.(2) 

The amount of water you should drink after exercise is actually pretty simple. If you’re able to weigh yourself before and after exercise, then you simply drink the amount of water lost during exercise. If you lose 1lb through sweat, then you should drink at least 1lb, or 16oz of water. If you don’t have a scale convenient, then you can generally drink 8-16oz of water after a moderate 30-45 minute workout.

Don’t forget to hydrate before you workout! While replacing water is important, it’s also important to plan ahead. Drinking an extra 16oz of water a few hours before your workout, and another 8oz up to 30 minutes before starting, is generally accepted as a good way to prepare for exercise.(3)

Listen to Your Body

While there is all this math available to figure out how much water you need, you should also listen to your body. If you’re thirsty, you should be sure to drink water and rehydrate. It’s always better to have a steady intake of water throughout the day so as not to drink too much at once and overwhelm your body. As always, remember to discuss any issues or major changes with your physician.