How to Calculate the Right Amount of Water You Need to Drink Every Day

Each year, people drink more than 4 trillion cubic meters of fresh water. You’ve probably heard that you, alone, need to drink 8 cups of water per day for all the processes inside your body to function well. However, the number is not entirely correct, and in this article, we’ll explain how things actually stand.
We at Bright Side want to share the formula with you. It’ll help you identify how much water you should drink per day.
How the myth about the standard “8 glasses of water a day” came to be
All of our organs consist of water — the heart and brain are 73% water while the lungs are 83% water, for example. The idea that a person has to drink 8 glasses of water per day to keep those organs and the entire body hydrated is quite popular.
However, these 8 glasses we hear about so often are not a rule but a mid-range suggestion. It likely became popular because it seems to be a golden middle for everyone. In fact, your body may need more or less water.
Factors that influence the amount of water you need
- Sex and age: At different ages, our body contains a different amount of water itself. Thus, it needs a different amount of it to stay hydrated. Different sexes also contain different amounts of water in the body.
- Weight: Studies say that adults with a higher body mass index are more likely to stay dehydrated. Also, besides keeping you adequately hydrated, water also may help you to lose weight.
- Environment: If you live in hot weather, you obviously need more water; and if you live near the sea or ocean, where humidity is higher, your organism would require less of it.
- Exercises: If you are an athlete or simply exercise regularly, you’ll sweat more than a person who has a stationary occupation. Thus, you have to substitute the fluid you lose.
Also, we can’t forget about special conditions, such as:
- Pregnancy and breastfeeding: During pregnancy, studies suggest that women should drink more water than usual.
- Overall health condition: Things like a fever or diarrhea make the body lose water faster than usual. It’s important to drink water to prevent dehydration.
How to calculate the amount of water you need

There’s a formula that will help you to calculate the amount of water your body needs:
- The amount of water in liters you need to drink per day is equal to your weight in kilograms multiplied by 0.033.
Once you calculate the amount, you can make a schedule that will help you to remember to drink as much water as you need. For example, it’s better to start your day with a glass or 2 of water on an empty stomach. Among other things, water in the morning increases your energy and speeds up your metabolism; thus, it will help you to stay well and cheerful all day long.
Note: As it was mentioned above, different conditions may influence this data, so it’s important to listen to what your body is telling you.
Products that can substitute water
Although experts suggest drinking pure water in order to get all the fluids you need, some people cannot drink that much water during the day.
People can substitute a part of their water intake with different fruits and vegetables that contain a lot of water. Watermelon, oranges, and cucumbers are made of more than 80% water. And different soups and drinks, like coffee or tea, may also replace several cups of water.
Did you know the exact amount of water you needed in a day? Is regular drinking a part of your routine? Let us know in the comments below.
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