Why Does Your Body Need Water?

Why does your body need water?

Water is essential for life and normal body function.

Every part of the body depends on water. It is present in body fluids, cells, tissues, and organs and helps support many processes that happen throughout the day.

Unlike protein, carbohydrates, and fat, water does not provide calories. Its role is different, but it is just as important to overall nutrition.

What does water do in the body?

Water has many important functions.

It helps your body:

• maintain a normal body temperature
• lubricate and cushion joints
• protect sensitive tissues
• support normal digestion
• remove waste through urination, perspiration, and bowel movements
• maintain normal fluid balance

Water is also the basis of many of the fluids found throughout the body.

How does your body lose water?

Your body is constantly losing water.

Water is lost through:

• breathing
• sweating
• urination
• bowel movements

You may lose more water when you:

• exercise
• spend time in hot weather
• have a fever
• have vomiting or diarrhea
• sweat more than usual

Because water is continually being lost, it also needs to be continually replaced.

Where does your daily water come from?

Your daily water does not come only from glasses of plain water.

Water can come from:

• drinking water
• milk
• tea and coffee
• soups
• other beverages
• fruits
• vegetables
• other foods containing water

Foods with a high water content can make a meaningful contribution to total daily water intake.

This is why total water intake and the amount of plain water you drink are not exactly the same thing.

Do other drinks count toward hydration?

Yes.

Many beverages contribute water to your daily intake.

Plain water is a useful choice because it provides hydration without calories or added sugar, but it is not the only source of water in the diet.

Milk, tea, coffee, and other beverages also contribute fluid.

Some drinks can also contain calories, added sugars, caffeine, or other nutrients, so the overall nutrition of the beverage still matters.

What is dehydration?

Dehydration happens when your body loses more fluid than it takes in and does not have enough fluid to function properly.

It can happen when you:

• do not drink enough fluids
• sweat heavily
• have vomiting or diarrhea
• have a fever
• lose more fluid than usual for another reason

The risk can increase during hot weather or physical activity because the body may lose more water through sweating.

Severe dehydration can be a medical emergency.

How much water do you need?

There is no single amount of water that is right for everyone.

Water needs can vary according to factors such as:

• age
• sex
• body size
• physical activity
• climate
• pregnancy
• breastfeeding
• health status
• foods and beverages consumed

MedlinePlus cites general adult total-water reference intakes of about 2.7 to 3.7 liters per day.

Importantly, this refers to total water from both foods and beverages, not only plain drinking water.

Individual needs can be higher or lower depending on the person and circumstances.

Eat Ate Here can help you track water as part of your daily nutrition, but it does not replace individualized advice from a qualified healthcare professional.

Do you need eight glasses of water every day?

Not necessarily.

“Eight glasses a day” is a simple rule that is often repeated, but water needs are not identical for every person.

The amount you need depends on your total diet, activity, environment, body, and health.

It is therefore more useful to think about overall hydration and total water intake than to treat one fixed number of glasses as a universal requirement.

Does food contribute to hydration?

Yes.

Food can contribute a meaningful amount of water to your daily intake.

Foods that naturally contain a lot of water include many:

• fruits
• vegetables
• soups
• dairy foods

This means two people could drink different amounts of plain water while still having similar total water intake depending on the foods and other beverages they consume.

How does water fit into overall nutrition?

Water is one of Eat Ate Here’s seven core nutrition areas.

The seven areas are:

• protein
• carbohydrates
• water
• total fat
• fiber
• vitamins
• minerals

Calories are tracked separately as energy.

Water is different from most other nutrients because it does not provide calories, but it remains essential for normal body function.

That is why Eat Ate Here tracks water alongside the other major parts of daily nutrition.

Practical takeaway

Water is essential for normal body function and needs to be replaced as your body loses it throughout the day.

Your total water can come from plain water, other beverages, and foods.

Rather than focusing on one universal number of glasses, consider your total intake and the factors that can change your personal hydration needs, including activity, climate, diet, and health.