The human body is made up of about 60% of water, and it is an essential element for all human life.

But we constantly lose it through our urine, sweat, bowel movements, as well as by eating heavily processed foods, stress, and breathing. In fact, we all lose about 2-3 liters of water a day.

This is why it is essential that the lost water is replenished in order to maintain a healthy normal balance in the body. Failure to do that can lead to dehydration.

How Much Water Should I Drink

We need enough water in order to help digest the food and move the nutrients through the body and to the cells, as well as for the kidneys to be able to filter and flush the toxins from our bodies. Water also cushions and lubricates our joints.

Without water, all of these functions will suffer. Mild dehydration can lead to a lack of energy. In severe cases of dehydration, a person can suffer from confusion, dizziness, and even have seizures.

So, obviously, it is important that we all drink enough water to stay healthy and to help our bodies function properly. But the question is – how much water should I drink?

There is no single clear-cut answer to this question. Many health authorities recommend that a person should drink eight glasses of 8-oz per day. This is about half a gallon or 2 liters of water. This is also known as the 8×8 rule and is easy to remember which makes it one of the most common answers to the question.

But, there are health experts who recommend that people should keep sipping a little water all day long, even when they are not really thirsty.

The fact is that we are all different, and everyone has a unique way and rate of water-loss and needs different quantities of it to replenish it and restore the balance.

Read on to find out more about how to decide how much water you should drink per day in order to stay well and healthy.

The many health benefits of water

Water is the main chemical component in the human body and is essential for our survival.

Each and every cell in our bodies, and each organ or tissue needs water to function properly.

We all need water in order to get rid of the toxins in our bodies through sweating, urination and bowel movements.

Water is also key to keeping our body temperature at normal levels.

It helps protect the sensitive tissues and is essential for cushioning and for lubricating the joints in our body.

Water also helps us digest the food we eat, move it through our digestive system, and extract and transport the nutrients to the different organs and body cells.

Which factors affect how much water we should drink?

Your personal daily water intake needs to be adjusted in accordance with these following factors:

  • The amount of exercise you get. The more you move and stay active, the more you will sweat, which means you will need more water to replenish this loss. If you go to the gym, run, or engage in any kind of activity which makes you sweat more profusely than usual, you should drink water prior to the activity.

In case the activity is very intense and lasts over an hour, then you can drink sports drinks with electrolytes which can help replace the lost minerals in the body from the sweating.

  • The climate you live in. When the weather is hot and humid, you sweat more, which means that you need more water to stay hydrated.
  • The altitude you are at. Living or walking at high altitudes also leads to faster dehydration, which is why you should drink more water if you go hiking or mountaineering.
  • Your overall health. When you are sick and have a fever, or suffer from diarrhea or vomiting, you lose more water than normal. This is why people should drink more water and liquids when they are ill. Some other underlying health conditions may also require an increased intake of water, including urinary tract stones or bladder infections.
  • Pregnancy and nursing. Women who are pregnant or breastfeeding need more water and fluids to stay hydrated because a lot of their water gets transferred to the fetus or the baby through the placenta and through breast milk. This is why it is recommended that women who are breastfeeding or are pregnant should increase their daily water intake to up to 10 to 13 cups.

Can water intake affect our cognitive function and energy levels?

There are many studies that have found that dehydration can lead to lowered energy levels and can lea dot a negative effect on the function of the brain.

One study found that a loss of just 1.36% of water from exercise can impair concentration and mood, and increases the risk of headaches.

Another study found that mild dehydration with a loss of 1-3% of the bodyweight following exercise or in hot and humid conditions can harm the cognitive and brain function in many aspects.

Mild dehydration can also lead to reduced endurance levels.

What about the 8×8 rule?

Drinking eight 8-oz cups of water a day is something which probably everybody has heard. It is a reasonable piece of advice and is easy to remember.

But the fact is, most healthy people can stay properly hydrated if they drink water or other fluids only when they feel thirsty.

The truth is, this universal 8×8 rule may be too much for some and too little for others.

The exact quantity of water you need to stay healthy and properly hydrated depends on the climate you live in, your activity level, your overall health, and other individual factors.

The Food And Nutrition Board of the Health and Medicine Division of the National Academies of Science Engineering and Medicine, recommends an intake of approximately 91-oz (2.7 liters) of total water for women per day (from food and liquids), and about 3.7 liters, or 125-oz a day for men.

The average daily intake of water is about 80% from water and other beverages, and 20% is from foods containing water.

Pregnant and nursing women need to increase their daily water intake.

Does drinking more water promote weight loss?

There have been claims and studies showing that increased water intake can help boost the metabolism, reduce the appetite, and thus promote weight loss.

Two studies have found that drinking 500ml (17-oz) of water boosts the human metabolism temporarily by 24-30%.

Another study found that drinking 2 liters (68-oz) of water a day helped burn 96 calories per day.

There are additional claims that drinking colder water can help burn more calories because the human body needs more energy to heat it up to body temperature.

Other studies have found that drinking water about half an hour before each meal can help reduce the number of calories you eat, especially in older people.

A specific study found that the subjects who drank 500ml (17-oz) of water 03 minutes before each meal lost 44% more weight than the other dieters who didn’t drink it prior to meals, over a period of 12 weeks.

In conclusion, we must say that drinking sufficient amounts of water before meals, when combined with a healthy diet can promote faster weight loss, because it decreases the caloric intake, and also boosts the metabolism, as well as burns calories.

Can drinking more water protect us from health problems?

There are studies that have found that increased water intake can help reduce the risk of certain health problems.

One of them is resolving problems with constipation.

Other studies show that people who drink more water are at lower risk of developing colorectal and bladder cancer. But there are separate studies that have found no such correlation.

Research has found that an increased intake of water can help reduce the risk of developing kidney stones.

Increased water intake also has been claimed to help keep the skin hydrated and reduce the instances of acne, although there is no scientific proof of this claim so far.

Do the other beverages and fluids you drink add to the total water intake?

Although drinking plain water is the easiest and best way to stay hydrated, we get about 20% of the water we need from the foods we eat and even larger percentages from the other beverages we consume every day.

Even though there are claims that caffeinated beverages do not count as part of the total water intake because of their diuretic effect, there are multiple studies that refute this claim and have found that tea and caffeinated drinks are actually pretty weak diuretics.

A lot of the food we eat is rich in water. Vegetables, fruits, as well as meat, fish, and eggs are some of the foods which are loaded with water.

So, if you eat a lot of veggies, fruits, and drink tea and coffee or other caffeinated drinks, you can count them as part of the total water intake as well.

So, what counts as water, and what doesn’t?

As mentioned above, some foods are loaded with water. Keep in mind that plant foods like watermelons, cucumbers, celery, lettuce, or spinach are more than 90% made of water.

Also, beverages like juice, milk, and herbal teas are also high in water content. So are caffeinated beverages like coffee or soda, which too contribute to your daily water intake.

Sports drinks are recommended for use only during and after vigorous exercise of over an hour. They help replenish the electrolytes and minerals lost through the sweat, and also provide the body with the sugar and carbohydrates it needs for fuel during the exercise.

Energy drinks are very different from sports drinks. They are not made to replace electrolytes, and usually contain stimulants like caffeine or others, as well as a lot of other additives and sugar.

Juices, smoothies, and sodas are hydrating but are also usually much more caloric and contain sugar.

Coffee and tea also provide water, so you can drink them throughout the day, as long as the caffeine doesn’t make you jittery.

Alcoholic beverages also contain water, but they do act like diuretics and actually promote more water loss through urination.

Overall, plain water is the cheapest and healthiest, calorie-free way to replenish the water you lose throughout the day.

You should be careful about the sugar, the caloric values and other ingredients in the other beverages mentioned above if you want to stay healthy. So, look at the labels and limit your consumption of sugary or high-calorie drinks.

Alcohol too can lead to dehydration when consumed in excessive amounts.

Can drinking too much water harm me?

Hypernatremia or an excessive amount of water in the body is a rare occurrence for people living healthy and normal lives in developed countries.

Hypernatremia is caused by too much water in the body which dilutes the minerals in the blood. This leads to a drop in the sodium levels in the blood.

In severe cases of hypernatremia, the cells of the body may swell and can lead to serious and even life-threatening problems.

Marathon runners and other endurance athletes are at a higher risk of suffering from drinking unhealthy amounts of water.

Also, some health conditions may require that you lower your water intake, including heart failure and some types of kidney disease. You should also speak to your doctor about the recommended water intake if you suffer from thyroid disease, have liver problems or take meds which make the body hold water.

Listen to your body to find out when you need more water

The feeling of thirst is actually a very sophisticated system that helps people regulate the amount of water they drink.

The feeling of thirst appears when the water level in the body decreases. This is why, you should pay attention to thirst, and drink water or other beverages when you get it.

For most people, the thirst instinct works as a perfect regulator for maintaining a healthy balance of water in their bodies.

Unfortunately, the instinctive thirst mechanism can begin malfunctioning as people age, which is why older people should monitor their water intake more closely to ensure that they remain properly hydrated.

How much water should children drink?

The amount of water which a kid should drink depends on a number of different factors, including its age, weight, its gender, its activity level, and its health. It also depends on the climate and the season.

But on average, the recommended amount of water for children and teenagers per day is 6-8 cups of water. You should ensure that they get sufficient amounts of fresh fruits and vegetables which are rich in water, and in vitamins, minerals, and other essential nutrients.

When kids are playing or exercising, a good goal to follow is to stop to drink ½-3 cups of water every 15-20 minutes.

So, how much water should I drink after all?

As you can see from this article there is no simple answer to this question. It actually depends on every individual person.

Some people function better with more water intake than others, so you should experiment and see what amount works best for your energy levels, brain function and mood.

A good rule of the thumb is that you are getting sufficient amounts of water if you:

  • Don’t or rarely feel thirsty
  • Your urine is light yellow or colorless in color

You can also drink water when you feel hungry because many people confuse the two feelings.

You should drink water before exercising or before strenuous activities.

When participating in longer exercise sessions, you need to stay hydrated and may want to replenish the lost salts and minerals with sports drinks after an hour of exercise.

Keep in mind, that when running a marathon or participating in another endurance event, you can be at a higher risk of drinking too much water which can lead to the dilution of sodium in the blood, and can lead to severe and even life-threatening problems.

At the same time, severe dehydration can also lead to serious and even life-threatening problems and conditions, so it is essential that you monitor your water intake very closely if you participate in such endurance events, vigorous and long exercise sessions, if you are a hiker or mountain climber, and an overall active person.

Women who are breastfeeding or pregnant need more water. And so do people suffering from certain health conditions, or those who have diarrhea, vomiting or fever. If you feel stressed, you should also drink more water.

Drinking more water before meals can even help promote weight loss.

When it is hot and humid outside – remember to drink more water too.

Also, of course, when you feel thirsty – drink water, and when you stop being thirsty – stop drinking it!


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