How Much Water Should You Drink Per Day

How Much Water Should You Drink Per Day

Water is the most plentiful substance in the human body and can account for over 65% of your cells. With every bodily system depending on it, water is essential for life.

Water is required in digestion and absorption of food, circulation of oxygen and nutrients, thermoregulation, metabolism, detoxification and removal of wastes, humidifying the air in your lungs, lubricating and moisturizing your joints and even protecting some vital organs. Your brain is made up of about 90% water, your muscles 75%, and your blood 80%. It is absolutely vital to your health.

You are constantly losing water through certain processes such as breathing, perspiration and excretion. An adult excretes an average of 1.5 liters a day and can lose anywhere from 0.1- 2.5 liters a day in sweat, depending on the climate and exercise intensity. This water must be regularly replenished if we are to function optimally.

But do you know how much you should be consuming per day?

The amount of water you need to drink each day can vary depending on a number of factors. These factors include; gender, bodyweight, general level of health, climate and activity level.

We have all heard the advice of drinking eight 8oz glasses of water every day, but there is no real scientific evidence to back it up. The Institute of Medicine recommends that men consume approximately 3 liters of fluid per day and women approximately 2.5 liters. The key factor is that this, includes all fluids, not just water.

Since we get approximately 20% of our daily fluid intake from foods, and a certain amount from other fluids such as milk, tea, juice, sports drinks, etc. the eight 8oz glasses of water per day rule is not that far off.

It is generally recommended that you constantly sip water throughout the day so as that you rarely feel thirsty and your urine is colorless or slightly yellow. Lack of adequate water or fluids can lead to dehydration, which can become extremely dangerous and even fatal. Signs of dehydration include headache, light-headedness, thirst and/or dry mouth, confusion and tiredness.

So is there a danger with drinking too much water?

Yes, water intoxication or poisoning although very rare can occur, and just like dehydration, can be extremely dangerous and even fatal. Drinking too much water can upset the delicate electrolyte balance in the body resulting in a condition called Hyponatraemia. It is not how much you drink but how fast you drink that is the more important factor when it comes to Hyponatraemia. Drinking a lot of water over time allows for excretion, but drinking a very large volume at one time is when the danger can occur.

So the take home message is if you are following the old advice of drinking eight 8oz glasses of water a day you are on the right track. Some times you may need a few extra glasses especially when you exercise or sweat a lot and be careful to not only replenish the loss fluid but also the lost electrolytes.


Vancouver Health Coach