Posted on May 30, 2018 by Josh Puttock

You may not know this, but your body is made up roughly of around 60% water. During daily activity we lose a lot of this water through urine and sweat. Think of water in your body like petrol in a car; if you don’t fuel up then you won’t be going anywhere.

So, it’s recommend you intake around eight ounces of water throughout the day to ensure you’re well hydrated and able to function properly. This equates to approximately two litres of water, which may seem a lot at first – but it really isn’t after a while.

Cognitive functions

It is often reported that cognitive (brain) functions and energy levels drop when we aren’t hydrated. Some studies show increases in mood swings and headaches in women for just a 1.3% reduction in water levels.

That may seem like a small number, however, 1% really is a lot. Other studies show that mild dehydration (loss between 1-3% bodyweight) caused by heat or exercise significantly impairs aspects of the brain.

Weight loss

Not only is water consumption important, it can also help you lose weight. A study showed that drinking 500ml of water boosts metabolism by 24-30%. The research further went into stating that the mentioned guideline can increase energy expenditure by 96 calories per day.

Drinking water can cause mild, temporary increases in metabolism and drinking it about a half hour before meals can actually make people automatically eat fewer calories.

Health problems

Several health problems can be helped through the intake of water. For example:

  • Constipation: Increasing water intake can help with constipation, which is a very common problem.
  • Cancer: There are some studies showing that those who drink more water have a lower risk of bladder and colorectal cancer, although other studies find no effect.
  • Kidney stones: Increased water intake appears to decrease the risk of kidney stones.
  • Acne and skin hydration: There are a lot of anecdotal reports on the internet about water helping to hydrate the skin and reducing acne.

Other beverages that you drink also contribute to fluid balance, including caffeinated drinks like coffee and tea. Most foods also contain water such as eggs, fish and meat.

Trust your thirst!

Maintaining water balance is essential for our survival. For this reason, evolution has provided us with intricate mechanisms for regulating when and how much we drink. Our innate regulatory response homeostasis tells our body when our total water content goes below a certain level, allowing thirst to kick in.

This is controlled by mechanisms similar to things like breathing; we don’t need to consciously think about it. For the majority of people, there probably isn’t any need to worry about water intake at all as the thirst instinct is very reliable and has managed to keep us humans alive for a very long time.

That being said, there are certain circumstances that may call for increased water intake. This includes exercise, as well as hot weather (especially in a dry climate). If you’re sweating a lot, make sure to replenish the lost fluid with water.

Athletes doing very long, intense exercises may also need to replenish electrolytes along with water. Most people don’t need to consciously think about water intake though, because the thirst mechanism in the brain is very effective. However, certain circumstances do call for increased intake.

How much water is best?

At the end of the day, no one can tell you exactly how much water you need. As with most things, this depends on the individual. Do some self-experimentation – some people may function better with more water than usual, while for others it only causes the inconvenience of more frequent trips to the bathroom.

That being said, life is complicated enough as it is so worrying about the over complexity of drinking water is just another stress. My word of advice is carry a water bottle with you everywhere. If you want to keep things simple (always a good idea), then these guidelines should apply to 90% of people:

  • When you’re thirsty, drink.
  • When you’re not thirsty anymore, stop.
  • During high heat and exercise, drink enough to compensate for the lost fluids.

These may seem basic, but they should cover you!

By Naweed Zaman, Gym & Spa Operator/Personal Trainer