Why Is Hydration So Important?

Why Is Hydration So Important?

We all know that drinking water is important for our general health and wellbeing, but do we know why? The media may routinely tell us how much water to drink each day, but what exactly does water do in the body? Just as importantly, what are the consequences of not drinking enough water?

This article will answer these questions and give you an idea of how much water you should be aiming to drink on a daily basis. Hopefully this will give all those people constantly reminding you to hydrate some context…

The Human Body and Water

The average adult human body is 50-65% water and every cell, tissue and organ in your body requires water in order to function at its best. Water is used in so many processes around the body: maintaining the body's temperature, removing waste, transportation of nutrients to cells and keeping joints lubricated, to name but a few uses. Water is pretty essential to our everyday lives – you simply wouldn’t survive without it.

The vast majority of people do not consume enough water daily however, which means the water we lose isn’t being replaced after things like sweating and urinating (did you know that there’s even water in your breath, which also needs replacing?). This is what leads to dehydration, and even doing very little physical activity causes water to pass through your system.

Naturally, exercise and hot days speed up the dehydration process. If you’re looking to stay perfectly hydrated after exercise, weigh yourself before and after to complete your workout – for every kilogram lost, replace it with one and a half litres of water.

Symptoms of Dehydration

Dehydration is almost an instinctual condition, but there’s a few noticeable symptoms that go along with it. Some of the more straightforward symptoms include a dry mouth and an extreme thirst. What a lot of people don’t realise it that dehydration can have an effect on the mind: confusion and dizziness, even sleepiness are effects of dehydration. One especially painful symptom is headaches – if your mind is ‘cloudy’ and painful, try upping the amount of water you drink.

If you feel you may be getting dehydrated, it's important not to wait until symptoms appear and try to keep well hydrated throughout the day, especially if it's hot. If you feel the symptoms of dehydration coming on, take action and drink plenty of water to boost your hydration levels and stay healthy and active.

Why Does Dehydration Occur?

Dehydration is a sign that your body, organs, cells and tissues need more water to function properly. When the weather is hot, we lose more water via sweating so it's very important to stay hydrated and drink plenty of fluids particularly during the summer months.

Exercise can also lead to dehydration as we sweat more when exercising. Sweat also contains electrolytes – trace elements like potassium, calcium and magnesium – which gives sweat its salty taste. This is why sports drinks will constantly mention these in their marketing; it’s important for athletes to maintain a high level of electrolytes as they’re crucial in muscle function.

As we get older, we may also be at a higher risk of dehydration as the brain may not be able to sense dehydration signs as easily. Certain medical conditions such as kidney stones and infections can also increase our risk of dehydration, as can being pregnant and having a fever.

Certain conditions will also require a person hydrate more throughout the day. Illnesses that have diarrhoea or vomiting symptoms will need the water lost from those processes replaced. Also, diabetes can lead to greater fluid loss, as high blood sugar levels cause the kidneys to attempt to lower them via urination. Take extra care of your hydration levels if you have conditions similar to these.

How Much Water Should We Drink?

Current recommended daily water limits vary but many people aim to drink 2.5 litres of water a day, which is a reasonable goal for most people. As with everything however, different people need different amounts of water. For example, an athlete exercising in the heat will need far more water to stay hydrated than say an inactive person in the winter. That 2.5 litre amount also takes into account the water contained in food too, which accounts for about 20-30% of your intake.

Most people can stay well hydrated by simply drinking when they are thirsty. Others, such as elite athletes or those with conditions mentioned earlier, may need to drink more to keep up with the higher amount of water they’re cycling through their body.

Checking your urine can be a good indicator of hydration levels; if your urine is colourless or light yellow, you know that your body is well-hydrated. If your urine is dark yellow or amber coloured however, it may be time to drink a bit more water as this can be a sign of dehydration. This is why urine is darker in the morning, as your body has low hydration after waking up.

Tips for Staying Hydrated

Drinking water throughout the day may be something that can slip your mind, particularly if you are busy. Here are a few handy tips for keeping well hydrated throughout the day.

  • Keep a bottle of water with you throughout the day that can be easily refilled if necessary. Purchasing water constantly can be expensive as well as creating plastic bottle waste, so invest in a reusable bottle and fill from a tap or drinking fountain. Some even come have time markers on them, advising you on how how much you should be drinking per hour.
  • If you aren't a fan of plain old tap water try spicing it up with some fruits such as lemon or strawberries to give a bit of flavour. Try to avoid soft drinks, as many contain a huge amount of sugar per serving.
  • Always drink water before, during and after exercise. Don’t drink too much at one time, though, as it can lead to feelings of nausea – little and often is the key.
  • Feeling hungry? Drink water. Thirst can often be confused with hunger so drinking plenty of water can also be beneficial for those looking to control their weight.


It can feel like there’s so much pressure to keep yourself hydrated, but it’s for a good reason: water is the most important thing for your body. It’s used in literally every cell in your body and is necessary for so many processes around the body. It’s easy to stay hydrated throughout the day, too; all it requires is a nice big water bottle and a little extra vigilance.

Staying hydrated can also help you feel healthier in general too, with the mind and skin being two places that can see big impacts from a little extra water a day. No matter your age, your level of activity or temperature where you live, it’s always good to have an extra glass of water. Remember: make sure your urine is pale, keep a full bottle with you whenever you leave the house and drink even when you’re not feeling thirsty.