Water - it’s everywhere. The sea, the sky and in ourselves. We all know that it plays one of the most important parts in looking after our bodies, but do you really know why? What role does it actually play? It’s one of the main components of both the planet and our bodies, and staying hydrated has a number of health benefits - ranging from maintaining a normal bodily function to anti-ageing and weight loss!
Before we begin, it’s important to take a look at water itself and what it does in the body…
Back to the classroom…
Water is a compound made up of Hydrogen and Oxygen and is one of the staple elements. Water (H20) is composed of two hydrogen molecules covalently bonded to one Oxygen molecule. Water is the most abundant molecule on Earth, making up 70% of the Earths surface, and more importantly, between 50-75% of our bodies. . It makes up our cells (around 66% of the bodies total water content is found inside of the cells) and all bodily tissues- and is found as the primary substance in Plasma, which makes up 55% of our blood.  It serves a number of vital functions in the body, including:
Water enables metabolic hydrolysis reactions to take place. A hydrolysis reaction is where a water molecule is broken down and is bonded to another molecule. This happens in various parts of the body for many different reactions and purposes. Other metabolic reactions can also produce water molecules, and on average the body will produce between 250-350ml of water a day. 
Body Temperature Regulation
Water regulates the bodies internal temperature. Sweating is an important way to cool down, and prevents the body from overheating (which can denature important bodily cells and affect their ability to function). Sweating allows the body to cool and thermoregulate by losing calories in the form of heat. The loss of energy decreases our internal temperature.
Transport of Nutrients for Cell Function
Water transports nutritional elements to cells around the body, through the movement of nutrients across cell membranes and capillary beds. It is an essential process as the cells need certain nutrients to function properly. Nutrients such as amino acids, protein and lipids are passed into cells, as well as other minerals and trace elements. Water acts as a solvent for glucose, which is essential for cell functioning.
Removal of Waste
Water plays an active part in removing waste produced by cells in the body. The cells in our body produce waste which can be harmful to the body if not efficiently removed - such as urea, creatine and ammonia. All of these toxic chemicals are moved by water in the body and expelled in the urine.
How much should you aim for?
Experts recommend aiming for between 8-10 glasses a day, but obviously, this varies from person to person. On average everyone should aim for at least 2 litres. The US Institute of Medicine has determined that the general consumption for men should be around 3 litres (13 cups), and women around 2.2 litres (9 cups). 
It sounds a lot worse than it is. On average, we’re awake for 15 hours per day.  That’s less than a cup an hour!
The average adult human body contains between 35-45l of water , however on average, the body will lose between 1-1.5l of that in a day - even more so after undertaking a strenuous activity. It’s lost through sweating, urine output and through respiration, and therefore it’s important to replace what’s lost as a minimum.
What are the benefits of drinking water?
Drinking water has endless benefits. It makes up most of who we are and makes up 78%  of our brains so, in order to maintain mental alertness, hydration is crucial.
Lack of water is the main cause of daytime fatigue - a mere 2% drop in bodily water levels can cause disrupted short-term memory and difficulty focusing, and drop energy levels by around 20%. By staying hydrated and drinking a lot of water you’re able to keep your mental attitude sharp and keep focused on the task at hand. Drinking water boosts productivity and morale by turning your focus and allowing you to concentrate, and keeping your energy elevated during the day. In a recent study conducted by the University of East London, basic mental function tests were carried out on participants who had abstained from water, and then again after they had drunk a bottle of water. The results show that the consumption of water made the participants up to 14% faster than they were when they had abstained from drinking water. 
Weight Loss and Satiety
Of course, it’s better to drink water rather than high sugar, high-calorie fizzy drinks. However, proper hydration is also beneficial for weight loss in other ways. By drinking before meal time, various studies have found a suppression of appetite and reduced feelings of hunger. In 2015, the University of Birmingham conducted a small study to assess the effect of water on hunger and weight management. They found that on average, people who drank a glass of water 30 minutes before their meal times lost between 5-9lbs over the course of three months. The researchers concluded that the unintentional deduction in the participants' calories is due to the full-feeling that was given by drinking the glass of water.  With the energy and mood boost you get from being hydrated, you’re more likely to be motivated to engage in exercise, as well as have more stamina when you do.
Drinking water with or after a meal naturally aids digestion. It helps the body to break down foods in the stomach, reducing gastric discomfort. It is thought that water also helps to flush waste from the intestines, and helps to prevent and also relieve constipation by replacing the water which was lost and keep the stools hydrated, making them easier to pass.
Modern myth has it that good hydration is the miracle cure for the skin - from acne through to ageing skin, and everything in between. Although it may not produce instant results, a lot of people swear by it. The skin contains up to 30% water, and therefore in order to keep it looking plump, you need to stay hydrated. There haven’t been many studies conducted looking at the effect of water on the skin as there are minimal financial benefits from the results - however one study has shown that after four weeks of drinking mineral water, participants showed a decrease in skin density but an increase in skin thickness which is linked to the skin retaining more moisture . Once the cells are correctly hydrated, they start being more productive which in turn gives you healthier skin which: rejuvenates and repairs quickly, which retains moisture and retains its elasticity.
Mental Health Benefits
There is a link between bodily water levels and the level of serotonin in the brain. Tryptophan is an amino acid which is converted into serotonin, and it needs a large amount of water in the system in order to be transported across the blood-brain barrier.  Serotonin is responsible for affecting a number of behaviours and feelings - affecting mood, social behaviours, sleep, appetite, sexual desire and digestion.  Insufficient levels of serotonin can cause a depletion in the mood, and are linked with depression and anxiety disorders. By increasing the amount of water you consume, tryptophan will pass the blood-brain barrier with no issues and be converted into serotonin.
What can happen if we don’t get enough water?
Dehydration is the imbalance of water intake and water loss and occurs when more water has been lost than what has been consumed. Mild dehydration and occur simply from not drinking enough, however, some cases are a lot more serious and can be caused by the onset of an illness. Illnesses such as diarrhoea and vomiting can cause dehydration due to the quick explosion of bodily fluids.
Mild dehydration can affect both mental and physical performance. It can make you feel tired and lethargic, give you a headache, decreased urine output and a darkening in urine colour, muscle weakness, inability to focus, and a dry mouth. Severe dehydration is a serious problem and if left untreated can be fatal. It can lower the blood pressure, speed up the heart rate and breathing, cause severe confusion and eventually unconsciousness. 
A lack of water can also increase your risk of developing kidney stones. A low urine volume means that the salts and toxic chemicals are of a higher concentration in the urine, and are more likely to solidify in the urinary tracts causing kidney stones.
How to increase your water intake:
First of all, there are a lot of foods which have a high water content. These include the likes of:
- Cucumber (96% water)
- Lettuce (96% water)
- Celery (95% water)
- Watermelon (92% water)
- Strawberries (92% water)
- Grapefruit (91% water)
- Pineapple (87% water)
- Oranges (87% water)
Plus many others. A 2009 study conducted at the University of Aberdeen claims that eating watermelon or cucumber after a workout may hydrate your body up to two times quicker than a glass of water due to the natural sugars, amino acids and minerals in them which replace what was lost during the exercise. 
Removing the temptation of sugary drinks may also be helpful as you’re more likely to opt for a glass of water, rather than picking up a can from the fridge.
And of course, there are many ways to jazz up your water if you just can’t stomach 8-10 glasses of the tasteless liquid. Sparkling water is a good alternative and also great for getting kids to drink up as the bubbles make it more interesting. Similarly, adding fruit slices or fruity ice cubes to your water may also help. Lemon and lime water is a very easy and changes the taste completely! This will help you get some of the benefits of the fruit you use as well.
Don’t wait until you’re thirsty, instead, try sipping small amounts at regular intervals throughout the day and alongside meals as this helps the body retain more of what you consume so it won’t just be passed straight out.
Try swapping your sugary, caffeine rich drinks for use herbal teas with little caffeine, decaffeinated coffee, flavoured water and squashes, however, you do have to watch out for added sugars.  Bear in mind that, while these drinks are all still ways of getting water - they might not be as healthy for you as just plain water. A lot of squashes and flavoured water will have added sugar, and this is something to be wary of.
And if temptation gets too much, try alternating drinks. For every cup of coffee or alcohol, make the next glass a glass of water. This way you’re not missing out, yet you’re still getting your intake of water.
Without food, we’d last about 3 weeks. But without water, we’d last approximately three days. Water is a vital part of our everyday life and functioning - and aids in keeping us youthful and healthy. The best part is? It’s natural and inexpensive. Whether it’s bottled, or safe tap water, there are a lot of benefits that come with being properly hydrated. It’s so important to keep your body functioning properly, and even better when there are more benefits for the more you consume!
Is water enough?
To function properly, our bodies not only need water, but our blood must maintain a good electrolyte balance, to stay hydrated. Sodium and potassium are essential for this, along with magnesium, which helps to preserve potassium stores. Beetroot provides potassium, nitrates and magnesium, so can support hydration within the body.
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 Essentials of Human Nutrition (Fourth Edition)- Mann Trustwell written for Oxford