Amazingly we can live for no more than 5 days without water as opposed to 30–40 days without food (2). Yet many of us don't drink enough of this precious liquid. Most of us live in a state of mild to moderate dehydration and don't even realise it.
A recent patient of mine who is a plumber and works long hours outdoors was always suffering from muscle cramps and headaches. When I asked him how much water he drank per day he said the recommended 2–3L. But when we undertook some general blood tests his results indicated that he was suffering from a state of dehydration with an alteration in his kidney function. I advised him to trial doubling his water intake. Within a matter of days his symptoms had improved. I recently saw him again and he mentioned that his symptoms have abated just by making sure he is drinking plenty of water to compensate his losses through sweat.
So what are some of the signs and symptoms that you may be suffering from dehydration? Some of these may surprise you!
Signs That You Are DehydratedFatigue (3)Headaches (3)Reduced concentration (4)Dark circles under the eyes (3)Muscle cramps (5)Dry skinJoint pains (4)Dry, sticky mouth (late symptom)(3)Constipation (3)Dizziness or light-headedness (3)Inability to lose weight (4)Digestion problems (4)Decreased urine output (passing urine less than 4 times per day) (3)Dark-coloured urine (6)
Given these symptoms, how much water should we be drinking?
How Much Water Do You Need?
Although research isn't clear on exactly how much water to drink per day the general recommendation is 2–3L per day or 6–8 glasses (6). I generally make a more specific recommendation and say drink 1L for every 25kg that you weigh.
Keep in mind, however, that if you are engaging in heavy exercise or are sweating heavily then you need to add an extra 1–1.5L for every hour of heavy exercise or heavy sweating (7).
You know that you have drunk enough water throughout the day if your urine is straw-coloured or clear.
Too Much of a Good Thing?
Sometimes when I am presenting a workshop on the importance of staying hydrated I am asked if it is possible to drink too much water. The answer is yes, you can have too much of a good thing.
There exists a psychological condition called psychogenic polydipsia where individuals are compelled to drink excessive amounts of water - sometimes reaching up to 20L per day. At this level the body's electrolytes are diluted so much that there is a risk of seizures and brain swelling (7). So you can drink too much water but, in reality, many of us are unable to drink the amount needed to be harmful. If you stick to the recommended quota you will be well within safe limits.
Homemade Electrolyte Solution (8)1 L water1⁄2 level tsp salt6 level tsps dextrose powder
What About Electrolytes?
I am often asked whether it is important to supplement drinking water with electrolytes.
The current research suggests that this is only important if you are undertaking heavy exercise for about 60 minutes or more or are sweating profusely (7). In this case adding a few scoops of electrolyte solution to plain water is reasonable, or make your own by using the formula here.
For the everyday individual who works indoors and undertakes light to moderate amounts of exercise plain water is the best option.
What If You Do Not Like Water?
Every now and then I meet individuals who do not like drinking water because they find it too bland. This is often the case if someone's taste buds are used to sweet or caffeinated drinks. As mentioned earlier in this book our bodies really only want what they are used to. If you are used to drinking anything but plain water that is what your body will crave.
As a personal example I remember a time when I used to drink diet cordial instead of water all day long. I was addicted to the taste and couldn't stand to drink plain water. When I came to the realisation that all that cordial was not good for my body and that I needed to switch to plain water I had a real mental challenge on my hands. I had to re-train my taste buds to crave plain water -, which took me around a month to do. Now I can't imagine drinking anything other than plain water. My tastebuds have adjusted.
So what I say to individuals who are in the same situation is to keep at it. Continue drinking plain water until you are able to re-train your taste buds.
Some healthy additions to water are sparkling mineral water with lemon or lime juice or even some ginger and mint. On the topic of mineral water, some people find that they suffer from bloating and indigestion from drinking carbonated water - that is often because the water has been artificially carbonated rather than carbonated via a natural process. In this case try drinking naturally carbonated water such as Vittoria or San Pellegrino.
To Filter or Not to Filter?
To date there is no absolute evidence pointing to the benefits of filtered or bottled water over tap water in developed countries. Saying that, there is some preliminary evidence to suggest that the amount of chlorine and fluoride added to our water-purifying systems is harmful to our health and can be attributing to a number of health problems ranging from cancer and allergies to abdominal pains and headaches (4).
Tank water is prone to being contaminated with bacteria and other organisms (9). I recall a patient who came to see me to seek help for abdominal pains and diarrhoea of three months duration. When we undertook stool testing she in fact had a parasite infection called cryptosporidium from drinking contaminated water. Tank water must be regularly checked to ensure it is not contaminated.
If you want to ensure that the water you are drinking is uncontaminated the best filtration system is reverse osmosis4. Make sure you purchase this from a reputable source. Many people choose to have a reverse osmosis filtration system installed under the sink.
There is some evidence to suggest that choosing to add an alkaline filter to your system replenishes essential minerals in the body (4). As an alternative to alkaline filters you can add a few drops of alkaline solution to each glass of water. Alkaline solution can be bought from most health food stores. Often bottled water is actually tap water filtered in this way and not 'bottled at the source' as marketing would have you believe.
Chilled, Warm or Room Temperature?
This is another common query. Should our water be drunk at room temperature, slightly warmed or drunk cold? The theory behind drinking warm water or room temperature over chilled is that chilled water is too much of a 'shock' to our body, which typically sits at around 37 degrees. To date, however, there is no supporting evidence to suggest warm is better than chilled. In reality, most of us are able to drink more water if it is at room temperature simply because chilled water is often too cold to drink at once.
Should You Wait Until You Are Thirsty?
By the time we actually feel thirsty we are already dehydrated. This is due to the delay in response from brain osmoreceptors - an area of brain tissue that literally detects when we are running low on water. The best approach is to be proactive about drinking water and to drink it regularly throughout the day.
Drinking your entire water intake at the end of the day because you have realised you haven't drunk enough unfortunately won't be of much benefit. This is because the body filters water at a certain rate, leading you to pass the excess water as urine. Waiting till the end of the day will most likely lead to disturbed sleep when you have to keep getting up to go to the bathroom! A better approach is to pace yourself and drink a glass or about 200 mL every 1.5–2 hours. If you find that you have to go to the bathroom more than once throughout the night try limiting fluids three hours before bed.
Lastly, an interesting phenomenon occurs when we become dehydrated. Our body confuses thirst with hunger. So the next time you are feeling hungry try drinking a glass of water to see if your appetite can be curbed.
Strategies to Increase Your Water Intake
Some ways to ensure adequate water intake are:Take a large 1L water bottle to work and ensure you refill it at least once.Keep a jug of water on your desk and drink a glass every 1.5–2 hours.Choose water over juice or soft drinks at lunch.Choose sparkling mineral water at restaurants rather than another glass of wine.Add a little lemon/lime juice and mint to water for flavour.
Take Home Points
You need water to survive and thrive.You need on average 2–3L of water a day or about 1L for every 25kg that we weigh.You know you have drunk enough when your urine is straw-coloured or clear.Dehydration can occur even when you are not thirsty. The most common signs and symptoms are fatigue, headaches, muscle cramps, constipation and light-headedness.Only add electrolytes to your water if you are undertaking heavy exercise for at least an hour.Our body tends to want what we normally give it. Over time, with consistent water drinking, our bodies will learn to love this vital liquid.If you choose to filter your water the best water filtration system is reverse osmosis with or without an alkaline filter.You can often drink more water if it is at room temperature.Try to drink consistently throughout the day by always keeping a bottle or jug filled with water near by.
Your Weekly Challenge
This week your challenge is to increase your water consumption to 6–8 glasses a day or 2–3L. If you are not used to drinking this much water, start by adding one extra glass a day until you build up to the recommended amount. Remember to spread out your water drinking throughout the day.