I’m sure you saw in the news today, oh boy, that Dr Margaret McCartney GP, has written a piece for the comment section in the British Medical Journal, about the futility of drinking large amounts of water and that the risk and consequences of dehydration are often overstated, amongst other spurious claims. As usual, we have Tweedle-dee on one side saying ‘‘tis’, and Tweedle-dum on the other saying ‘‘tisn’t’. The argument and opinions of both sides are not only confusing to the public, but I feel are confused themselves.
Lets have a look at, in all likelihood, the reason we (Humans) are here, that being simple water.
Every living creature on earth is mostly made of water. The saying ‘dry as a bone’ comes to mind, ‘dry’? not a chance, even your bones are a quarter water. The rest of the tissues that make you, have even higher water contents: Blood 82%; Muscles 70%; Brain 75%. Pretty much all of the chemistry that allows you to ‘be’, requires water to take place. Therefore, the most important substance in your body is water. Pure and simple, um…not quite, but we’ll get to that.
The quality of your bodily tissues, their ability to function and resist or repair damage, is almost entirely dependent on the quality of the water you consume. Quality water, however, is not so easy to find.
In the UK most of us get our drinking water either from the tap or as bottled water, we’ll come back to this in a minute. A minority of people still get their water from a well or a fresh spring, in fact one of my closest friends is very proud of the fact that his tap water is directly fed by the local spring, and he claims is as ‘pure as pure can be’. Not quite.
Although it hasn’t been put through a treatment system that may use aluminium or chloride as agents, this does not necessarily make it ‘pure’. Since well, or spring water, comes either from ground or surface water, the water will pick up whatever is in that geology. This could range from fertilisers and pesticides used on agricultural land, to toxins released by both industrial and urban dumping. You also have to factor in the microbes and parasites that go unseen and live happily in the water supply.
So if we can’t get our water from a well, or a spring, due to the above issues, what are we left with? Well, there’s always tap water.
Tap water is chemically treated to reduce the incidence of bacterial and viral infectious agents being transmitted in public drinking water. However, due to an increased burden on the system by the reasons stated for spring water, plus the aging of the water system itself, South London, will know about this from last week’s draught, the quality of the water isn’t always as high as advertised.
The use of chlorine to treat water isn’t as foolproof as it’s professed. Chlorination is unable to eliminate all of the pathogens present in water. An even bigger issue is that by-products of Chlorine and Chlorine reactions in the water can cause Cancer. Not ideal, I might suggest. There are many more chemicals and reactions that make drinking public water, not the best idea for longevity, so what’s the alternative? Bottled water? Let’s look at that.
Bottled water is a huge business, with the largest manufacturers unsurprising owned by soft drinks companies…but, the question is ‘Is it any better?’. You be the judge.
A lot of bottled water is simply tap water passed through conditioning filters such as charcoal, to remove some of the chlorine and remove some of the taste and odours present in public water. You’ve probably got one of these filters at home yourself, most bottled water companies are simply charging you for the convenience of filling up your jug.
Bottled ‘spring’ water is a different case. If it states that it is spring water, it legally has to be from a spring. However, if it’s part of the brand name, it can be tap water, processed just as the other bottled water above is.
Here’s another problem with bottled water, and it goes a lot deeper, if you follow the rabbit hole. The majority of bottles used in the drinks industry are made of recyclable plastic; the chemicals that make this possible are also known as endocrine disruptors. That is, there are chemicals in the plastic used in the food industry (ready meals, cling film etc) that massively affect the hormonal state in your body. Noticed more moobs around lately? More Overweight people? Coincidence? If there’s interest, I’ll write a larger piece on this, but, you have to let me know.
So, we can’t drink from a natural spring, a well, or from the tap. Bottled water has its own set of additional issues. Water, water, everywhere, and not a drop to drink.
The best source of water is distilled water, which can be bought from a store, or more economically, after the initial outlay is to buy a home distiller and clean your own water. Get in touch if you want any advice on what to buy.
So, now we have clean water, why is it so important to drink it, and how much?
Dehydration is an undesirable state to be in. Although the article suggested that the dangers of dehydration are overstated, I feel the Doctor has failed to understand the biochemistry. If a cell in your body, be it from your muscles or your brain or any other part is dehydrated it undergoes a number of changes that induce a process known as apoptosis. Apoptosis is a programmed mechanism of cellular death. Again, I suggest, not a desirable state to be in. The body tries to limit dehydration, by reducing your ability to perform work or function, to conserve water supplies. If you dehydrate a muscle by only 3%, it’s ability to display strength decreases by 10% and speed by 8%.
The doctor also highlighted the fallacy of the ‘eight glasses a day’ recommendation. On this note the Doctor was spot-on, there has never been an official study that recommended this amount, it was one of those things that were repeated so often it become entrenched in our psyche.
So how much water do we need to be drinking, to stay hydrated and optimise function and performance?
A typical 75kg person contains about 5 litres of water, which needs to be replaced once every 5-7 days. This works out to just under a litre per day or 66ml per kg per day. If the person is lightly exercising, they will lose about 2 litres of water, in breath, sweat and urine; this also needs to be replaced. Heavy exercise may lose up to 7 litres. Even if you do not exercise, you will still have losses of around 0.5-1 litre per day.
So for our 75kg example, on a non-exercise day they would need to consume about 1.5 litres to stay hydrated. And if lightly exercising, probably 2.5 litres.
Also remember that your food and other beverages will contribute to the pool of water, both during digestion and metabolism, so this may reduce your water needs. And please do not rely on thirst as a measure of hydration, by the time your thirst response has kicked in, you are already dehydrated.
I also have an old article I wrote about a decade ago on using water to lose fat, if there’s interest, I’ll dig it out and post it.
No comments:
Post a Comment