It's almost a matter of pride, is not it? From the hard drinker to the tea swiller, from the coffee addict to the kola kid, 'water' is a dirty word.

Are humans really among those rare few mammals that need very little water to survive? After all, unlike desert creatures, we have no inbuilt water conservation mechanism. If you've read the early Dune sci-fi books, you'll have seen what might be done to get us that way – the 'still suit' – but it's hard real. No, we're not built at all for low water intake.

So, why do so many of us think that we can get by on a couple of pints of liquid a day, and even drink it with diuretics like alcohol and the caffeine in cola, tea and coffee? I do not reckon we think about it. We just think about convenience. Going to pee is an inconvenient time-waster, so avoiding much fluid intake seems sensible. But there's a heavy price for saving those few minutes each day.

If you're one of these low water intake people – and there are so many – you'll be amazed at how much more alert you get and how fast that 'sluggish' feeling goes when you begin to drink properly. The doctors do not go banging on about it for no reason!

Our Miracle Poison Eliminators

One of the fastest ways to attract serious bodily breakdown is to stop the elimination of poisons. Our bodies are constantly making waste. It's part of the state of being alive. Feces is the obvious one; so is breathing (it dumps carbon dioxide); and sweating is another, disposing of salts and some other chemicals.

Urine is a major waste disposer, too. It's the end product of a complex chain of processes, which start with waste disposal from every cell in our bodies. Just by living and doing their job, all of our cells absorb nutrients and oxygen and dispose of wastes like lactic acid directly through the cell wall. Our blood and lymph systems drain this away for processing in the liver, and our kidneys extract the waste delivered from the liver, store it in the bladder and pump it out periodically. Fine, so far.

Water is Vital for health

The thing is, all these processes depend on an adequate water supply to work. Dehydrated cells can not excrete poisons properly. One result is muscular cramp. Another is a poor ability to think straight, as your brain malfunctions. Why? Low water in our blood and lymph systems is very dangerous, and your body will yank this water from almost anywhere else in your body to keep up the blood functions without which you'll soon die – especially cleaning wastes from every cell in your body . And if, like most of us, you eat a high salt diet, your body needs even more available water to maintain the hydration balance between blood and cells. Or again, you die – painfully.

Concentrated urine is an early symptom of dehydration, and it can cause all kinds of malfunctions including kidney and gall stones. Birds have a mechanism to suck out almost all urine's water, giving the familiar white missile on your head! But we have no such ability. When our urinates concentrates too much, it's a sign of trouble.

A classic result of dehydration is those hallucinations (all those 'lost in the desert' stories) as your brain is reduced of water to keep the rest of you alive. Oh, and if you're dehydrated, you'll have digestive problems, too, principally constipation.

But we do not have to go too far down this road to be destabilized by dehydration. An early symptom is loss of concentration as the water is yanked from our brains to keep everything else going. That can be costy indeed. Migraine and headaches is another. So, if you want to avoid pain, or losing money by bad decisions or the risk of an accident, keep hydrating – drink!

How Much Water Should I Drink?

It's simple to do: follow the well-known doctor's advice to drink seven glasses of water a day. You'll find that you get more alert, feel fresher and maybe those headaches and migraines you get under stress will magically disappear. And, of course, you'll need to pee more often – but that's natural and healthy!

The water can be any drink with water in, that is not a diuretic (see above). So, soup, milk, fruit juice, herbal teas, and so on, all count. Water in your meals does not unless they are very water-rich, and do not forget to count calories in these drinks as part of your food. It is not my fault if you get fat! And drink steadily through the waking day – not liters at a time!

Maybe you want more specific guidance? Here are three easy tips to help you drink the right amount of water:

TIP ONE: Calculating daily water needs

Calculate your optimum water intake using one of these rough-and-ready rules – you'll only have to do it once.

• In pounds, drink half an ounce of water daily per pound of your body weight. So, if you weigh 150 pounds, drink 150/2 = 75 ounces of water a day. That's just under 5 pints US, rather less than 4 pints Imperial.
• In kilos, drink 3 / 100ths of your weight in water each day. So, if you weigh 70 kilos, drink 70 x 3/100 = 210/100 = 2.1 liters (same as kilos) of water each day – just over 2 liters.

That may look like a lot of water, but it's not! Most mammals voluntarily have a similar water intake. It's only humans who stubbornly resist drinking just for short-term convenience and despite getting those natural 'thirsty' signals. You'll see below how little it is each hour.

TIP TWO: Spotting Dehydration

First, look for a loss of concentration. If you've forgotten to drink in the last hour or two, then you've probably found the reason. But also keep a general watch over your urine concentration. Most people's urine is a deep yellow, and that's counted as normal. But most people are dehydrated! A simple motto is, PEE PALE. It's that easy. Apart from maybe the first time you go in the day, or if you're ill or eating something poisonous like whiskey and detoxifying rapidly, expect your urine to be a pale straw color. If it gets stronger, a definite deeper yellow, drink! It really is that simple. And yeah, you may have to peer into the bowl to check. Not really so gross, is it? I bet, if you're male, that you'll find yourself peering over into the next stall in public toilets – just to check what color … Betcha!

TIP THREE: The Daily Balance

Your body is naturally good at keeping a water balance – if it is not as poorly dehydrated as a lot of Westerners are. If you're a little dehydrated, your kidneys will allow less water containing a stronger concentration of wastes into your bladder – that's where the brighter yellow pee comes from.

Suppose you do not pee, even when you're getting the signals that your bladder's full and you need to (a gripping, 3-hour movie? Watching a long race?) Or suppose you're really dehydrated and short of water. Then your kidneys will stop processing waste – and the poison level in your blood begins to rise. A lot of people are at that high poison level all of the time, and concentration and bodily processes like efficient digestion and waste removal from your cells begin to deteriorate.

If, at the other extreme, you have a lot of water in your blood, then your bladder fills up quickly. You should pee more often, and your pee will be very pale.

Within limits, then, you can cope with quite a wide difference in water intake without problems. But if you over- or under-hydrate seriously, you'll get pathological conditions.

You'll function best if you have a regular intake of water – just the right amount each hour you're awake. So aim to drink your daily optimum of water evenly over the waking day. (When you sleep, the system pretty-well shuts down anyway. That's why a tall glass of water is a good first action when you wake up.)

Suppose you're a fella of 130 Kg, 150lb, and your optimum is around three liters a day. If you're awake 16 hours a day, that's roughly 200ml (about 7 ounces) each hour, and one hour you eat a meal which is mostly water – say, fruit or soup. If you're a svelte lady, and you need two liters a day, make it about 150ml an hour (about 5 ounces). Now, even if you're one of the dehydrated majority, that does not sound an impossible large amount to drink, does it?

If you find that you've become dehydrated, or you realize that you've forgotten to drink for several hours, drink an hour's worth right away, then another in 20 minutes to half an hour. That puts you back on track and your body will rebalance pretty quickly. What you must not do is try to make up all of the missed fluid. You've already adapted to its loss, and to drink this much at once will over hydrate you.

Be Sensible about Managing Your Water Balance

These are pretty rough-and-ready figures in Tips 1 and 3, so do not get too rigid about it. (You might have noticed that the pounds and kilos conversions are not quite the same, but they're simple to work out.) If you drink double the amount shown, you're over-working your kids – not a good thing. If you drink half, you're pretty dehydrated. Be sensible about it.

If you're drinking diuretics, you're forcing your kidneys to process more water than you should, so you'll pee too often. The result is that you have to drink more to stay hydrated. The most common diuretic drinks contain stimulants like caffeine and taurine, or alcohol, or maybe both! So anything strongly alcoholic, especially shorts, liqueurs and wine, will need water to balance it. So will tea, coffee, chocolate, colas and sports / energy drinks (Red Bull, for example) – and the stronger they are, the more water you'll need to balance them. They all contain poisons and will cause a detox effect anyway, so judging the right balance is not easy. Weakish tea or coffee, or most colas, will not need much water to balance out. Strong stuff like extra-strong tea, coffee shorts and taurine-kick sports drinks, might need more water than the drink itself to balance out. Italians do not drink water with their coffee shot for nothing!

One last point: if you're sweating freely, the rules are different. I'm thinking of extreme conditions, like being in a blood-temperature, humid environment or working hard in a very hot environment, or working super-hard anywhere. Examples are: long distance runners, cyclists and swimmers; underground coal miners; furnacemen; shot blasters in full remote air gear, sugar cane cutters. In these conditions, you can quickly excrete more water than your body can afford to lose. You may also lose too much salt, one of the few situations where you may get salt-deficient. The answer, just while the heavy sweating is happening, is to drink extra water to make back the sweat losses, with a pinch of salt added to each liter. No need for expensive specialist drinks – if you need sugar for blood-sugar top-ups, use honey or a low acid fruit juice (eg, melon) in the water. There's no stimulant poison in the home brew and you know what you're getting!

Overall, your attitude to hydration should be simple: be sensible. Tip 2 is your common sense guide – pee pale!

Happy drinking!