01.Introduction
A quick look at supermarket and health store shelves, not to mention the temples of snake oil proliferating on the internet, will have you believe plain old water just isn’t good enough anymore: if it doesn’t have one or more magical properties, such as a particular pH, extra oxygen, magnetic properties, or a specific polyhedronic structure, it’s not good enough to quench your thirst.
Here, we take a look at the marketplace and the science - or pseudoscience - behind some of the claims.
Alkaline water
Also called ionised water, alkaline water is promoted for detoxing, and claims to increase vitality, slow ageing processes and prevent diseases including cancer and diabetes, all by virtue of having a higher pH (about 9) than tap water (typically around pH 7).
Alkaline foods and drinks are neutralised by stomach acid, so drinking alkaline water has no effect on the acid–alkaline balance of the body, which remains between 7.35 and 7.45. If the blood pH goes above this range (that is, more alkaline) the lungs help regain control by retaining carbon dioxide (you breathe more slowly) and thereby increasing the carbonic acid levels of the blood, while the kidneys increase excretion of bicarbonate in urine, making it more alkaline.
Drinking normal amounts of alkaline water won’t do you any harm, and many people consume high alkaline bicarbonate products for medical reasons (such as antacids to help alleviate stomach acid reflux and urinary alkalinisers for relief of urinary tract infection symptoms). But, equally, if you don’t have one of these conditions, there’s no evidence it will do you good.
Hexagonal water
The proponents of “structure-altered” waters argue that arranging hydrogen and oxygen atoms in a particular shape confers benefits in terms of increased cellular penetration and hydration ability. Hexagonal water is one such structure, with Penta water (pentagonal water) having largely gone down the gurgler when the UK Advertising Standards Association cracked down on its claims. These, and other forms of water “clusters”, are inherently unstable, have no observable properties, and offer no health benefits.
Vitamin water
In 2008, CHOICE awarded a Shonky to Coca-Cola Amatil for its range of Glacéau “nutrient-enhanced water beverages”. The Australia New Zealand Food Standards Code permits vitamins and minerals to be added to water-based beverages, but there are better ways of getting your vitamins and minerals – even a moderately healthy diet could provide the levels of nutrients included in these waters. On top of this, Glacéau VitaminWater contains enough sugar to provide an average woman with about one-quarter of her recommended daily intake. Measure for measure these beverages have less sugar than a typical soft drink or juice, but don’t kid yourself they’re anything other than a sweet treat.
Coconut water
Currently enjoying fad status,
coconut water has been marketed as a healthy alternative to sports drinks and other bottled beverages. While it does contain some useful nutrients, such as calcium, magnesium and phosphorous, they’re in amounts smaller than those found in fruits and vegetables, and there’s no evidence it lives up to other claims such as assisting in weight loss, improving skin tone and helping with digestion. It doesn’t offer any advantages over sports drinks or regular water for performance and
rehydration during or after exercise.
Oxygenated water
Spruikers of oxygenated water claim that the extra boost of oxygen can help athletes and other people who could benefit from the extra dose of this life-giving gas. However, the amount of oxygen we normally breathe in (about 3000mg per minute) vastly exceeds that contained in a bottle of water (150mg in the case of Oxygenizer brand).
Sports water
Mizone Formulated Sports Water looks like water but is flavoured and contains salt and sugar. It’s marketed for sports hydration, and while it meets the standard for electrolyte drinks (or "sports drink") in terms of sodium, it has less sugar than other sports drinks, so can’t technically be called a sports drink, hence the term "sports water" (see our article on Exercise rehydration for more on sports drinks).
Aroona Sports Body Quencher, on the other hand, is just plain water in a pop-top bottle with pictures of people doing sports on it.
Unique water
This water was released onto the market in 2002 accompanied by great hype and the usual ringing endorsements that accompany miracle products from current affairs TV shows and in other media. The water contains magnesium bicarbonate, which increases its alkalinity and provides a dietary source of magnesium. After coming under the scrutiny of the TGA for making claims about the therapeutic benefits of the water, the people behind it stumped up the money - reportedly millions - for a clinical trial, which was published in 2010, to test the claims of improvements in the acid–base balance of the body, bone metabolism, and cardiovascular risk factors. The trial results did indeed show an increased urinary pH, thanks to the bicarbonate, and increased blood magnesium levels. But while magnesium is an essential nutrient, the cheaper option is to simply take a pill if your diet is inadequate. The Unique Water website claims the product is “Too good to be true” - and indeed it is.
Balance water
Balance is a range of non-flavoured waters containing flower essences, with varieties designed to promote health and wellbeing through stress relief and relaxation. The company makes no attempt to substantiate its claims, rather it states: “Like many homeopathic remedies, most of the scientific evidence to date is anecdotal and based on case studies…” - which means there is no scientific evidence.
Myths that don’t hold water
Drink eight glasses a day
The old “eight glasses a day” equates to about two litres of water. Most people lose about one litre of water per day through sweat, urine and other bodily processes. Meanwhile, we’re eating a fair amount of water in food, as well as drinks such as tea, coffee, juice and so on. Once thought to be dehydrating, caffeinated drinks actually have little or no dehydrating effect (though alcohol does). How much you need to drink is an individual thing, based on your body size, the climate, and your diet and lifestyle. Drink to thirst.
If you’re feeling thirsty, you’re already dehydrated
The fear of dehydration, arguably beaten up by sports drink manufacturers and bottled water companies, has well and truly taken hold, and not only among elite athletes. Seemingly everyone, from dog walkers and train commuters to window shoppers can be seen regularly topping up from their water bottle wherever they go.
Dehydration may be a risk in extreme circumstances, such as doing heavy exercise in hot weather, but for most healthy adults going about their day to day activities, thirst kicks in before any detectable signs of dehydration.
Water helps with weight loss
While it may seem that drinking a glass of water should make you feel fuller – and perhaps eat less – this doesn’t appear to be the case. Like other drinks, water appears to dodge hunger receptors and has no effect on satiety. However, if you add water to your food, it reduces the energy density and may help you feel fuller, eat less and lose weight.
Studies have found that if rather than, say, a casserole accompanied by a glass of water, you eat the same ingredients as a soup, this is more filling and you’ll eat less at the next meal. So if you want to lose weight, consider making your dinner ingredients into a soup.
Drinking water will also help you lose weight if you drink it instead of juice and other sweet drinks, which contribute kilojoules but don’t reduce hunger.