Water. Aqua. H20. Adam's Ale. It's pretty good stuff. We're mostly made of it, we have to drink lots to survive, and for years it has flowed safely from our taps in all its refreshing goodness.
But, in recent years, a number of drinks have emerged claiming to provide natural alternatives to plain old water. In 2016, the UK market for coconut water alone was worth over £100m, up 20 times from 2012. Others, from maple and bamboo to cactus and aloe water, are firmly on the health trend radar. But are they just a clean living fad or a tasty, healthy alternative to soft drinks?
One of the latest additions is birch water. Proponents cite its array of nutrients (manganese, potassium, Vitamin C, calcium and more). For others it's expensive and there's a lack of scientific research behind it.
TAPPED birch water launched in 2015 after its founders noticed people beginning to shun sugary drinks for low-sugar, low-calorie alternatives. "We've seen this over the last few years with coconut water," says founder Paul Lederer, "and now with the next wave of 'alternative waters', such as aloe water, cactus water and 'straight from the tree' waters such as birch water and maple water. People are increasingly turning to alternative waters and hydrating drinks that are more natural."
Birch water has a long history, having been an important folk drink for centuries. "People in the Nordics and Baltics have, every spring, often following a harsh winter, enjoyed birch water as a rejuvenating and uplifting tonic," Lederer explains.
While it may provide a much-needed pick-me-up after a harsh Nordic winter, is birch water - and other waters for that matter - worth the hype?
Nutritionist Lily Soutter is unconvinced. "A lot of these water alternatives are really expensive, and I don't think they're necessarily worth the cost," she explains. "They're being dubbed as trendy new health drinks. They do come with things like amino acids, some antioxidants and vitamins, but you can get those elsewhere for a fraction of the cost."
For Soutter, there's nothing wrong with drinking alternative waters, but it's important to be wary, and it depends on how you're drinking them. As a replacement for sugary soft drinks, there's no problem - most are lower in sugar and more nutritious. "They're not necessarily harmful products, people shouldn't be avoiding them or scared of them. What I want to get across is that people shouldn't be fooled by claims."
The claims Soutter refers to are most evident around coconut water. "I've had clients who have downed a litre of coconut water, not realising there's 6 grams of sugar per 100ml, so they're ending up having 60 grams in one sitting. With fruit juice we're not being fooled, but with coconut water the message isn't so clear."
According to TAPPED, its pure birch water contains a quarter of the calories of a typical coconut water and very little sugar. Its flavoured birch waters, such as bilberry and lingonberry, and elderflower, contain 8-9g of sugar per 250ml; Coca-Cola has 10.6g per 100ml.
And Lederer doesn't want birch water to replace water. "We'd never suggest or expect that people would stop drinking ordinary water and drink birch water instead." But if it could help people cut down their sugar intake by switching from soft drinks, that could only be a good thing.
"The main takeaway is that it's better to quench our thirst with tap water," says Soutter. "If you want to indulge in these waters, there's nothing wrong with it, but be wary."
Five other alternative waters
Coconut water is heralded as a refreshing, thirst-quenching drink. It's the clear liquid obtained from immature, green coconuts. Nutritionally, it's unlike coconut milk, cream and oil, which are made from the flesh.
The water has many proven benefits: potassium, magnesium, and especially electrolytes, so if you're doing lots of sport, it can help replace them.
The problem, as Lily Soutter shows, is in the marketing, with many unaware of the relatively high sugar content. Coconut water's sugar is free sugar, which is the type found in cane sugar, honey and agave. It's the stuff we need to cut down on - government targets are set at around 25g per day. If you downed a carton of coconut water, you could have up to 60g.
Maple water comes straight from the maple tree, but is thinner and less sugary than maple syrup. It's tapped in a short window before it can be boiled down to syrup.
There are supposedly up to 50 nutrients, and bone strengthening and anti-inflammatory advantages. According to Soutter, maple water has a lot of manganese, which is crucial for nutrient absorption, bone development and the production of digestive enzymes. "But people don't tend to be deficient in that mineral", claims the nutritionist.
It's more commonly found in whole grains, nuts, leafy vegetables and teas, a lot cheaper than maple water which retails at around £2.49 for 250ml.
Bamboo water has hydrating properties, is sugar free, and is calorifically almost negligible. It supposedly prevents ageing by boosting collagen production, and contains silica, promoting healthy skin, hair and nails.
It's incredibly sustainable, as bamboo is one of the fastest growing plants, and has been consumed by the Chinese for years. But again, the science behind it is still in its infancy.
A 250ml bottle will set you back £2.
Made from the prickly pear cactus, this water has antioxidants, vitamins and minerals, can give your immune system a boost and has anti-inflammatory properties. But again, the science is inconclusive, and it's expensive at 25p per 100ml.
"There is research out there in terms of aloe vera helping with digestion and blood sugar levels," says Soutter. "While it can be helpful for some people, it is also a natural laxative and can cause stomach cramps and allergic reactions."