Sixty is a startup with a simple mission, to help you drink more water. Because, chances are, you're probably not.
You might think you already drink plenty - in fact, seven out of 10 of us think we do, according to Sixty's CEO and founder Paul McAleese. "The reality is that nine out of 10 people don't drink enough water," he told us.
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Sixty has been working on hydration tracking for some time, with the current goal of bringing a simple, wearable tracker to market in around a year's time. If its name seems a bit opaque, it's explained by the fact that humans are made up of 60% water.
It sees widespread dehydration or under-hydration as a behavioural issue, with people simply not trained to keep themselves hydrated. "Water helps you in terms of your performance, your physical as well as cognitive performance," he said. "It improves your skin health and your metabolism. It helps you recover faster, avoid injury."
Hydration tracking from the wrist
Sixty's current mock-up of its initial device currently looks like a really simple monitor in terms of display and information, with a straightforward tower of LEDs as indicators of your hydration levels.
That design is very much open to change, though. Although the monitoring technology on the back of the central unit is at an advanced stage, Sixty hasn't finalised yet what the actual "face" will look like. It could end up with a watch face, and more smartwatch features, or remain simple and minimalist, depending on the feedback the company receives during the months of testing to come.
Water helps you in terms of your performance, your physical as well as cognitive performance. It improves your skin health and your metabolism. It helps you recover faster, avoid injury.
Sixty's idea of how its wearable monitor is used is also adaptable. For users who want constant monitoring it can be worn on a wrist or arm strap, while those who only want to check their levels every so often can simply carry the free-standing monitor with them without a strap and use it as desired.
This could see it being useful for athletes or fitness lovers who want background measurement at all times, as well as for less dedicated users who simply want to be able to check up when needed.
How Sixty's hydration monitor works
As McAleese explains, with a similar method to an optical heart rate monitor, Sixty's monitor, "essentially shines a light of a certain wavelength onto your skin, and measures hydration at different depths through your skin, so that you can get a correlation to an overall body hydration as opposed to just a superficial skin hydration." This is then translated to a simple metric for you to know if you should take a drink before you start to actually feel thirsty.
"It is 10 times more accurate than your thirst reflex. It can detect when you've lost 30-40ml of fluid, and as a result prompt the user to drink well in advance of them feeling thirsty or detecting any ill effects from dehydration." Your natural inclination to feel thirsty typically kicks in after 300-400ml of fluid is lost.
Making sure that this indication is completely accurate is one of the major challenges facing Sixty in the year to come. It will be embarking on extensive data-gathering to make sure that it has data on as many phenotypes as possible to demonstrate its accuracy. What's a phenotype? Well, you are; so are we - a phenotype is effectively just a variety of human, depending on characteristics such as body weight, height, activity levels and more.
The price of tracking your hydration
At the moment the idea is to retail Sixty's wearable at between ¬£120 and ¬£180. If it ends up with a full display and smartwatch features that number will end up in the upper regions of the scale, while more pared-back versions could be lower. With a series A funding round about to start, an injection of money could also result in change on the cost and features front.
Sixty has also recently announced a collaboration with Britvic as part of its hydration tracking journey. "The partnership with Britvic is purely around promoting the importance of hydration. Going forward it may evolve into something more significant in terms of development but that's all to be determined," McAleese told us.
The startup is also exploring the possibility of partnering with mainstream manufacturers to see the technology it's working on integrated into other wearables and smartwatches. That raises the real possibility that hydration monitoring could become part of a new wave of features for smartwatches in the coming years, just as heart rate monitors have now become staple features on our fitness trackers and smartwatches.