Share Save Add as preferred on Google Chris Baraniuk Technology Reporter Getty Images The 2026 World Cup is the first to have mandatory hydration breaks in every game Booing fans and disgruntled pundits. One of the biggest controversies of the 2026 World Cup so far has been the hydration breaks, which – while not entirely new – are for the first time occurring twice during every match in the tournament.
The breaks aren't really about hydration , some spectators say. They're just an opportunity for certain broadcasters to show more ads, they break up the natural flow of games, and are unnecessary in air conditioned stadiums.
Whether or not you agree with these complaints, there's no doubt that hydration itself is an increasingly prominent point of discussion worldwide.
"Hydration is a key issue," says Andreas Flouris at the University of Thessaly in Greece. "We definitely see it, from a scientific point of view, gaining more and more attention."
Climate change is intensifying heatwaves , and in response public health campaigns are encouraging people to drink more fluids.
It is in this context that hydration-focused gadgets have flooded the consumer electronics market in recent years. They range from sweat monitors to toilet bowl urine-analysers. But do they work?
Not drinking sufficient water is a common problem. A 2023 study suggested that one in four UK adults aged 65 or older were dehydrated, due to not drinking sufficient fluids.
And a 2018 study by Flouris and colleagues assessed hydration levels in 139 workers around Europe. They found that 70% were dehydrated to a level that could negatively affect their thinking and control of their movements.
Purveyors of hydration tech say their products can help. Years ago, gadgets such as the Apple Watch and Fitbit made step-counting popular, says Roozbeh Ghaffari, co-founder and chief executive of US-based Epicore Biosystems. But why stop there? "Sweat has been the next chapter," he asserts.
His company is one of several that makes sweat-analysing devices. In Epicore Biosystems' case, that includes single-use sticky patches and sleeve-like wearables, which track the flow rate of sweat as it emerges from your skin, the sweat's sodium (salt) content, and skin temperature, among other metrics.
A new armband and app combo also offer to evaluate your "hydration readiness" based on "real-time sweat data". The idea is to avoid dehydration creeping up on you.
"With this new generation of our wearables, we could figure out what type of risk profile you have based on your sweat score," says Ghaffari.
Some of Epicore Biosystems' devices vibrate gently when they calculate that it is time for you to take a swig of fluid, to avoid becoming dehydrated.
The company says its devices are used by athletes but also workers on building sites, at oil and gas facilities, and on the ground at airports, where exposure to high temperatures and physical exertion are common features of the job.
Flouris is a little sceptical of sweat-sensing.
Referring to various unnamed devices that analyse sweat, which he has evaluated in the lab, he says, "Most of these products that we've tested do not show the level of accuracy that you would expect." The results of his experiments are as-yet unpublished.
Sweat sensors, Flouris suggests, work best when worn during long bouts of physical activity – such as a marathon. But they struggle when the exertion is more varied and intermitte…