Imagine not only tracking calories burned, using an activity tracker, but also calories eaten. It would make staying healthy and maintaining a stable weight much easier. And it's nearly here.

Scientists at GE Labs in New York are currently perfecting a technique that uses microwaves to scan any food and instantly deliver its calorie count. This universal calorie counter could find it's way into an activity tracker, or working with one, once it's perfected.

The tracker breaks down food into three groups: water content, fat content and weight. Using an equation it can then determine calories within 5 per cent accuracy.

At the moment it's only being used on liquids but a unit for solids, like the prototype pictured above, is being developed. The next stage could be activity trackers that work with these units. If there's a way around weighing the items perhaps the scanner could even be built-into the tracker or a phone, which already uses microwaves anyway.

It's still early stage stuff but very exciting indeed for the future of health tracking.

at last activity trackers that measure calories in any food are almost here image 2

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