It’s a whole new way to ‘double your pleasure:’ After you’re done chewing your gum, spit it out and turn it into a sensor.

That’s what researchers at the University of Manitoba and the Manitoba Children’s Hospital Research Institute did—and they found that a stick of Doublemint gum doubled up well as a stretchier, highly sensitive biosensor.

The gum just needs a little chew (about 30 minutes will do), then an ethanol cleaning before carbon nanotubes are stretched and folded into the gum, turning it into an active sensor.

All the gummy strength that goes into blowing a bubble is also perfect for medical body sensors: When a patient moves, the gum can stretch and bend, even under high strains. The new smartgum is also sensitive to humidity and could be used to track breathing.

Pricing out at under 3 bucks a piece, the gum sensors are much cheaper than other alternatives engineering professor Malcolm Xing says he’s tried.

It’s the latest thrifty find in a rapidly-evolving $10 billion-plus biotech market that’s shifting away from bulky machines towards stretchy tattoo-like monitors, fingertip-sized electrical boards, injectable dyes, and ingestibles.

And for Xing, all it required was a trip to the local supermarket.

Check out the tiny motion sensors inside Kinect video games:

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