get fuel from your body

"Fuel cell technology is hyped as a possible future power system for electric vehicles, but it's actually got a plethora of uses: The latest, and perhaps greatest, is a glucose cell for medical devices that could get its "fuel" from your body.  The innovation is coming from France's Joseph Fourier University, where they've been experimenting with the complex physics and chemistry needed to create a miniature glucose-powered electricity generating device. The goal was to make the device practical in terms of acquiring its fuel directly from a living body--where it also serves as a fuel, of course--and also in terms of generating enough electricity to power embedded medical devices like pacemakers."  http://www.fastcompany.com/1649666/fuel-cell-glucose-human-food-medical-technology-medicine-power