Imagine it’s the year 2040, and a 12-year-old kid with diabetes pops a piece of chewing gum into his mouth. A temporary tattoo on his forearm registers the uptick in sugar in his blood stream and sends that information to his phone. Data from this health-monitoring tattoo is also uploaded to the cloud so his mom can keep tabs on him. She has her own temporary tattoos—one for measuring the lactic acid in her sweat as she exercises and another for continuously tracking her blood pressure and heart rate.

Right now, such tattoos don’t exist, but the key technology is being worked on in labs around the world, including my lab at the University of Massachusetts Amherst. The upside is considerable: Electronic tattoos could help people track complex medical conditions, including cardiovascular, metabolic, immune system, and neurodegenerative diseases. Almost half of U.S. adults may be in the early stages of one or more of these disorders right now, although they don’t yet know it.