Apple is quietly developing sensors that can track the body’s blood sugar levels in a bid to help people with diabetes, CNBC reports. The company has apparently hired a small team of biomechanical engineers to work on the project, which would monitor glucose levels through contact with the skin, rather than through invasive blood tests or similar mechanisms.

It’s apparently been working on the sensors for five years

The company is basing the team working on the sensors out of an office in Palo Alto, rather than at its main headquarters. The engineers have apparently been working on the sensor technology for at least five years, and it is complete enough that Apple has started feasibility trials at clinical locations in the Bay Area. The company has also hired consultants that are helping it navigate complex health regulations, CNBC says.

The team is reportedly managed by Johny Srouji, Apple's senior vice president of hardware technologies, but previously reported to Michael D. Hillman before he left the company in 2015. CNBC says the team is made up of about 30 people, including biomedical experts Apple hired away from major firms like Masimo Corp, Sano, Medtronic, and C8 Medisensors. Those hires, reported early last year, sparked speculation that Apple may indeed be working on such a product.

The idea of wearable devices being used to manage conditions like diabetes was developed during Steve Jobs’ tenure as Apple head, but developing technology that can accurately measure blood sugar levels without piercing the skin is particularly difficult. John L. Smith, a biomedical expert who has published papers on the failure of non-invasive glucose sensors, said it was "the most difficult technical challenge I have encountered in my career."

Google is also developing glucose monitors

Apple’s in-development solution reportedly shines light through the skin to check current glucose levels. Google is also working on its own glucose monitors, but has taken a different approach. The company is currently developing a contact lens that is intended to track blood sugar through contact with the eye, and a bandage-sized device being developed by its Life Sciences division.

It’s not yet clear when Apple’s sensor will be complete, nor whether it would come as part of its own device, or be included in an Apple Watch or similar product down the line. If it can pull it off, however, the sensor could make life easier — and Apple products more desirable — for people with diabetes.