Wearable health-monitoring devices are nothing new, but consumer-grade models are usually limited in function and have a cool factor usually associated with mall walkers.

Now, there's some new hope on the horizon: a tattoo ink that's able to provide its owner with real-time health assessments.

According to Nerdist and first reported by the Harvard Gazette, researchers at Harvard and MIT have broken ground—or technically, skin—on a procedure that uses a special kind of ink to evaluate certain health markers. This "smart" tattoo ink can assess an individual’s blood sugar level, a benefit to diabetics; another biosensor tattoo can measure dehydration levels. If the ink detects a shift, it changes colors. (Nerdist calls it a "mood ring" for your health.)

The project, dubbed "DermalAbyss," was mounted when postdoctoral fellows at both universities wanted to address drawbacks in current wearable health tech. Battery life is one factor; wireless connectivity is another. But "smart" ink doesn't need either. The ink responds to changes in the wearer's interstitial fluid, which can provide information on glucose levels and sodium concentration.

The researchers note that they'll need to continue to experiment with the ink (currently being tested on pig skin) to make sure it doesn't diffuse or fade. For people who might want the benefits of such monitoring without having a portrait on their arm, the team also suggests an "invisible" ink that can be seen only when observed under the light of a smartphone. 

[h/t Nerdist]