A study, published in PLOS, shows that wearable devices can detect illness at an early stage by tracking specific vital signs.

For two years, Michael Snyder, a scientist at Stanford University, wore seven different wearables including MOVES, Basis, iHealthFinger, Masimo Pulse Ox, RadTarge, Scanadu Scout and a Withings scale. These devices provided real-time measurements of physical activity, heart rate, skin temperature, sleep, blood oxygen, exposure to radiation and weight.

In one particular event, Synder saw the potential of wearables when he noticed his heart rate was elevated and his blood oxygen count was low. Recalling a past trip to Massachusetts, Synder believed he had been bitten by a tick and might have contracted Lyme disease. After his self-diagnosis and self-treatment, Synder's heart rate and skin temperature had entered normal ranges. Synder then received a blood test that confirmed he had contracted Lyme disease.

By alerting Synder to the changes in his body, the wearables were able to predict the incoming illness. As a way to further test the abilities of wearables, Synder conducted a study with 43 adults who were given the Basis watch for 11 months. Over the course of the study, researchers compiled more than 250,000 daily measurements.

Results showed the wearables able to show a correlation between reduced blood pressure and fatigue. They also distinguished between insulin-sensitive and insulin-resistant participants.

“Overall, these results indicate that portable biosensors provide useful information for monitoring personal activities and physiology and are likely to play an important role in managing health and enabling affordable health care access to groups traditionally limited by socioeconomic class or remote geography,” wrote Synder.

In response to these findings, researchers were able to develop an algorithm that warns wearable users of an incoming illness by the analysis of body measurements.