It seems like every week a personal health sensor is designed that can track something we never thought to track, but are they actually effective?

Personal health sensors are more popular than ever. Many have proven to be helpful while others are met with similar skepticism to other electronic devices available to the public. Any device entering the realm of technology for consumers is going to be talked up by its designers, but the science behind some of these devices can be new and hasn't had much testing.

These devices are always intriguing because the ones that work have the potential to make medical diagnostics less-invasive, but the potential doesn't always pan out. This potential is what makes personal health sensors such a point of interest in electronics, but it helps to research which technologies actually better people's lives, and which technologies are made simply to sell units. We came across 2 interesting devices that seem promising, but we'd like to learn more about them. 

Breath tracking for fat loss

A new device that tracks fat loss was by measuring breath unveiled at CSE in Las Vegas back in January. LEVL measures the acetone in somebody's breath in order to calculate the effectiveness of their fat burning state. Acetone is a ketone, that is said to be indicative of fat loss, but until now has been too small trace with sensors available to consumers. The device works similar to a breathalyzer test; you exhale into a "breath pod" and an unspecified "groundbreaking nanosensor that brings an elegant, powerful technological solution to the world of weight loss" tracks the concentration of acetone in your breath. The Science section on LEVL's website only has research from one doctor. Unfortunately, there are also a lot of infomercials for various miracle cures that involve a single doctor's research. The idea sounds promising, but we'd like to see more information about acetone's correlation to weight loss and how the nanosensors themselves work. You can see Dr. Joe Anderson explain how LEVL works in the video below.


Emotion tracking in a wristband

Feel, a wristband that detects emotional state using sensors, the most notable of which is a sensor for Galvanic Skin Response (GSR) also known as electrodermal activity, that detects Electrodermal Response (EDR). The 3 other sensors are a blood volume pulse sensor, a skin temperature sensor, and an IMU to help "measure movement and activity in order to improve Feel’s emotional recognition and prediction." The sensors measure indicators that have grounds in science, such as heart rate, sweat, and breath rate, but their connections to somebody's emotional state are correlations at best. This leads to some controversy as to the validity of measuring human emotions.  

A lot of people are skeptical of electronic sensors for things like human emotion, dismissing them as pseudoscience, or even more harshly as snake oil. Feel's website has a science page, but the preview for Feel, which consists of a minute and 23 seconds of the Feel twirling in a circle doesn't inspire confidence. 

Feel's features


We'll stay optimistic about these new devices until more research comes out. After all, a lack of research doesn't always mean that a hypothesis is false. The makers of both these devices might want to have their research teams and PR teams have a meet-up, however. If anyone reading this works on health-based wearables or sensors, we'd love to know what you think about acetone measurement or Galvanic Skin Response in the comments.