Track your eating habits with tooth-mounted sensors

Remembering everything you have consumed can be difficult, and most people are guilty of mindlessly eating. This makes it difficult to understand the impact of food and drinks on health, but what if there was a way to accurately track what you consume? Scientists may have found a solution using a tiny device inside the mouth.

Researchers from the Tufts University School of Engineering have created miniature sensors, as small as 2 x 2 mm, that can be mounted directly onto a tooth to monitor dietary intake in real time. The sensors wirelessly send information about a person’s consumption of glucose, salt and alcohol to a mobile device, similar to electronic toll collection.

Fiorenzo Omenetto, PhD, corresponding author and the Frank C. Doble Professor of Engineering at Tufts, explained, “We have extended common RFID [radiofrequency ID] technology to a sensor package that can dynamically read and transmit information on its environment, whether it is affixed to a tooth, to skin or any other surface.”

Made up of three sandwiched layers, the sensor has a central “bioresponsive” layer that absorbs the nutrient or chemicals, surrounded by two outer layers consisting of two square-shaped gold rings. They act like a tiny antenna, collecting radio waves and transmitting them back in an altered form, depending on what it detects. For example, if the bioresponsive layer takes on salt, this will cause its electrical properties to shift, which will result in the sensor absorbing and transmitting a different spectrum of radiofrequency waves.

“In theory we can modify the bioresponsive layer in these sensors to target other chemicals — we are really limited only by our creativity,” Omenetto said.

Other wearable devices have been developed to monitor dietary intake, but they have a number of downfalls including bulky wiring, requiring the use of a mouthguard and needing to be replaced frequently. However, this sensor can flexibly bond to the irregular surface of a tooth, as well as many other surfaces, and has the potential to detect other nutrients, chemicals and physiological states.

So sneaking some chips or a beer into your diet might not be as easy in the future.

The research was published in the journal Advanced Materials.

Image credit: Tufts University.