Forget Fitbits and sleep trackers; a new sensor worn on teeth records much of what a person eats or drinks in a day.
The sensor, which is mounted directly on to a tooth and connects wirelessly to a user's mobile phone, records information on their sugar, salt and alcohol intakes, a study by Tufts University found.
The researchers believe the device could help people manage their nutritional inputs, leading to improved health and diet outcomes, according to The Daily Mail.
Read more: • Why an 'eating window' is key to losing weight
Such sensors could also be used to monitor dental health, as well as potentially collecting saliva samples to measure wellbeing complications, such as fatigue, they add.
Measuring just 2x2mm, the device overcomes previous limitations of such technologies, including requiring users wear a mouth guard, and adheres well to uneven teeth surfaces, according to the researchers.
It is unclear when such a device may be available for public use.
How could the sensor be used?
Speaking of the implications of the device, study author Dr Fiorenzo Omenetto from Tuft University, told Alphr: "Managing and interpreting the data that this device provides can ultimately lead to the identification of patterns of consumption that could have an impact on diet regimens, health management, and maybe make us more aware our nutritional intake.
"One could envision nutrition monitoring and relate that to nutrition management.
"On the other hand, sampling and monitoring analytes in the oral cavity could help in a number of ways: from monitoring dental health to monitoring fatigue through saliva sampling."
"We are limited only by our creativity"
The researchers add the sensor does not include bulky wires or require changing regularly.
Reports suggest the sensor only lasts up to two days, however, further development could extend this.
The device can also be attached to other body parts and be tweaked to pick up on many different chemicals.
Dr Omenetto added: "In theory we can modify the bioresponsive layer in these sensors to target other chemicals - we are really limited only by our creativity.
"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."
The findings will be published in the journal Advanced Materials.
How does the sensor work?
Made up of three sandwiched layers, the sensor's central 'bioresponsive' band absorbs nutrients and chemicals from food, which causes its electrical properties to change.
The outer layers, which include two square-shaped gold rings, act as tiny antennae.
These absorb and transmit a specific spectrum and intensity of a radiofrequency wave.
This wave then gets wirelessly transmitted back to person's mobile phone.
Users can also instantly see when their intake of a certain substance is high due to the sensor changing in response to chemicals found in salt or alcohol.