Sensor on a tooth that can record what you eat and drink

A TINY sensor that can be fitted to a tooth to monitor your alcohol, sugar and salt intake has been devised by scientists.

The 2mm x 2mm device, pictured, connects wirelessly to a user’s mobile phone and records information on what they are eating and drinking.

It could help doctors advise patients on their diet and check that they are sticking to it.

The sensor, developed at Tufts University School of Engineering in the US, could be another step forward in health monitoring where activity trackers such as Fitbits have already had an impact.

The researchers, who have published their findings in the journal Advanced Materials, say their device could be adapted to detect a wide range of nutrients and chemicals, and even monitor stress hormones in saliva. Such sensors could also monitor sugar or salt intake for people who need to limit it, and check dental health. One application could be for patients with high blood pressure who have lost their sense of taste. Too much salt in the diet can cause blood pressure to rise, and the sensor could warn when too much salty food has been eaten. Another use could be monitoring glucose intake for people with diabetes.

Up to now, monitoring what people eat has been difficult because of the bulk of devices designed to go in the mouth. This sensor is composed of three sandwiched layers: a central layer that responds to the nutrient or other chemicals to be detected, and two outer layers consisting of two square-shaped gold rings.

When the inner layer is activated, it works with the outer layers to act like a tiny antenna, collecting and transmitting waves in the radio-frequency spectrum.

Dr Fiorenzo Omenetto, who devised the sensor, said: ‘In theory we can modify the bioresponsive layer in these sensors to target other chemicals.’

He said they had created ‘a sensor package that can dynamically read and transmit information on its environment, whether it is affixed to a tooth, skin or any surface’.