Named WearSens, the close-fitting metal necklace determines the type of food a person eats by measuring the vibrations generated during swallowing and digesting of the food.
As a substance travels down the throat, it creates tremors that can be tracked on the skin around the neck. With its piezoelectric sensors, the necklace is sensitive to mechanical changes and records the vibration, Popular Science reports.
Each type of food produces a distinct vibration, so the device is able to discern between the vibrations resulting from a person eating something soft like mashed potatoes and something crunchy like a packet of chips.
As the device determined what type of food a person ingests, and how much food is consumed, the information is then sent to user’s smartphone app.
As vibrations vary in intensity from person to person, each individual device needs to be calibrated for the specific characteristics of the person wearing it.
“To personalise the device, we ask a new wearer to eat a 3-inch (7.6-centimetre) Subway sandwich and then sip down a 12-ounce (350-millilitre) drink,” UCLA electrical engineer and co-developer Majid Sarrafzadeh told Popular Science.
The findings were published in IEEE Sensors Journal.
The study indicates the device can distinguish between solid and liquid food 90 percent of the time, while in 75 percent of cases the device successfully distinguished between hard and soft foods.
The device is described as an “innovative wearable nutrition monitoring system”, saying that it will offer “unprecedented visibility into individual nutritional wellness”, according to the information on its website.
Additional research on WearSens could determine whether a person is smoking cigarettes or consuming pills, with opens new directions beyond monitoring nutrition.