Validity of the Bite Counter device in a controlled laboratory setting

Body-borne sensors may be useful in assessing eating behaviors and have the potential to overcome some of the limitations of self-report instruments. The Bite Counter is a new commercial device, worn on the wrist that purports to track the number of bites taken per day. It contains a tri-axial accelerometer that detects an upward, arcing motion from the table to the mouth, known as a wrist roll.

To examine the validity of the Bite Counter device for measuring bites in individuals while consuming various foods and beverages.

15 adults (23-58 years old) wore the device on the wrist of their dominant hand. They were presented with a meal consisting of foods/beverages, each consumed with different utensils: meat (knife and fork), side items (fork), soup (spoon), pizza (hands), can of soda (hands), and a smoothie (straw). Each food or drink was consumed by itself, in consecutive order. A researcher observed them through a one-way mirror and counted the number of bites taken.

The percentage of actual bites taken varied as follows: Meat (127%), side items (82.6%), soup (60.2%), pizza (87.3%), soda (81.7%), and smoothie (57.7%). The overall mean was 81.2% of bites taken.

The results indicate that the Bite Counter holds promise for being able to count the number of hand-to-mouth movements. In general, it underestimated hand-to-mouth movements, but some types of hand movements caused overestimation of bites. Future studies should be undertaken to improve the sensitivity and specificity of the Bite Counter device.