A review of devices using modern dietary assessment methods for reducing obesity

A sensor is a device that senses, perceives, or distinguishes and responds to an input from a physical location and provides an output that is human decipherable. As obesity levels all over the world are reaching the sky, especially in the U.S., China, and India, the use of sensors can help in managing rising obesity levels. There are many traditional dietary assessment methods such as doubly labeled water, 24-hour recall, paper-based food diaries, and food frequency questionnaires used for managing and reducing obesity, but they have many limitations. Therefore, modern dietary assessment methods such as acoustic-, image-, motion-based, unobtrusive, and multimodal methods have been developed. Devices that use these modern dietary assessment methods are automated wrist motion tracking system, WearSens necklace, and automatic ingestion monitoring system. This study provides a review of such devices that help in reducing obesity for better living in humans.