Researchers from Britain have revealed that a computerized gadget that manages to keep track of how much, and how quickly, the user is consuming food can help youngsters drop extra weight by training them to make better "mental connections" between how much they eat and how full they feel.

The device, developed in Sweden, has been christened the Mandometer, and manages to connect a scale that sits under a dinner plate to a graphic screen that represents the required and good speed of eating. The scale weighs the food on the plate. When a user begins to eat too fast or too slow, a voice prompt ensures that the eating speed is sufficient.

At regular intervals, the users are required to rate their feeling of how full they are, which then appears as a dot on the graphic screen, forming a graph as the meal goes on.

The rail of the device was conducted on 54 teenagers and their progress was tracked for a year with 52 obese youngsters who only received dietary advice. The Mandometer group participants managed to reduce, not only their weight, but also their preferred meal portion sizes.

“The therapy seems to be a useful addition to the rather sparse options for treating adolescent obesity effectively without [drugs]", wrote study leader Anna Ford.