Teenagers are well-known to turn a deaf ear when told to something by a parent, teacher, sibling or just people in general, however, they are quite happy to make an exception for a machine.

British researchers have shown, obese adolescents can be made to lose weight, including being trained to make better mental connections between meal size and feeling full, with the help of a computerised device that tracks how much and how quickly the user is eating.

The Swedish developed Mandometer consists of a scale that sits under the dinner plate and weighs food on the plate. It is also connected to a graphic screen representing the ideal eating speed and any deviation from that line i. e. eating far too slowly or much too quickly, prompts a voice instruction.

The user at regular intervals is asked to rate his feeling of fullness, which appearing as a dot on the screen forms a graph with the progression of the meal, which is also then compared to an ideal pattern for normal weight people.

In a trial of the Mandometer involving 54-teenagers, researchers from the University of Bristol compared their progress with that of 52 similarly obese young people receiving only dietary advice, over a year.

The Mandometer group not only reduced their preferred food portion sizes over the study period, they also lost weight, maintaining improvements over the next six months, when they did not use the machine.

Study lead Anna Ford writing in the medical journal BMJ said the therapy ‘seems to be a useful addition to the rather sparse options for treating adolescent obesity effectively without drugs.’

The talking, computerised weighing device not only helped obese children eat smaller portions, it also ensured they reduced their speed of eating by 11%, resulting in significant weight loss.

According to experts, eating fast interferes with an inbuilt signalling system responsible for the brain indicating the stomach is full and it is time to stop eating.