At one level, the programmes are a symbol of the superficiality of our times, the triumph of appearance over substance. They also convey the message that anything can be bought - looks, youth, elegance, happiness.

They hold up the prospect of an unappealing society of the future, in which everyone, not just celebrities, must have an image consultant.

At another level, however, the makeover programmes raise interesting issues, with significant educational implications. Even very young children now have a strong sense of fashion and are keen to be seen in the latest designer outfits - an attitude encouraged by many parents, who themselves may be victims of the consumer society. When youngsters reach adolescence, the pressures can become acute as they try to come to terms with physiological changes, emotional highs and lows, and peer-group influence.

All this is part of identity formation and the (sometimes painful) transition to adulthood. Clothing, hairstyle, piercings, tattoos, can serve a number of functions - as symbols of protest, as an expression of group solidarity, as an assertion of individuality.

Then there is the whole question of body image. We hear a great deal about the problem of obesity among the young, their poor diet and failure to take sufficient exercise. Recent research (by Carolyn Jackson of Lancaster University) confirms that boys and girls who are tall and good looking “earn points on the ‘cool’ ladder”.

By contrast, youngsters who do not feel comfortable in their own body may well suffer from poor self-esteem, which can have a negative impact on their engagement with learning. Children can be very cruel about physical difference, as those with disabilities know only too well, and this can provide a focus for bullying.

For understandable reasons, these matters are rarely discussed openly beyond general exhortations to “take a pride in your appearance”. They are very sensitive and personal. The sensitivities relate not only to pupils but also to teachers, whose appearance is often subject to adverse comment by youngsters. Thus to raise explicitly questions to do with appearance might simply lead to ridicule on all sides.

Indeed, I suspect one of the reasons the makeover programmes are so popular is that they contain a humiliation element. The “experts” draw attention to the least attractive features of their subjects - the wrinkles, the bad teeth, the sagging tummy - and the camera captures them from the most unflattering angle. Of course, this is justified on the grounds that an honest appraisal of the problem is necessary before an improvement plan can be devised.

But, although the programmes may be tasteless and shallow, they do highlight the connection between body and mind. The subjects talk about their transformation in terms of liberation, of giving them the opportunity to change their lives and express their real selves.

What is misleading is that the process is presented as magical and easy.

What is needed is a much more subtle exploration of the relationship between self-worth and real human values.

Walter Humes is research professor in education at the University of Paisley