Lose weight or lose the bet

Perfectly timed for the New Year resolution season, you'd be forgiven for avoiding this latest series hosted by Dr Christian Jessen. However, this programme takes a positive and very different approach to weight loss for many reasons. Firstly, based on work by Yale economists (Ian Ayres' The $500 diet, and www.stickk.com), a financial cost is wagered by two individuals in competing to reduce their size. The sum wagered is chosen by each individual as an appropriate cost relative to their outgoings. The premise here is that we are more likely to stick to a cause when we are risking a personal, financial loss.

Competitors are pitted against someone with a similar overall fat percentage with very different personal rewards if victorious in greater weight loss. Sacrificing money as the loser to a cause you despise is another incentive to strive for triumph. In this first episode, Harriet, a big-spending, single London doctor wagers £500 with a reward of a racing car track day, whilst Jo, an 'eco-warrior' Mum of two wagers £100 and seeks classes on constructing ecological outbuildings. This contrast in attitudes and values is amusing to watch but also makes sense to further stimulate the competitors to win.

This motivation – as opposed to a diet-based approach – is supplemented by a ban on crash dieting. Participants are required to consume at least 1200 calories a day and are not told how long the 'competition' will continue for (six weeks in reality). This provides a refreshing, more realistic and manageable approach to health promotion and weight loss. Additionally, the aim of the game here is to lose more body fat, as opposed to more biased, overall weight loss seen in so many other shows. The two competitors meet during the process to compare progress and get a motivation boost to win. Although very entertaining, this social comparison and anticipation of reward is also well grounded in research and behaviour change techniques, for example the work of Charles Abraham and Susan Michie.

Some issues remain. As with any health intervention, follow-up is paramount and maintenance is not shown beyond four weeks post-intervention. Additionally, although competitors are matched on fat levels, they are not matched on lifestyle. Viewers may not see a mother of two as equally able to lose weight compared to moderately wealthy single woman (indeed, the single woman is the victor here).

However, this show should be praised for its promotion of a sensible, achievable weight-loss technique with research backing. It provides sound advice on portion control and manageable exercise as feasible changes that can be easily maintained. This is a welcome move away from diet-promotion and a positive start to health viewing for 2015.

- Reviewed by Emma Norris who is a PhD student at University College London and Associate Editor (Reviews)