If you’re reading this you’re probably thinking what has cross promotional marketing to do with children. Personally when I first heard the term I was thinking what exactly is it?

Simply, cross-promotional marketing is the act of strategically aligning businesses that target the same market but do not directly compete with each other. Whenever two organizations join forces to attract their mutual customers they can more than double the number of prospects they each reach.

For example, in 1996 MacDonalds and Disney signed a ten year deal to cross-promote. Get it? Same market, but not in direct competition and double the reach. A subsequent survey by Eric Schlosser of US schoolchildren found that the only fictional character with greater recognitions than Ronald MacDonald – who had 96% recognition – was Santa Claus. Oh, by the way, MacDonalds operates more playgrounds – designed to attract children and their parents to its restaurants – than any other private entity in the US;

This sort of promotion is also seen with film tie-ins such as Burger King and Toy Story.

Sorry to be a spoilt sport, but given the obesity epidemic - currently 10% of children worldwide are either overweight or obese - it’s time to rethink cross-promotion.

Beware; next time you are out and about, particularly if you have children, you will start to see cross-promotion all around you.

After Christmas and in the run-up to Lent, people are often thinking about New Year’s resolutions and what to give up. One of the most common excesses that people want to address is food. This is the most common time of year to start new diets, exercise regimes and gym memberships, and yet obesity, particularly in childhood, is on the rise. The direct cost of overweight and obesity to the NHS has been estimated at over £3 billion. Inequalities in obesity have been identified between North and South, between men and women, and between social classes, and these inequalities seem to be worse for childhood obesity.

With the big public health problems of our age, whether smoking and high blood pressure, or diabetes and obesity, there are health inequalities, but there are also cheap, simple, population-wide interventions which can save thousands, if not millions, of lives. In the case of childhood obesity, it is not rocket science- healthier diet, less processed food, more exercise, and there are signs that the childhood obesity epidemic is levelling off. However, there is a constant push by device companies and drug companies to offer more complicated solutions which will produce big profits for them in these disease areas, because they affect so many people in the population.

This week’s BMJ includes a randomised controlled trial of a novel computerised device, the Mandometer, which provides feedback to participants during meals to slow down speed of eating and reduce total food intake. The trial ran for 12 months comparing the Mandometer with standard lifestyle modification advice and included 106 obese people aged 9 to 17 years. The Mandometer group had a BMI 0.24 units lower than the group receiving standard care. Not only does this seem a paltry difference in BMI; two of the study authors own 60% of the company which produces Mandometer, and so it is unsurprising that they found a positive effect for their device. It is hard to envisage a world where this device is going to be widely used or where it is going to make any difference to childhood obesity. If widely used, such devices will at best only increase the socioeconomic inequalities which already exist in childhood obesity. Surely the simple, population-wide policies of encouraging more exercise and better diet should be promoted instead?