High Olympic ideals of promoting sport and healthy living seem completely at odds with Big Macs, chicken nuggets, fries, sugar rich milkshakes and coke drinks. Yet McDonalds and Coca Cola, through sponsorship deals, will be the only food and soft-drink brands advertised at the London 2012 Games, at both game venues and through TV broadcasts to billions of worldwide viewers, including children.

A growing body of organisations, including the London Assembly and eminent voices in the medical profession, who understand the extent and cost of childhood obesity, are calling for companies whose products are associated with obesity, such as high fat, high calorific and sugar filled drinks, to be excluded from sponsorship of sporting events. This call could mark the start of a process similar to that of the tobacco advertising and sponsorship ban in the early 90s. This was also preceded by the medical profession highlighting health problems with calls for stricter laws on the sale and advertising of tobacco products.

Allowing such brands to sponsor international sporting events subliminally links these brands with health, athletes and sporting achievement. Opponents believe this undermines public health campaigns and sets efforts to promote healthy diets back by years. At the UEFA's Euro 2012 McDonalds adverts showed children that they had sponsored walking onto the pitch hand in hand with their football heroes. This advert was clearly targeted at children and designed to cajole brand loyalty. According to the McDonald's website this is part of their work to 'promote sport and physical activity'.

Restrictions on advertising foods high in fat, salt and sugar already exist on children's television and even Walt Disney recently announced a ban on fast food adverts on its television shows (once contractual commitments end). Yet, just as children watched UEFA's Euro 2012 and its ads, the London 2012 Games will offer no protection to children from such brand targeting. It is disappointing that the International Olympic Committee, responsible for the summer and winter Olympics/Paralympics, just extended McDonalds' and Coca Cola's sponsorship deals until 2020, which means the 2014 winter games in Sochi, the 2016 Olympics in Rio de Janeiro, the 2018 winter Games in Pyeongchang and the 2020 Olympics will have their imprint.

On 20 June 2012, at a full London Assembly meeting, a motion which I proposed, calling for a ban on sponsorship of future Olympic and Paralympic Games by companies which produce high calorie food and drink was agreed. The motion urged the Olympic movement to adopt strict criteria for sponsorship of Games which would exclude companies associated with products linked to childhood obesity, urged the Mayor of London Boris Johnson to encourage the organisers of future major sporting events in London (such as the London 2017 World Athletics Championships) to adopt a similar approach, and urged the Government to consider introducing restrictions on advertising and exclusive marketing at major sporting events by such food and drink companies.

A London Assembly report 'Tipping the Scales' estimated that almost a quarter of a million, or one in five children in London, are obese, and based on current trends predicted that half of children will be obese or overweight by 2020. It also found that children most at risk of becoming overweight or obese came from areas of deprivation.

Such concerns are not just limited to academic, public health and some political circles. Which Magazine [June 2012] found that 64% of UK adults they surveyed agreed that sponsors such as McDonalds and Coca Cola undermine the healthy ethos of the Olympics; 60% thought it encourages unhealthy eating and that it makes it harder to tackle obesity and poor diet.

Amir Khan, the youngest British Olympic boxing medalist at the 2004 Athens Olympics, referring to the 1,500 capacity cathedral like McDonalds in the Olympic village, and the largest in the world, said: "The Olympics are a great opportunity to show young people what types of food they need in different aspects of their life. I think this is a mistake"

Professor Terence Stephenson the vice chair of the Academy of Royal Medical Colleges, in April 2012 stated that the Government's voluntary approach of trusting the food industry to cut calories and advise people on healthy diets was inherently flawed and is failing to tackle obesity. He said: "It's very sad that an event [referring to the Olympics] that celebrates the very best of athletic achievements should be sponsored by companies contributing to the obesity problem and unhealthy habits".

With the scale and cost of treating obesity mushrooming, bodies responsible for public health such as the Government, Mayor of London and regulators can no longer turn a blind eye to this blatant marketing of junk food to children. It's time to show leadership and exercise a duty of care to those who are already overweight, obese, or belong to high risk groups who are disproportionately found in the most deprived communities with diets that are frequently limited to unhealthy and highly processed food. Challenging UEFA, IOC and other sporting bodies over their sponsorship deals with companies associated with products linked to childhood obesity is a fundamental and urgently needed step towards curbing the obesity epidemic.

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