Alan Johnson, Britain's health secretary, got it right when he called for a national movement to tackle obesity in his Fabian Society speech. He's taken on board the sound advice offered to governments over many years now that to have any hope of stemming the tide of overweight and obesity, you need a societal approach that involves everyone in becoming part of the solution.
No sooner had he spoken than the Advertising Association, trumpeting a publicity package they value at £200m (over four years), declared it would "embed" health messages in commercials and hoped we would all get into shape in time to sit down and watch the Olympics. It sounds so easy, we might wonder why no one thought of it before.
When the government announced it would spend £75m on an anti-obesity advertising campaign, the director-general of the Institute of Practitioners in Advertising, Hamish Pringle, confided with somewhat alarming frankness to the New York Times: "If you just run some advertising and then forget about it, it's going to have zero effect. If we're seeing obesity as a societal problem, it could be a decade before it shows results."
Hamish Pringle got it right. Obesity is a societal problem requiring us all to be involved in long-term solutions (which do involve quite a lot of more complex changes of the type identified in the government's Foresight Report on obesity last year). But if the only thing actually running is an advertising campaign along with Olympic competitors on the TV, the only pounds lost will be from the public purse.
There is ample evidence of what a complicated business it can be trying to deliver health messages. We know that what works usually has a sting in the tail - such as a penalty for not using a seat belt, or smoking in the wrong place - but we also know what doesn't really work.
Almost 10 years ago the BBC ran an short-lived advert-free public awareness campaign called Fighting Fat, Fighting Fit. Recently I questioned a room full of dedicated health professionals at a Royal Society of Medicine obesity seminar to find out who could remember this campaign. No-one, not one could. Not even the image of a 16-stone Dale Winton fronting the "Weight of the Nation" and dieting for Britain emerged from the dark recesses of recent history.
Yet this was the BBC's largest ever health campaign to promote physical activity and at its peak claimed a Barb audience rating of more than 32 million viewers. Of those millions, 265,804 asked for further information, and a mere 34,281 individuals were motivated enough to return registration cards. Not quite sure what happened to them after that, but we know all too well that overweight and obesity continued to rise remorselessly.
Significantly the "weight of the nation" is now reflected in an average BMI of 27.5. That means about half the adult population is well on the way to becoming obese. They may get there well in advance of the Foresight's prediction that more than half the population will be clinically obese by 2050. Even now the "average" man or woman may have undiagnosed weight-related problems with their cholesterol, blood pressure, and insulin levels, which improved diet and activity could counteract with resulting long term benefits.
Since the BBC's campaign, we have seen a remarkable increase in the volume of messages already on TV and in print - whether it's cooking, fitness, documentaries or news headlines. Public awareness is hardly the issue. Transforming the range of food to a truly healthy offer is an issue. A recent industry-wide survey in Europe showed how little in practice is being done, with many of the businesses contacted refusing to take part in the survey because they didn't agree with cutting fat and sugar and salt from their food products. Transforming the environment is also an issue. Public places need to be more walkable, enabling everyone to be more active. Fewer cars, less pollution, more green spaces would help.
The outcome of the BBC campaign is well documented in Health Education Research in an enlightened analysis by Professor Jane Wardle and her colleagues. But there is more recent evidence of what happens if you place too much faith in advertising health messages.
The US government pulled its funding of a five-year physical activity promotion campaign called Verb. This aimed at turning on teenagers to the benefits of motion. "Verb - it's what you do" wasn't quite the catchy Saatchi slogan to fire the jaded imagination of American youth, so Saatchi and Saatchi's $125 million campaign was lambasted for being too vague. Another $68 million was spent to come up with a better advertising campaign which replaced the vague Verb mottos such as "run" and "jump" (aimed at monosyllabic tweenagers) with a more advanced mottos with more words such as "Get out, go play". There was even Yellowball - half a million balls bearing the Verb logo - which children were encouraged to bounce, then pass to a friend to play with, then sit down at a computer to write a blog about how they had played with a ball. Only in America?
What came out of this extraordinary experiment in subsidising lame media messages? Was this the best the advertising industry could offer? A repository of research papers analysing what went wrong emerged in a supplement in the American Journal of Preventive Medicine last month. Using the most upbeat and positive language, a kindly light was shone on the defunct campaign. The Cartoon Network, Nickelodeon, and a zapper full of other channels had carried the ads. Channel One - the commercial station beamed into US classrooms daily - did its bit (between the ads depicting a cavorting Britney Spears selling Pepsi).
The bottom line was that those who saw the ads were more likely to have been a little more active than those who hadn't seen the ads. Were they active enough? Was the change transient or permanent? Five years is too short a time to tell, and the conclusion was that more sustained long-term messaging is needed to have any real impact.
This much is well known to the big brands offering to implant their advertising with health messages. The same brands have benefited from sustained advertising for decades. Compared with the overall food and drinks sector marketing budget, the £200m-worth advertising earmarked over four years by the companies is hardly change from the capucinno. Broken down into less than £1m a week equivalent for airtime across the whole country, it is unlikely to add up to a high exposure campaign.
But the real question many NGOs would like to raise is whether Alan Johnson should be complying with an advertising industry manoeuvre that would tie in public health with their clients' food and drinks brands. Aren't these some of the same companies that fought all efforts to persuade Ofcom to adopt a 9pm watershed on children's advertising, who continue to see children as legitimate targets, who don't really want consumers to have the plain choice of traffic light labelling because it makes the high fat, sugar and salt content all too obvious?
It isn't really acceptable, as many of the companies' products lead to consumption that is far from balanced – skewed by a heavy load of cheap fat, oil and sugar – or a tasty overdose of salt. If there is broad support from industry to be part of the solution, let the support be unbranded. When it comes to public health, campaigns need to be seen to be independent to retain the public's trust. But let's also be clear about what kind of collective national movement is needed alongside efforts to persuade individuals to change their behaviour.
There must be a movement by companies, to make healthier choices over the products they make available. There needs to be a movement to tailor environments to favour people and public transport. Most of all there needs to be a movement to protect younger consumers, and that must not mean fudging the issue of health. We are all involved in becoming part of the solution, especially in grappling with the challenge of reducing childhood obesity. It takes a village, or nowadays the global village, to raise our children.