Thousands of British children are going to school hungry every day, while the country faces an obesity and dietary crisis that is costing the NHS £6bn per year. The numbers speak for themselves: Britain has sleepwalked into a diet crisis, with unaffordable social and economic implications.

This is a multi-faceted crisis that demands an equally substantive set of solutions. There is, of course, nothing wrong with, for example, Andy Burnham, shadow health secretary, proposing a cap on sugar levels in cereal as he did at the beginning of the year. The argument could be sound, but even if you believe it will be effective, it amounts to a prescription of medicine for a patient that requires major, and immediate, surgery.

Politicians could pick and win a hundred battles with the food industry, but if they are not strategically fought, they will still lose the obesity war.

The OECD estimates that only Greece and Italy have a worse obesity problem among children than Britain. And it goes without saying that the obese children of today become the long-term care needs of tomorrow, burdening the NHS with an obesity caseload it can ill afford to service.

To date, efforts to combat this problem have been frustratingly fragmented. Charities including Magic Breakfast and Kids Company are tackling head-on child malnutrition by bringing free meals to schools. On a broader level, the NHS is seeking to drive cultural change through its Healthy Start vouchers scheme, supported by the work of groups such as the Food for Life Partnership.

This is all valuable work without which many more children would go hungry on a daily basis. But to reverse the long-term trend Britain needs a more coordinated, comprehensive and crucially, long-term, strategy, one with the active backing of government and policy-makers.

Our relationship with food has veered badly off course. Children aren't being taught where food comes from, the national curriculum has largely abandoned cookery and nutrition, and salt-laden ready meals are pushing cooked-from-fresh off kitchen tables across the country.

There is a wide appreciation of the dietary crisis we face as a nation, but at present, the good intentions, protestations and public statements of politicians, food manufacturers and nutritionists are not scratching the surface.

Not when over a third of 11 year-olds are classed as overweight or obese. Not when we are facing a future where half the nation's adults, and a quarter of its children, could be obese by 2050.

This is, needless to say, a recipe for disaster. To avert it, we need a strategy that is long-term, far-reaching, and that identifies and combats the root causes of the crisis we face.

This must start today and it must start by focusing on children under-five. These formative years shape the tastes and habits that will last a lifetime; a failure to get it right at this crucial stage invariably has long-term consequences, exactly the pattern that has led to the crisis we now face.

Ensuring a healthy diet is the first stage, but there is a more fundamental need to encourage the youngest children to have a positive relationship with food.

With food, the fundamental truth that people fear what they do not understand holds true. Research by Ella's Kitchen, the organic baby food company I founded seven years ago, has shown that toddlers who are encouraged to play with new foods, and explore them through sight, sound, touch and smell - as well as taste - are more willing to try vegetables.

Fundamental to this is getting cooking back on the curriculum. YouGov research commissioned recently found that 93% of parents believe knowledge of how to cook positively influences healthy eating. 87% of the same parents called for cooking and food education to become a compulsory part of the national curriculum.

While schools have a central role, politicians and the food industry must play their part. Today I am launching a new campaign, Averting a Recipe for Disaster, which calls for a cross-party, 25-year plan to improve nutrition for under-fives. We are asking all major political parties to include a commitment to this end in their 2015 election manifestos.

We have reached crisis point in how we eat as a nation - young and old. The imminent danger is that, as a generation divorced from real knowledge about its food, we create nutritional norms and expectations that will prove irreversible. We have already reached a point where the culture will take decades rather than years to overturn. The important thing is that we begin to work on this together, now.

Paul Lindley is founder and CEO of Ella's Kitchen, which today launches the Averting a Recipe for Disaster campaign: www.avertingarecipefordisaster, @AvertADisaster

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