Alan Johnson today called for a "fundamental shift" in the approach to tackling Britain's obesity crisis and said individuals could not be blamed for the problem.

The health secretary admitted that the government's target of halving childhood obesity by 2010 had been moved back a decade.

However, he avoided blaming the obesity epidemic on affected individuals. Citing the findings of the Foresight report, he said there was no evidence that modern British society was any more gluttonous than previous generations had been.

"Tackling this problem calls for a fundamental shift of approach," he said.

"Many of the areas identified in the report could not be tackled successfully by the government alone. I hope this report begins a national debate if we are to rise to this challenge."

Mr Johnson used a Commons statement to announce that he would set up a cross-governmental ministerial group to tackle the looming health crisis, partly caused by the luxuries of modern living.

However, he stopped short of laying out an action plan in his response to the Foresight report, which concluded that the obesity problem could cost the UK £45bn a year and take 30 years to turn around.

The health secretary said the report predicted that 60% of men, 50% of women and a quarter of children and young people would be obese by 2050 unless action was taken to remedy the situation.

Highlighting the health implications, including soaring rates of diabetes, strokes and heart attacks each year, he said the cost was not to the public purse but was a blight on individuals' lives, adding: "The implications for those that are directly affected are profound."

Small changes, such as companies putting out fruit at company meetings, should be considered among larger, government directed moves such as an increase in sport at schools, he said.

The government has already introduced a minimum of two hours of sport a week and was aiming to increase this to five, he added.

Andrew Lansley, a Tory spokesman, said the report could be regarded as a wake-up call. "The government has been asleep for the last decade while the alarm bells have been ringing," he said.

· Food blog: Rebecca Smithers on the obesity crisis