Fewer cut-price supermarket gimmicks and other measures to help target food waste are central to a new government food security strategy to maintain UK food supplies for the next 40 years.

The strategy is highly critical of bogof - "buy one get one free" - offers and heavily reduced "loss leader" lines that encourage shoppers to buy food they don't need which eventually ends up in the bin. And it calculates that reducing food waste has the potential to cut carbon emissions equal to taking a fifth of the country's traffic off the roads. It also promotes leaner and healthier diets, along with higher crop yields and a move towards accepting genetically modified crops.

The series of reports called Food 2030 had been expected last month but was delayed by internal disagreement within the Department for the Environment, Food and Rural Affairs and foot-dragging over measures that would potentially be unpopular with voters.

Launching the strategy the environment secretary Hilary Benn said: "Last year the world had a wake-up call with the sudden oil and food price rises, but the full environmental costs and the costs to our health remain significant and hidden. We need to tackle diet-related ill health that already costs the NHS and the wider economy billions of pounds each year.

"We need everyone in the food system to get involved — from farmers and retailers to the health service, schools and consumers. Our strategy needs to cover all aspects of our food — production, processing, distribution, retail, consumption and disposal."

It was welcomed by some food specialists who argue that government must provide a brake to consumer-driven market forces. But there was criticism that action with real bite, including curbs on the power of supermarkets over suppliers, and carbon emissions from farming, remained too vague.

There was also frustration that the government was still producing policy strategies and consultations a year on from a major report commissioned at the height of global food price rises from the Cabinet Office called Food Matters. Many felt the new strategy did not include enough substantial changes.

Meredith Alexander, head of food policy at the charity ActionAid UK, said: "The government launched an inquiry into ways supermarkets abuse their market power in May 2006. Three years later, they are only now considering whether or not to actually do something about these bullying practices that contribute to poverty wages overseas."

Professor Tim Lang of City University, a specialist on food policy and member of the Sustainable Development Commission, said: "The issue is how radical or slight will changes for consumers be, and how soft or hard will the policy changes be?

"It's good to see Defra at last championing the view that the UK's food system needs to become very different. But I predict that some very uncomfortable and unpopular decisions will lie ahead for governments in coming years.

"The dominant policy language of recent years has centred on markets, choice and consumer sovereignty. These are too simplistic now. Politics needs to move fast."

Apart from targeting wasteful supermarket offers the reports also promise further action on reducing "tempting" packaging and encouraging restaurants to highlight calorie counts. Food waste in the UK is currently running at average of £420-worth per household, rising to £610 in families with children.

Benn also said that food producers in Britain would have to adapt to climate change, and perhaps grow crops in different areas where they were previously difficult to grow. The report warns that the face of the countryside will have to continue to change to guarantee food security, with GM crop experiments part of the strategy.

"We need to think about the way in which we produce our food, the way we use water and fertiliser," Benn said. "We will need science and we will need more people to come into farming because it has a bright future." He added that global food production had to increase by 70% to feed a world population of 9bn in 2050.

The National Farmers' Union welcomed the strategy's 'joined-up' approach, involving all government departments linked to food production, including the Treasury. NFU president Peter Kendall called for a similar improvement in co-ordinating food research, as well as monitoring GM's effect on the animal feed market as well as pig and poultry production.

He also appealed for a level playing field on sustainability, with strict measures applying to imports as well as home-grown food. He said: "It would make no sense to insist that our production was sustainable but increasingly rely on imports that are not."

Dr Tom MacMillan, executive director of the Food Ethics Council, complimented Defra on "taking a systematic approach to assessing food security" and getting on with the job. But he questioned whether the department had enough clout to tackle wider issues involved in food waste and poor diet.

"For instance, a big factor in food insecurity is income inequality, and you can't crack that by fiddling about with food prices. It calls for better social protection in the UK and internationally," he said. "Another big question mark is over climate change. One of government's most important commitments in Food Matters [a government report published in July 2008] was to push for European climate agreements to take account of methane and nitrous oxide from farming, yet so far all that's happened is a seminar with the French.

"To achieve its aims, the department needs a stronger mandate from the government."

David Adam

Hilary Benn yesterday reignited the debate on growing GM crops in Britain when he suggested the controversial plants could contribute to increased food security. He said: "If GM can make a contribution then we have a choice as a society and as a world about whether to make use of that technology."

GM: feeding the world with science

No GM crops are grown commercially in Britain, although several varieties are farmed extensively in mainland Europe, the United States and elsewhere. This is less down to UK government policy than a reluctance among seed companies to apply for the relevant permits, given the high-profile backlash in Britain against GM food a decade or so ago.

Ministers have never ruled out GM in the UK and a series of comments from inside Whitehall in recent years have prompted speculation that a new industry charm-initiative is preparing to sprout.

In 2008, then environment minister Phil Woolas, said Britain was rethinking its position on GM due to a "growing question" of whether it could help feed the developing world.

Industry bodies have also used the recent food crisis as leverage, though Martin Taylor, head of GM firm Syngenta, told the Guardian last year: "GM won't solve the food crisis, at least not in the short term".

David Adam

From allotment to table in 50 years

With the appetite for home-grown food growing like, well, bindweed, it is good to see urban balconies and backyards groaning under the weight of courgettes and tomatoes. But with National Allotment Week starting today, it is hard to see how the government can meet the demand.

The waiting list in Camden and Islington for an allotment now stands at a staggering 40 and 25 years respectively. With more than 80,000 people nationwide facing an average three-year wait, this isn't all due to middle-class demand – or the Observer Organic Allotment. Research released today by home insurance firm LV shows that 56 per cent of allotment users use their plot to save money, while more than a third do so because of concerns about pesticides.

London food czar Rosie Boycott has promised 2012 new plots by (you guessed it) 2012 and even the venerable National Trust is promising 1,000 new plots in the next three years to help meet this growing demand to grow your own. And if you get your name down today in Camden, your first crop will be ready just in time for 2050.

Allan Jenkins is allotment gardener-in-chief and editor of Observer Magazine