Buy local produce and save the world: why food costs £4bn more than we think

Every major supermarket spends millions of pounds a day making sure their warehouse-sized stores are brimming with products ranging from Kenyan mangetout to Scottish potatoes.

Every major supermarket spends millions of pounds a day making sure their warehouse-sized stores are brimming with products ranging from Kenyan mangetout to Scottish potatoes.

But the true costs of producing and transporting food to and from the supermarket shelf are far greater than any checkout receipt suggests. A study that tries for the first time to calculate the real size of our food bill has found we are indirectly spending billions of pounds a year extra on food without realising it.

Government statistics show each person in Britain spends an average of £24.79 a week on food. But if the hidden costs of transport and the impact on the environment were included, this bill would rise by 12 per cent, the study found.

Professor Jules Pretty, of Essex University, and Professor Tim Lang, of City University, in London, said another way of looking at the problem was to assess the national savings that could be made if everything was done differently.

They reckoned more than £4bn a year could be saved if farmers grew organically, farming subsidies were abolished and if consumers shopped for local produce, preferably on their bikes. The issue centres on the concept of "food miles" which refers to the distance travelled by produce from farm to fork.

The scientists tried to assess the added expense of bringing food from around the UK and the wider world to the typical British dinner table. By analysing foodstuffs, farming methods and transport policies, professors Pretty and Lang found that if all of our food came from within 20km (12.4 miles) of where we live we could save £2.1bn a year in environmental and congestion costs.

They also found that if shopping by car was replaced by bus, bicycle or walking, these savings would amount to a further £1.1bn. And if all farms in Britain were to follow organic principles, the costs to the environment would fall from £1.5bn a year to less than £400m, a further saving of £1.1bn. "Food miles are more important than we thought and buying local is more important than buying green," Professor Pretty said at the Science Media Centre in London. "It's better to buy a local lettuce than an organic one from the other side of Europe."

The study, in the journal Food Policy, found 28 per cent of all freight on the roads of Britain is agricultural produce. Not only is more food being transported by road - up by 23 per cent in 20 years - but it is being carried 65 per cent further than it was in the 1980s.

In effect, Professor Pretty said, Britons are paying three times for their food: once at the supermarket till, twice in costs to the environment and the third time in farming subsidies.

The study found the "air mile" costs of importing food from abroad were trivial compared with the huge costs of transporting home-produced food around the country. "The most political act we do on a daily basis is to eat, because our actions affect farms, landscapes and food businesses," Professor Pretty said. "Food miles are much more significant than we thought, and much needs to be done to encourage local production and consumption of food."

Professor Lang said he invented the concept of food miles 15 years ago to articulate the problem of hidden costs of agricultural production. "How far food travels is becoming more important for policy makers and consumers alike," he said. "For example, fruits and vegetables travelling long-distance or short-distance may deliver similar nutrition or look the same, but environmentally they are poles apart."

One way to tackle the problem would be to force supermarkets to label food with the distance it has travelled. "Supermarkets should put food miles on products," Professor Lang added. "They have invested billions in a hyper-efficient, just-in-time system of food distribution, and actually, it's just cuckoo. This is an area where consumers are suffering from an information deficit."

HOW WE OVERSPEND

Environmental cost of farming: £1.1bn a year

If all farms were organic it would save £1.1bn a year. Removing pesticides from water supplies, for example, adds £250m a year to water bills. Other costs range from pollution to losses in soil and biodiversity, and costs in human and animal health, such as BSE and antibiotic resistance. Hidden costs of £1.5bn a year could be cut to £385m.

Environmental cost of food transport £2.1bn a year

28 per cent of road freight is food or produce; 1.6 billion tons are carried 149 billion ton-kilometres. 23 per cent more food than 20 years ago is on the roads and it is travelling 65 per cent further. Each person makes, on average, 221 shopping trips per year with an average length of 6.4km, up from 4km in 1985. £2.1bn could be saved if all food was locally sourced.

Hidden farming subsidy costs: up to £1bn

The average annual cost of agricultural subsidies paid by the UK taxpayer was £3.1bn with an extra £2bn in 2001-04 for the foot-and-mouth epidemic. Until 2004, agricultural subsidies mostly supported production that caused adverse environmental impacts. Some subsidies can improve the environment but without them, subsidies still total £2.9bn a year.

* The average person eats 11.68kg (25.7lbs) of food a week

* Typical weekly food shopping costs £17.26 and an extra £7.53 is spent on eating out

* About 12.2 million tons of food is imported each year and 7.4 million is exported

* Britain exports about 400,000 tons of milk each year, and imports a similar amount from abroad

* The biggest hidden costs of food arise from the rearing of livestock, with beef and veal imposing the largest impact on the environment

* Each person makes, on average, 221 shopping trips a year, covering an average distance of four miles

* Britons spend about £89bn a year on food