LONDON — Changes in the way the United Kingdom produces and processes food are needed so the nation can continue to enjoy healthy, affordable food in the decades ahead, said Hilary Benn, secretary of the Department of Environment, Food and Rural Affairs, as he announced the country’s first food-security assessment.

According to the assessment, the U.K. is doing well in many areas that make up a secure, sustainable food system, such as a diverse food supply, which includes the U.K. production and distribution system. The main challenge will be to ensure the sustainability of the U.K.’s food supply.

Reducing greenhouse gas emissions and adapting to a changing climate in the U.K. and overseas that will affect what food can be grown and where and how it can be grown are critical for the U.K. "Last year, the world had a wake-up call with the sudden oil and food price rises," Mr. Benn said. "While we know the price of our food, the full environmental costs and the costs to our health are significant and hidden. We need a radical rethink of how we produce and consume our food.

"Globally, we need to cut emissions and adapt to the changing climate that will alter what we can grow and where we can grow it," he added. "We must maintain the natural resources — soils, water and biodiversity — on which food production depends. And we need to tackle diet-related ill health that already costs the N.H.S. and the wider economy billions of pounds each year.

"And because we live in an interconnected world — where the price of soya in Brazil affects the price of steak at the local supermarket — we need to look at global issues that affect food security here," he continued. "That’s why we need to consider what the food system should look like in 20 years, and what must happen to get there. We need everyone in the food system to get involved — from farmers and retailers to the health service, schools and consumers."

"Our food strategy will need to cover all aspects of our food — production, processing, distribution, retail, consumption and disposal," Mr. Benn said. "And that includes the impact on our health, on the environment and future productivity and on how we deal with food waste."