Farmers at present grow enough edible crops to provide every person alive with a daily diet of 4,600 calories. Since this is enough to feed 14bn people, twice the current world population, it would appear that agricultural production is not the root cause of hunger. But a closer look at the figures paints a very different picture. Of these 4,600 calories, 600 are lost between harvesting and processing and another 1,200 are fed to animals. Distribution losses and general waste account for a further 800 calories, leaving about 2,000 calories to be eaten by people.

These figures are averages, of course. Harvests fluctuate with the weather, while the actual breakdown of waste varies from continent to continent. But overall the pattern is clear; in both developed and developing countries, the story of farming and food production is one of loss and inefficiency. What we need is a new paradigm for food and strong new policies on sustainable production and consumption.

One set of options for a new global paradigm is spelt out in a ground-breaking report from the International Assessment of Agricultural Knowledge, Science and Technology for Development (IAASTD). The 2009 report “Agriculture at a Crossroads” says that farming must be transformed at every level and across all regions in order to address the causes of repeated food crises and the environmental costs of agriculture, including the loss of biodiversity, over-reliance on external sources of energy and health problems.

In developed countries, for example, food is generally too cheap, which leads to tremendous waste from harvest to consumption. Industrial food production, from large-scale mono-cropping to factory farming of livestock, is not only unsustainable because it consumes more calories than it produces but because it contributes between 47% and 55% of greenhouse gas emissions.

In developing countries too, traditional agriculture is unsustainable, partly for the same reason; farmers tend to mine natural resources and destroy forests to keep food cheap. And cheap food, wherever it is produced, devalues farming as a profession; it pushes farmers into poverty or other work despite their knowledge of the land and how to work with nature to sustain cultivation being critical for the future.

In both traditional and industrial systems, new policies are needed to encourage farmers to switch to sustainable production practices. The feasibility of these methods has been demonstrated in many instances, so we know what has to be done and how much it will cost (less than the perverse subsidies currently paid to farmers and across the value chain).  The problem is that powerful vested interests are blocking the way.

To reiterate, food insecurity is not a question of agricultural under-capacity. Nor will we find solutions in quick-fix proposals based on fear-mongering about how to feed 9bn people. The problem lies at different levels in different regions, and needs to be tackled accordingly. As well as investment to enable farming to become more sustainable, we need new economic policies to create jobs and break the cycle of poverty and hunger. Cheap food cannot be the solution to world hunger. Food prices must be high enough to allow for sound rural development, and food security must be a matter of national interest.