Slowly, the penny is dropping that future food security requires a shift to sustainable diets. Some see this as a developing world problem - if only the BRICs wouldn’t eat more meat and dairy! This is nonsense. China’s meat consumption has rocketed, but per capita it’s below the US’s. As people get richer, they go through the Nutrition Transition. We did it earlier so cannot blame others who follow. The common challenge lies ahead: how to lower everyone’s impact, eat well, eat less meat, reduce feeding animals on cereals, and prevent huge diet-related ill health bills.

Last week, the UN launched another report urging sustainable diets. Next month, researchers and foundations meet to discuss the research agenda.

A leading researcher said to me recently, we know the problems but no-one’s addressing what to do. In fact, five policy positions are emerging.

The first is that it’s not a problem. Leave it to markets. If UK consumers want to eat as though there are three planets (US five), let them. That’s the Canute position.

” Canute’s position: to keep on eating as if there were three planets”

The second centres on choice-editing, mostly beneath the consumer radar. The strategy is quietly to shave off environmental stresses like CO2 and H2O. But this lowers footprints only so far. Big change requires heavy consumers to cut down.

The third is in civil society terrain. This is to experiment with sustainable diets. Eating diets lower in meat and dairy, with lower carbon and less heavy transport, ticks enviro and health boxes.

The fourth seeks solutions from technology. Sometimes this is wrapped up in pleading for bioscience funds at farm level. It’s a variant of the paradigm that got us into the trouble we’re in: mining resources to raise productivity while jettisoning people from the land and assuming consumers make rational choices. But if anything needs research support, it’s horticulture.

The fifth is illustrated by the EU quietly creating new frameworks. It’s tortoise to Big Science’s hare. It began with the resource-efficient Europe Roadmap. A sustainable food directive is under way. Many welcome it for giving some guidance. But where is the UK government in all this?