It will take more than education or legislation to halt the obesity slide, says Tim Lang

As Parliament was being lampooned as a bunch of fat cats over expenses, I spent much of last week in two international meetings reviewing what to do about the world getting fat.

The fury thrown at politicians is for raiding the public purse. There is no fury about obesity because it's down to all of us. Freudians might say we're really angry about ourselves - and jealous. We want our snouts in the trough too. Actually, with regard to eating, we are there.

Although there are gaps in evidence and the number crunchers always want more and better data, both my meetings confirmed how obesity has rocketed worldwide. The tricky bit is what to do about it. Politicians and companies favour 'soft' approaches such as education to fend off 'hard' changes such as controlling marketing or taxing to alter price signals. It's political.

At one level, the problem is clear. We individualise failure when it's systems failure. The food supply has poured out calories. As people get richer, they abandon bikes for cars and replace physical labour with machinery. It's called progress. We aspire to taking life easier.

In the US last month, I helped a nephew plant a small orchard. We were pathetic at digging the compacted New Jersey soil - our spades were like toothpicks. A JCB conveniently working over the road dug us lovely deep holes in minutes, into which we lovingly planted trees, compost and mulch. It's seductive, this kind of progress.

The problem is that, if routinised, this progress has costs. If I drive daily to work and leave my bike at home. If we live miles from work, shops and schools. If we 'choose' sugary soft drinks endlessly. If fatty comfort food is everywhere. If we stop eating meals but graze all day. In fact, if we do precisely what we've been doing - and what developing countries do when they urbanise and westernise. Only Singapore has reversed the fat trend for children, using draconian intervention, but even its 'success' has stalled.

So is there any hope? The problem is complex. No single policy intervention is sufficient. We need to change the built environment and food supply, create new cultural 'rules', learn to talk with each other without stuffing food. We need to redefine progress. It's that or wait for oil shock or war to shake us out of our complacency. Blaming politicians is sport - another thing we watch but don't do.

Tim Lang is professor of food policy at City University.