'We were facing our just desert for all the desserts we had just crammed in out faces'

The message was clear at the adult obesity seminar, where I was surrounded by colleagues in dark suits. They spoke with concern, showed graphs and explained statistics: we were in a big fat crisis.

They painted a grim picture of a nation immobilised by gluttony and laziness. As sure as eggs is eggs Benedict, we were reaping what we had sown; we were facing our just deserts for all the desserts we had just crammed into our faces.

Diabetes rates were through the roof, arteries were clogged, hearts were collapsing under the strain, joints buckled and groaned. What was the solution?

The evidence was clear: calories in, calories out ? simple arithmetic. Eat less, do more.

But something did not make sense. Do people really 'choose' to overeat? What drives them? Why is there a class difference? Does apportioning blame help? Were we hiding our judgements behind medical language and statistics?

I spoke to my fat friends. One, a newly diagnosed diabetic, was clear: 'Type one and type two diabetics are the new undeserving and deserving poor,' he said.

'You have type one, it's an epidemiological reality. You have type two because you ate too much and did too little.' The blame he described was similar to that of 15 years ago when some spoke of the innocent and deserving victims of HIV/Aids.

My informants struggled to believe that even the most empathetic thin person could understand. 'It is as if it is acceptable to pass judgement. If you are fat you are open to public scrutiny,' said one.

Another said that 'you look like you've lost weight' was a powerful statement and a clear judgement. She said: 'A thin person said I looked more like them. I must be worth something. After all, I have conquered my weaknesses. How fabulous!'

Her feeling was that this unwanted and very common 'monitoring' of people with weight problems was intensely personal.

We need food to live, and eating is a social activity, with much of our interaction structured around it. Food can also give a momentary release from stress.

A friend said: 'I eat when I am stressed; it gives immediate comfort'. Another explained that in the absence of other luxuries, fatty food was pleasurable.

Most people know that overeating causes weight gain, but still we get fatter, while interventions tend to focus on outcomes rather than causes. The reasons why people binge eat are seldom addressed.

The human issue is not only calorific intake but also how opportunity interacts with identity and self-worth. Psychotherapist and author Susie Orbach's view that 'fat is a feminist issue' stands - it is also one of class, ethnicity and inclusion.

Where we sit in society affects the actions we take and has a profound impact on how we see ourselves. Arguments about the relative importance of society-wide or individual-level interventions are a diversion. Both are necessary.

Epidemiology paints an important national picture: the opportunities we have affect the quality of the food we can buy. Still, effective measures elude us. Tackling inequality is key but part of the answer lies deep in our psyches.

It is time to expand our knowledge about how our motivations, passions, inhibitions and fears interact with our hunger. Without such an integrated approach, we will not reduce obesity.