The newish minister for public health probably thought she was being sympathetic with her comments about obesity and the poor. But she was really just revealing her prejudices.

Soubry told the Daily Telegraph that "it was 'heartbreaking' that many of the families who were at greatest risk of obesity were among the poorest in the country".

"A third of our children leave primary school overweight or obese... When I was at school you could tell the demography of children by how thin they were. You could see by looking at their eyes. They would be described as 'the skinny runts' because they were not getting the right food. When I go to my constituency, in fact when I walk around, you can almost now tell somebody's background by their weight... Obviously, not everybody who is overweight comes from deprived backgrounds but that's where the propensity lies".

So are the poor fatter than the rest? This page from The Poverty Site suggests that the relationship is more complex than that. The skinniest group is indeed the richest women, no doubt starving themselves in a desperate attempt to stay thin. (What's so healthy about that?) The next skinniest group, however, is the poorest men. The fattest group is the poorest women. So the poorest 20% of society contains the skinniest men and the fattest women. What can we conclude from this? Not a lot.

It is, in fact, the second quintile that appears to contain the fattest men and the second-fattest women. That is, people with relatively little social pressure to stay thin but enough money to eat as much as they want. But in truth, there is probably only two percentage points of difference between the men in this group and the men in the wealthiest group. Income is not a great guide to obesity rates.

It is not obvious that poor people eat a vastly different diet, in terms of the food groups consumed, to the better-off. A report in 2007 from the UK Food Standards Agency, found: "For many foods, the types and quantities eaten by people on low income appeared similar to those of the general population. Where differences did exist, they were often consistent across different age groups." In other words, differences between young and old were more marked than those between poor and rich. Moreover, broad categories of income disguise a wide variety of differences based on education, ethnicity, attitudes to weight, and so on.

Moreover, there is the assumption in what Soubry said that poverty causes obesity and obesity causes ill health. The upshot of this is that poverty causes ill health. Now, it is true that people on lower incomes tend to die a bit younger than the well-off, but putting that down to obesity is misguided. For starters, as mentioned above, poor people differ from rich people in many different ways. But looking at body weight more specifically, mortality rates for everyone from the upper end of 'normal' (body mass index, BMI, above, say 22) and those who are mildly obese (perhaps up to a BMI of 32 or so) are pretty much the same. And that's the majority of the population.

Nor are obesity rates shooting up. The Health Survey for England published its latest figures in December. For children, it noted: "The prevalence of obesity increased steadily in most years up to around 2004 and 2005, and since then the pattern has been slightly different for boys and girls. Among boys the proportion that was obese has remained at a similarly high level, between 16% and 19%, since 2001. Among girls, there was a significant decrease in obesity [my emphasis] between 2005 and 2006, and levels have been maintained at this slightly lower level between 2006 and 2011." In summary, the authors say, rather cautiously: "The lack of significant change in levels of obesity in the most recent five to six years suggests that the trend is flattening out." Far from getting fatter and fatter, kids are at worst no fatter than they were a few years ago and may well have got slimmer.

The real driver for this kind of comment is that Soubry - like many politicians, commentators and activists - believes that because she is well-off, it is her mission to lecture the poor about how to eat and how to live more generally. There is an almost naturalistic assumption of superiority combined with paternalism.

In other times, this would be merely irritating. Maybe Anna Soubry has ambitions to be seen as a straight-talking Tory politician in the mould of Edwina Currie. But today, that paternalistic attitude quickly translates into calls for 'action' - whether it is portion controls, soda and fat taxes, and endless lectures, through to the really authoritarian measures like the removal of children from their homes where obesity is regarded as a form of neglect.

People with low incomes don't need lectures. They could do without being poor, no doubt, but being patronised about their eating habits won't help them one little bit.

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