APPARENTLY it is beach season. That goes for social planners too it seems in so far as the fat cops are back to battle the obesity “epidemic”.

In fairness, I should not use those scare quotes because chubbiness — generously defined — really is an epidemic and not simply the impression of Beltway policymakers who have seen one too many Ruben-esque woman or Jabba the Hutt-ish lad groaning across the sand on tiny legs like a prehistoric mammal making its first awkward steps out of the primordial ooze.

From 1960 to 1980, about 14 per cent of Americans were regarded as obese. Since 1980 the proportion has more than doubled to 30 per cent, and the percentage of overweight kids has almost tripled from 5 to 14 per cent. Though genetic predisposition is the primary cause of obesity, we cannot blame all this excess flesh on our genes. The genetics of society changes very slowly, too slowly to explain the bulging American (or British) consumer.

So what are the causes? Suburban sprawl — the unintended outcome of the interstate highway system and urban planning — is making Americans more lethargic because we drive everywhere now. Feminism — ha! — is a culprit because female participation in the workforce has contributed to a decline in home-cooked meals. One study found that an increase in the hours worked by mothers can result in up to “one third of the growth in obesity among children in certain families”.

Another villain in this story is technology. Sure, microwave ovens save scarce time for working mothers and potheads but they replace balanced meals with timely but tasty fatty food. And, of course, there is the computer, which encourages sedentary living. When I joined the “new economy”, as the founding editor of National Review Online in 1998, I got so big that smaller pundits started to circle around me in an elliptical orbit. It did not help that this career change coincided with a technological breakthrough which enabled large amounts of extra cheese to be smuggled into the crusts of pizza. Thank goodness that the bleeding hearts in the 1990s failed to give free computers to every poor child. How much fatter would kids be today?

But the most hilarious public policy backfire comes in the form of cigarettes. They might cause cancer but they also curtail appetites. It turns out that the campaign to get people to put down cigarettes has had the unintended consequence of getting them to pick up Krispy Kremes. In an article on the economics of obesity in the latest issue of The Public Interest, Inas Rashad and Michael Grossman report that “each 10 per cent increase in the real price of cigarettes produces a 2 per cent increase in the number of obese people”.

Now, as a conservative, I love these unintended consequences. The fact that life is more complicated than the ability of social planners to anticipate is always a relief to those who want to keep social planning to a minimum.

What is more dismaying is the inability of the nanny-staters to realise that they are always learning the wrong lesson. They keep “solving” problems by jumping on the biggest bump in the carpet and are shocked when new bumps appear elsewhere. They conclude that they should have more authority to solve more problems.

The argument that risky or unhealthy behaviour is the State’s business because the State has to pick up the tab is a licence to regulate everything and anything, from driving to sports to sex, indeed life itself. In some cases, the desire for state intervention is a disguised form of puritanism which refuses to accept that others will live “dirty” lives if they are free to do so. The rationalisation that the public has to pay for the health problems of heretics is merely a convenient excuse. After all, cigarette smoking arguably saves money because it results in people dying before they start collecting their old-age benefits.

“The socialist society”, wrote the philosopher Robert Nozick, “would have to forbid capitalist acts between consenting adults.” Well, what would the “healthy society” have to forbid?

Consider what one public health advocate wrote in The New England Journal of Medicine: “Both healthcare providers and the commonweal now have a vested interest in certain forms of behaviour, previously considered a person’s private business, if the behaviour impairs a person’s ‘health’.” The Hitler Youth health manual was more direct: “Nutrition is not a private matter!”

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