Fat chance

A study in the Lancet has predicted that more than half of the world’s population will be overweight by 2050. When you consider all the problems facing human civilisation, the idea that most of us could be plump in 25 years time doesn’t sound too bad. Three-quarters of the planet’s population live in Africa and Asia where being a bit tubby might seem a nice problem to have. The health implications of being overweight, as opposed to being clinically obese, are hotly contested and may be negligible; there is even evidence that overweight people live longer than people of a “healthy” weight. Since being overweight correlates with freedom, affluence and economic growth, we should perhaps see the Lancet’s forecast as a target rather than a warning.

It is, however, worth bearing in mind the wretched track record of obesity modelling — and public health modelling in general — before getting too carried away with this forecast. In 2004, The Times warned that “On present trends, half of all children in England in 2020 will be obese.” Aside from a blip during the pandemic, the child obesity rate has not risen since. 

In October 2007, a few months into the smoking ban when the “public health” industry was looking for new dragons to slay, the government published a report by its top experts which predicted that the obesity rate amongst men in England would rise to 36 per cent in 2015 before hitting 47 per cent in 2025. At the time, the male obesity rate was 24 per cent. Today, it is 28 per cent. 

One of the curious aspects of these forecasts is that they always predict that obesity rates will be higher among men than women, despite obesity always being higher among women. In 2011, another study in the Lancet made headline news when it projected that the UK’s obesity rate, which was then 26 per cent, would be well above 40 per cent by 2030. It predicted rates of 35-43 per cent among women and of 41-48 per cent among men, prompting headlines such as “Half of UK men could be obese by 2030”. Perhaps they will be, but it is not looking likely. As the graph below shows, the obesity rate among men is falling further and further behind the projection with every passing year. 

Undeterred by the refusal of reality to comply with its spreadsheets, the authors of another Lancet study upped the ante in 2016 by claiming that the obesity rate amongst women would be 38 per cent by 2025. This looked like a possibility when the rate jumped from 27 per cent to 30 per cent in 2017, but at the last count it was still 30 per cent.

The latest Lancet study focused on the number of people who will supposedly be overweight by 2050. This was a smart move by the authors. It produces a much bigger figure than the obesity rate and is so far in the future that they don’t have to worry about looking silly for a long time. The UK has a lot of overweight adults. As of 2022, 64 per cent of adults in England were overweight or obese, but that figure has only risen by three percentage points in the last twenty years. The Lancet authors reckon it will rise to 73 per cent by 2050. Perhaps it will, but it is not obvious why it should. In 2015, the WHO predicted that 74 per cent of British men would be overweight or obese by 2025. When I described this projection as wild speculation, I was criticised by the aptly named obesity expert Mike Lean who said: “It might actually be sooner: the figure is already 68%.” But it has stayed at around 68 per cent ever since (the most recent figure is 67 per cent).

What is the purpose of pointless projections that are so bad they make the Bank of England look like clairvoyants? The authors of the 2011 Lancet study admitted that their projections were “mere extrapolations from available data” and that “past trends do not always predict the future”. Indeed they do not. In Britain, the big rise in obesity ended twenty years ago and its causes are not fully understood. Rates of obesity have ticked up since 2006, but only gently and inconsistently while rates of overweight have not increased at all. There is no reason to base future projections on the assumption that obesity rates will suddenly start rising like they did in the 1990s. 

The problem for nanny state activists is that although we are told that we are living with an obesity epidemic, but it doesn’t feel like that to any normal, well-adjusted human being. Twice as many adults are obese as they were in the 1980s, but most of us are not and never will be. With the new wave of anti-obesity drugs, it is possible that we have already hit peak obesity, as the USA may have done. The Lancet study mentions drugs such as semaglutide only briefly and dismissively. Despite these drugs coming off patent long before 2050, the authors say that “the sustainability and scalability of anti-obesity medications as a remedy to the global obesity epidemic are doubtful; public health interventions will remain key strategies in tackling the crisis.”

And it is the “public health interventions” that these otherwise worthless studies are written to promote. You might not feel like you’re living in an epidemic now, but just you wait! To slightly paraphrase H. L. Mencken, the business of “public health” is to scare people with an endless series of hobgoblins, most of them imaginary, until they are clamorous to be led to safety. Every trumped up obesity forecast comes with the message that “it is not too late” and that governments have “one last chance” to fix the problem with, er, taxes and advertising restrictions. The Lancet study concludes by describing the rise in the number of fat people as a “polycrisis” that demands “drastic intervention” from the state. According to the BBC, “experts say that if governments take urgent action now, there is still time to prevent what they describe as a “profound tragedy”. 

One of its authors told the BBC that “if we act now, preventing a complete transition to global obesity for children and adolescents is still possible”. How, exactly? One of the few policies mentioned in the study is the UK’s sugar tax, which patently failed to reduce obesity among both children and adults. If that is the standard of the solution, we might as well just embrace the problem.