Is obesity really a killer?

Posted on May 17, 2016

In his Budget speech in March, the chancellor of the exchequer, George Osborne declared: 'Obesity drives disease. It increases the risk of cancer, diabetes and heart disease – and it costs our economy £27 billion a year; that’s more than half the entire NHS paybill. And here’s another truth we all know. One of the biggest contributors to childhood obesity is sugary drinks...

So today I can announce that we will introduce a new sugar levy on the soft drinks industry.'

Osborne's intervention is hardly the first justified by obesity. From packed lunch inspections - even bans - in schools through to patients being denied operations on the NHS, obesity has long been a cause célèbre for public health campaigners. But new research from Denmark suggests that the problem has been overstated - and that fears about a 'timebomb' of obesity are overblown.

The researchers looked at the risk of death and cardiovascular disease and how they compared to body mass index (BMI) over time. They found there was a clear connection between ill health and obesity in the 1970s, but this effect has weakened over time. Figures from two research programmes were examined: the Copenhagen City Heart Study in 1976-1978 and 1991-1994 and the Copenhagen General Population Study in 2003-2013. Levels of BMI are usually grouped as 'normal' (18.5 - 24.9), 'overweight' (25 - 29.9) and 'obese' (30 or more). However, the researchers found that 'the BMI value that was associated with the lowest all-cause mortality was 23.7 in the 1976-1978 cohort, in the 1991-1994 cohort, and 27.0 in the 2003-2013 cohort.

In other words, the lowest death rates in present-day Copenhagen were among those who would normally be described as 'overweight'. Moreover, there was little difference in death rates between those who be described as 'normal' and those classified as 'obese'. Nor is this the first study to find that the healthiest people seem to be mildly 'overweight' and most obese people are little more likely to be unwell than 'normal' weight people.

It's possible that modern medical interventions have has some part to play in this change. But perhaps the real reason is that healthy people are, in a modern world where food is cheap and always available and work is less physically demanding, just a bit heavier than before. That makes sense - most people in the UK, for example, are either overweight or obese according to current guidelines. In order to link body weight with ill health, we need to move the goalposts a bit. Obesity was unusual in the 1970s, so maybe the few people who were obese had other problems besides being chubby or that caused them to pile on the pounds. Now, obesity is common, with plenty of healthy people having a spare tyre.

The rapid rise in obesity rates may not be such a cause for concern. Most people who are classified as 'obese' are not in fact unhealthy and will live as long, on average, as slim people.

This would be good news were it not for the fact that public health is so politicised today. To admit that the obesity panic is built on sand would be enormously embarrassing to those who have devoted their careers - and gained much prestige - by trying to scare us into believing that being fat is a death sentence.

George Osborne should reconsider his sugary drinks tax in the light of this new research. The tax is flawed in so many ways, most notably that it will have little impact on calorie intake while raising the cost of living for anyone who enjoys these drinks. The tax will do more for Treasury coffers than it will for the nation's health. But now it is becoming clearer than ever that tackling obesity may be unnecessary.

Better still, the likes of Osborne and the rest of the nanny staters should show a little humility and butt out of our personal choices altogether.