George Monbiot blames the government for rising obesity levels – there’s a simpler explanation

George Monbiot has written a curate’s egg of an article for the Guardian on the subject of obesity. Struck by the near-total absence of fat people in a photo of Brighton beach in 1976, he wondered whether the rise of obesity in the intervening years was the result of more calories in or fewer calories out.

What he discovered came as a shock to him. His first revelation will be no surprise to readers of this blog: calorie consumption has fallen over time. Thanks to the National Food Surveys, we have a treasure trove of information going back to 1940. It shows that the average Briton was consuming more than the modern recommendation of 2,500 calories a day during the war. This rose after 1945, peaking in the 1960s, and falling thereafter. Average daily calorie consumption fell from 2,850 in 1970 to 2,560 in 1980. By 2011, it had dropped to 2,269. Figures from the National Diet and Nutrition Survey, which began in the 1980s, tell much the same story.

These surveys have raised concerns about mismeasurement. We know that people under-report what they eat and that fat people under-report more than thin people. In 2016, Public Health England hired the Behavioural Insights Team to look into this. Sure enough, they found evidence that people under-reported calorie intake and that the scale of under-reporting had risen over time, but even after correcting for this, they found that we are consuming fewer calories than we did in the 1970s.

All the evidence points in the same direction. Average calorie consumption – and, indeed, sugar consumption – is lower today than it was in the 1970s when obesity was relatively rare. The only way to deny this is to dismiss decades of research as worthless rubbish. That is not a good look for an empiricist and it is to Monbiot’s credit that he does not do so.

If we are not consuming more calories then the rise of obesity must be due to us burning fewer calories off, right? Not so fast, says Monbiot. He offers evidence that children are doing just as much exercise as ever and that people in poor countries burn the same number of calories as people in rich countries.

So what is the answer? Alas, this is where Monbiot’s article descends into gibberish. If you’re familiar with his oeuvre, you won’t be surprised to hear that the blame lies with those nasty corporations. They use advertising to ‘overcome our resistance’. They ’employ an army of food scientists and psychologists to trick us into eating more than we need’. They ‘discovered our weaknesses and ruthlessly exploit them.’

This is all standard Guardian banter but it doesn’t make any sense in the context of Monbiot’s article. It is almost as if – perish the thought – he decided what his conclusion was going to be before he began his research.

Even if everything Monbiot says about ‘Big Food’ is true, even if he is right when he says that ‘the opportunities to load our food with sugar have boomed’, we are still faced with the inescapable fact that we are consuming less sugar and fewer calories than we did in the glorious summer of 1976. As far as I can tell, Monbiot does not subscribe to magical thinking about particular types of calorie. His explanation therefore explains nothing.

So what is the real answer? There are factors that Monbiot does not mention, such as the rise of central heating and the decline of smoking, which are likely to have had some effect, albeit only on the margins. It is possible that future research will find that some unsuspected biological factor has also played a role. And it is important to remember that averages do not tell the whole story. It would be an ecological fallacy to assume that everybody is eating less just because average consumption has fallen.

Nevertheless, it is puzzling, to say the least, that the rate of obesity could rise so sharply if calorie consumption has fallen and people are as physically active as they have ever been. But this is where Monbiot makes his mistake. Physical activity has declined and his slivers of evidence to the contrary do not stack up against the facts. Public Health England says that levels of physical activity have dropped by a quarter since 1961. The World Health Organisation says that western countries have seen ‘decreased physical activity levels due to the increasingly sedentary nature of many forms of recreation time, changing modes of transportation, and increasing urbanization.’ Harvard School of Public Health says that: ‘Physical activity levels are declining’ and that ‘this decline in physical activity is a key contributor to the global obesity epidemic’.

Physical activity is not always easy to measure and it is often confused with leisure time exercise, but there should be little doubt that we are burning off fewer calories than ever in our day to day lives.

Britons are walking less (from 255 miles per year in 1976 to 179 miles in 2010) and cycling less (from 51 miles per year in 1976 to 42 miles in 2010). This is true of both adults and children.

Unsurprisingly, people who drive to work are fatter than those who go by foot or by bicycle. And when we get to work, we are more sedentary than ever, as Tim Olds notes:

In the 1960s, half the jobs in private industry in the United States required at least moderate-intensity physical activity, compared to less than 20% today.

Work in factories and farms has given way to office work, and that has amounted to over 400 kilojoules less each day that adults expend at work. This difference alone results in a weight increase of about 13 kilograms over 50 years, which pretty closely matches actual changes in weight.

Only 18 per cent of British adults report doing any moderate or vigorous physical activity at work while 63 per cent never climb stairs at work and 40 per cent spend no time walking at work. Outside of work, 63 per cent report spending less than ten minutes a day walking and 53 per cent do no sports or exercise whatsoever.

This trend is confirmed by the National Food Surveys, which occasionally allude to the fact that the rise of office work resulted in people not needing to eat so much. As early as 1962, they reported that ‘energy requirements have decreased in all regions … The decrease in calorie requirements is greatest in Classes A2 and B, and is partly explained by the increasingly sedentary nature of their occupations’. In 1971, they mentioned the ‘continuing decline in energy needs as work becomes less strenuous.’

On average, declining energy needs have resulted in declining energy consumption, but not for everybody. Hence obesity. It is easier than ever to get fat, not because we are eating more but because physical activity has been engineered out our lives. It is trivially true to say that obesity is caused by eating too much, but in relation to what? If we want to understand what has changed at the macro level in the last fifty years to drive up rates of obesity, we must first acknowledge that ‘calories in’ have not gone up. And once we accept that, there is only one credible explanation left: ‘calories out’ have gone down.

  • Grope_of_Big_Horn

    Monbiot is a very confused individual. Before the EU referendum he wrote a beautiful piece eviscerating the EU’s Common Agricultural Policy, and then came reluctantly to the conclusion that it was still worth remaining an EU member.
    George, if you’re reading this, the CAP is the number one budget item. The number one feature of the Customs Union is to protect the people who get the CAP hand-outs from competition. You cannot intelligently endorse staying in a club unless you are aware of its primary fiscal purpose and are supportive of it.
    He’s then written this week’s piece about big bad food providing corporations and has failed to mention that as a member of the EU we subsidise the landowners in Europe who produce sugar beet and other carbohydrates which go into processed food. He then omits the generational inequality where we apply a sugar tax to trendy sugary drinks which are overwhelmingly consumed by the young, but for the oldsters’ biscuits with their tea there is no sugar tax and they are even VAT free.
    Monbiot has a very messed up brain who has gone total Guardian. Still writes lovely accessible prose though.

  • Flippant

    The records of caloric intake given by people to researchers, should be likened to a doctor asking you
    how many units of alcohol you drink..yeah right

    Doctors double what you say; fat people lie and lie about what they eat becasue it’s embarrassing you only have to
    look at the endless fat loss telly stuff to see recidivistic people who can’t stop scoffing pies and chocolate
    they almost always confess to cupboard full of crisps and chocolate tumbling out of the kitchen unit.

    I am afraid like all habits, the user is a fibber

  • Dan Holdsworth

    The biggest single item on the energy budget of any person, any mammal or bird for that matter, is maintaining of body temperature. There are a couple of differences between now and the 1970s in terms of this: duvets and central heating.

    We spend a third of our lives asleep in bed. Increase the insulation factor of our bedclothes, and we expend less energy to keep warm; add in central heating (as a child I can remember ice forming on the inside of the single-glazed windows of my bedroom) and the energy needed to keep a person warm all day decreases dramatically.

    I saw a very good experimental example of this a few years ago. We had an outdoor-living cat which had a bed in an outbuilding. Feeling sorry for it, we added a heater to this animal’s bed. The food intake of this cat immediately dropped tremendously as its energy budget decreased from being warm at night.

    • J0hn029

      Interesting, don’t think the missus will be happy with me leaving the windows open tonight then

      • Hermine Funkington-Rumpelstilz

        You should always sleep with an open window. Why would anyone not do that?

  • JonathanBagley

    What struck me was George’s link to the graph showing the very sudden upward trend beginning in 1976. What happened in 1976? Changes in exercise, manual work and eating habits are surely fairly gradual. Is this real or was the data collected differently beginning in 1976?

    • chrissnowdon

      There was no proper data until 1988.

  • Ken

    “It is almost as if – perish the thought – he decided what his conclusion was going to be before he began his research.”

    No! Really?

  • HJ777

    Leaving aside the fact that there are more high calorie foods available cheaply than ever (which makes me sure that calorie consumption has increased), decreasing levels of physical activity are, in part at least, down to government policy.

    This is because virtually everywhere car and bus use is prioritised over walking and cycling, and large lorries are allowed into and through small towns and villages. The level of walking and cycling has dropped dramatically as a result. I live just over a mile from my local town centre and I only ever walk or cycle in but I am one of a very few exceptions. Big new car parks have been built and a major road change has been introduced just to make driving in easier. Nowhere have the interests of pedestrians or cyclists been considered – it is simply very difficult to walk or cycle in safely unless you are an agile adult, so most people do not.

    Contrast this to the Netherlands where over a third of urban journeys are by bike. There is much lower car use (but not car ownership) and much lower use of buses. Lorries are generally restricted in residential areas or town centres.

    • J0hn029

      Never compare the UK to the Netherlands. The entire country is flat, and has been engineered almost entirely for the bicycle with their own lanes and traffic lights. Here we have lots of hills (apart from places like Cambridge) and a 6 yard cycle “lane” on the edge of a pavement in order to satisfy EU law.

      Public transport is also ridiculously cheap over there and very frequent, oh and shock horror, it’s all integrated!

      • HJ777

        Why shouldn’t I compare? Most of our towns and cities are relatively flat and my point is that they have good cycling facilities where we cater almost exclusively for drivers. Switzerland has three times the rate of cycling of the UK. Is it flat?

        I don’t know hat you are referring to when you say “a 6 yard cycle “lane” on the edge of a pavement in order to satisfy EU law”. I’ve never seen anything of the sort and in any case, both the UK and the Netherlands are in the EU.

        Fewer people use public transport in the Netherlands, especially buses.

  • HJ777

    Christopher Snowdon needs to read the Behavioural Insights report again – properly this time.

    It effectively says that even the ‘corrected’ calorie intake figure must be too low because it is below the level needed to maintain weight either at minimum possible activity levels or (to an even greater extent) at likely energy expenditure levels and that lack of physical activity alone cannot account for rising levels of obesity. Compare the two graphs and you will see that this must be the case.

    Christopher Snowdon is simply misreading, or perhaps not reading, the data.

  • Thomas Jones

    Obesity is caused by consuming more energy than is required. If we put less in our mouths then fat hasn’t got a chance in hell. People are clearly eating, and drinking more than they did a few decades ago, and apparently we are exercising more than ever.
    The key to avoiding and fighting obesity is CICO..Calories in, calories out. No one puts the food in your mouths, you do!
    There is no secret or mystery to weight loss, stop being greedy!