To stem the spread of obesity, we must study the web of commercial interests and strategies driving it, says Jonathan Wells.
Pelotas is a South Brazilian city of marked economic contrasts. At the roadside, thin ponies pull battered carts past bicycles. Along the thoroughfare, motorcycles and smart new cars zoom past them. Some people live in shacks made from plastic bags, others in mansions with yachts moored at their garden's edge. Away from the city centre, small stores still offer cheap staples and vegetables. But closer to the centre, a large supermarket has opened, with an escalator leading up from the car park.
The city, where I contribute to epidemiological research on obesity, is also undergoing a marked nutritional transition. In Brazil, between 1973 and 1996, obesity increased from 2.4 to 6.9 per cent in men and from 7.0 to 12.5 per cent in women.
In simple terms, obesity arises when people consume more energy than they expend, either by eating too much or exercising too little. But obesity remains difficult to counter, and hundreds of research papers have been written on tackling it, mostly from high-income countries. Such studies can easily measure dietary intake, physical activity, and obesity status by simple methods (questionnaires, measuring weight and height) or, nowadays, with sophisticated state-of-the-art body movement recorders and stable isotope probes. Yet obesity becomes ever more prevalent.
It's undoubtedly true that economic and cultural transitions affect dietary intake and activity levels. If we measure these changing circumstances, we can see the impact of the growing 'obesogenic niche'—the sum total of environmental factors which collectively predispose to excess weight gain. The problem is that such research risks being simply a witness to the process, telling us what is happening without explaining why. For scientists, the 'why' should be just as important as the 'how'.
What is really driving the obesity epidemic is not increased dietary intake, or decreased activity levels, but the web of economic strategies and commercial interests that cause individual people to change or maintain certain behaviours. The way industry understands and manipulates individuals' behaviour is fundamental to the growth of the obesogenic niche.
Heads of industry would probably argue that they are not trying to create an obesity epidemic. Nevertheless, there are enormous profits to be had from obesity. The foods that maximise profit just happen to be those high in sugar or fat. They are cheap to produce, easy to brand and market, and easy to stock in supermarket aisles. And there are numerous ways to encourage people who are pre-obese to buy these foods.
Sedentary behaviour is also profitable, and encouraged by industry. A moped is more glamorous than a bicycle. A new computer game will re-invigorate peoples' interest, but not their bodies.
Until now, obesity research has concentrated on measuring the numbers of obese people, and attempting to identify the predisposing risk factors. This tends to identify individual behaviours, but not the push and pull factors that encourage or oblige people to display them. We can count the number of hours spent in a car or playing video games, but if we don't understand comprehensively why the car was used or the game was played, efforts to tackle obesity are doomed to failure.
Every new moped or litre of petrol sold, every new supermarket product purchased, is one more small step along the economic transition — and one more turn of the screw by the profit-led industries. These industries need people to indulge in obesity-causing behaviours in order to achieve their quarterly targets. Until commercial practices become the target, first of research studies and then of interventions, we are likely to retain our role of documenting, rather than truly understanding and preventing, the obesity epidemic.
Understanding the obesogenic niche, rather than what happens to the people in the niche, is an urgent but relatively ignored priority. The kind of research needed to probe this issue is very different from conventional biomedical research. Ideally, researchers should have expertise in the same skills that the companies use to maximise their profits — advertising, economics, and forecasting social trends.
Public health scientists need to take on commercial companies at their own game. Perhaps researchers should begin by measuring the same outcomes that companies use to maximise their profit. If the company knows how to sell more biscuits, health researchers need to know how to achieve the opposite.
As yet, governments have been very reluctant to go on the offensive against commercial interests, because the two parties are interconnected. With substantial tax revenues deriving directly from corporate profits, the financial risks to national economies are obvious.
At the simplest level, only when the cost of treating obesity and its co-morbidities exceeds the tax levied from the obesogenic companies is there an economic logic for taking action. Something similar has already happened with smoking in Europe. A more sophisticated approach suggests it would be prudent to act before this tipping point is reached. Obesity is so difficult to treat that prevention is the crucial target.
Maximising profit and incessantly maintaining economic growth are central to the western industrial economic model. This is our mode of capitalism, and the same model is driving the nutritional transition. As countries are absorbed into this model and pass through the transition, an increasing proportion of the population are drawn into new behavioural patterns, altering their physical activity and their access to food. And the obesogenic niche is not exclusive to adults, it also affects foetuses, infants, toddlers, children and adolescents. Each stage of the life-course is a target for commercial interests.
Capitalism out-competes other economic systems, as evidenced by its worldwide spread. So on purely economic grounds it is successful. But the costs may be expressed in other currencies, such as the prevalence of hypertension, type 2 diabetes and cardiovascular disease. Capitalism has been studied primarily by economists. It's time health researchers got in on the act.
Jonathan Wells is a reader in childhood nutrition, Childhood Nutrition Research Centre, UCL Institute of Child Health, London.
See Letter to the editor.
This article is part of a Spotlight on Tackling chronic diseases.