Foresight about obesity

Current figures from the Health Survey for England highlight that almost a quarter of our adult population are clinically obese.  Added to this, 13% of girls and 15% of boys aged up to 11 years also have a body mass index of 30kg/m² or more.  The recent Government Foresight report on obesity, which took a long ranging view of the public health problem, estimated that by 2050 we could be facing a society where 60% of adults are obese if nothing is done to curb the current trend.

Most are well aware of the simple fact that too much energy in against too little energy being expended will result in weight gain.  However in today’s environment, managing this energy balance is becoming increasingly difficult.  People don’t choose to be overweight or obese. The Foresight report formally recognised, for the first time, that in order to tackle the increasing levels of obesity there must be sustainable action at all levels of society which includes government, industry, schools and local communities. This requires complicated and sometimes difficult changes, modifying the built environment, transport systems and food manufacturing.

The Foresight team produced an obesity map (1187 kb) which illustrates all the causes of obesity.  There's no single dominating influence.

The core of the map shows our innate biological mechanisms to acquire and preserve energy which is in turn influenced by numerous determinants including genetic susceptibility, level of recreational activity, the walkability of the living environment, energy density of food, cost of food, levels of self esteem, education and media consumption.

The evidence base for what works in managing an increasing population trend towards obesity is weak.  To date, no country in the world has found a solution, although some promising interventions are emerging.  Ideally, an intervention is going to have to tackle the whole system map at once to really have any widespread effect, and for that to happen, efforts must be achieved across the whole of society. 

Obesity has a life course component, with obese parents often having obese children, who are then likely to become obese adults themselves.  Various family-based approaches are being trialled (Watch It, MEND) within families who are already obese. We await their outcomes.  However it was emphasised in the Foresight report that there is no one point within the life course which has proven to be particularly successful for intervening: people of all ages can be persuaded to change their behaviour. 

Evidence from another great public health issue, smoking, show us that there is a long lag time between obtaining research evidence about the harmful effects of smoking and the action taken in terms of behaviour change, public acceptability and interventions.  We may well be in a similar situation for obesity, and it is interesting to note that observers in the smoking campaigns accept that environmental interventions must coexist to support and facilitate behaviour change.

The answers to preventing the estimated increase in obesity prevalence are probably some way off.  However it is now that governments, individuals, families, business and society as a whole needs to be working to provide a coherent systematic approach to tackling obesity.