Wednesday, 18 June 2014

Bradford Council: Restricting fast food operators through planning won't reduce obesity, is probably illegal and is open to challenge


There are proposals in Bradford to introduce restrictions through the planning system on fast food outlets. Below is a report I prepared for Councillors in Medway on the issue. It applies in Bradford too - the policy is probably illegal as it is unsupported by evidence, will not contribute to reducing levels of obesity and is open to challenge by Inspectors and through the courts.

Planning and fast food outlets
Simon Cooke MSc March 2014

There have been calls for the use of planning policy as a tool in public health chiefly in contributing to reducing levels of obesity especially in children. There are fifteen local authorities with ‘supplementary planning policies’ that touch on obesity and food retail, ten of these specifically relating to hot food takeaways. 

Generally these policies focus on ‘exclusion zones’, typically 400m around schools, community centres and leisure facilities. There have been a lot of decisions to refuse where the reasons for refusal include being within such an exclusion zone.

However, while some of these refusals have been successfully defended at appeal, none have cited the exclusion zone as the only consideration in upholding refusal. There is, therefore, no robust planning evidence that these policies are either purposeful or defensible at appeal.
The grounds for introducing policies of this sort are twofold:

  • 1.    A view that, with local authorities taking the lead role in public health, planning policies need to contribute to broad public health strategy
  • 2.    That there is a specific link between what are called ‘obesogenic’ environments, such as the presence of fast food clusters near schools, and rising levels of childhood obesity

It is hard to take issue with the first of these objectives. However, planning policy should be purposeful i.e. it should be able to demonstrate that removing someone’s right to develop will achieve the purpose of the policy. In the case of hot food takeaways near to schools, we therefore need to show a clear link between the concentration of such outlets and childhood obesity. If such a clear link doesn’t exist then the policy does not meet its purpose.

We can see this by looking at comparable policies aimed at promoting all-population outcomes especially in encouraging the reduction of carbon emissions as part of a strategy to combat climate change. In every case where these policies exist there is a specific and measurable benefit – by requiring changes to build quality we can show an exact reduction in carbon emissions. Whatever our view on the value of such requirements, it is clear that the policy meets its purpose of reducing emissions.

Therefore, in looking at using planning policy to reduce levels of childhood obesity, we need to answer two questions:

  • 1.    Is there a good enough evidence base demonstrating a link between the proximity of hot food takeaways to schools and levels of obesity?
  • 2.    How will we measure the impact of the policy on levels of obesity in children?

As a presentation by Medway planners to the Town and Country Planning Association noted:

Evidence base is contested:

‘The use of SPDs by local authorities has not as yet been evaluated and the impact on obesity and other health issues remains unknown.’ Takeaway Toolkit (2012)

‘The literature review overall is entirely unclear and not firm enough to base ANY planning policy changes on.’ [Andrew Lainton, planning commentator]

There is a mixed evidence base with research conducted in the UK, the USA and in multi-national studies. Some find ‘moderate’ links between takeaways and obesity while others find little or no link.

“Exposure to takeaway food outlets in home, work, and commuting environments combined was associated with marginally higher consumption of takeaway food, greater body mass index, and greater odds of obesity.”  Burgoine et al, British Medical Journal 2014

“The obesity epidemic exists among those without significant consumption of or availability to takeaway foods. In a setting of easy availability of food, the obesity epidemic relates strongly to reduced physical activity, but not to consumption of takeaway food.” Simmons et al Int J Obes (Lond). 2005 

Within a population of urban low-income preschoolers, overweight was not associated with proximity to playgrounds and fast food restaurants or with the level of neighborhood crime.” Burdette & Whitaker, Preventative medicine, Vol 38 Issue 1 2004

These results indicate a correlational relationship between both the number of residents per fast food restaurant and the square miles per fast food restaurants with state-level obesity prevalence.” Maddock,  Am J Health Promot. 2004 Nov-Dec;19(2):137-43.

As these studies show the evidence of a link between concentrations of hot food takeaways and obesity is very weak (indeed you could argue it is non-existent).

Perhaps the most striking study from New York not only showed no link between fast food consumption and obesity but actually showed a negative correlation!

When the researchers weighed these children they found something rather interesting. Here are the average body mass index (BMI) figures for each group by frequency of visits to fast food outlets. Bear in mind that a 'healthy weight is 18.5 to 25:

Weekly visits        BMI

Every day:            17.8

4-6 times:              18.3

2-3 times:              19.6

Once:                    20.3

Less than once:     21.4

It seems to me that planners are taking a big risk if they introduce policies that prevent a business from operating purely on the grounds that the presence of that business will contribute to higher levels of childhood obesity.

So the evidence, such as it is, suggests that at best the ready availability of hot food takeaways has a marginal impact on adult obesity (Burgoine et al and Maddock) but that most studies looking at local impact find no correlation between concentrations of takeaways and obesity.

Even if we accept a link (which would be playing fast and loose with the evidence) we still need to be able to show how the planning policy will achieve its purpose – lower levels of obesity amongst children. Most specifically lower levels of obesity among children affected by the decision – those attending the school or other facility within an exclusion zone where a planning permission for a hot food takeaway is refused.

I do not see that there is any way of making this measurement without expensive and intrusive programmes of weighing and measuring children in the relevant school. Moreover the policy cannot affect existing hot food takeaways – unless there are locations where there are no such takeaways within a proposed exclusion zone.

The result of such a policy would likely be that some people would be unable to open a takeaway in their property (with the potential for a negative impact on the economy) but that there would be no measureable or indeed noticeable reduction in childhood obesity.

If we are concerned about child obesity, our focus should be on the factors that contribute to the problem. Here from a French study:

The results show that parental overweight and birth overweight are closely related to the child's obesity at five years of age ... The environmental factors which contribute to child obesity are: southern European origin of the mother, snacks, excessive television viewing and, more importantly, short sleep duration .... A logistic regression model, after taking parental overweight into account, shows that the relationship between obesity and short sleep duration persists independently of television viewing.  Locard et al, International Journal of Obesity and Related Metabolic Disorders : Journal of the International Association for the Study of Obesity

·         Birth weight;
·         Obesity in one or both parents;
·         More than eight hours spent watching TV a week at the age of three;
·         A short amount of sleep - less than 10.5 hours a night at the age of three;
·         Size in early life - measured at eight and 18 months;
·         Rapid weight gain in the first year of life;
·         Rapid catch-up growth between birth and two years of age;
·         Early development of body fatness in pre-school years - before the age at which body fat should be increasing (at the age of 5-6).

What is not present in any of these studies is any support for the idea that an ‘obesogenic’ environment outside the home is a contributor to raised levels of childhood obesity. There is evidence that shows a link between poverty and obesity – this reflects the relative cheapness of energy dense food and especially processed carbohydrates. A related link is between levels of physical exercise and obesity and we know that children from poor families get less physical exercise.

In conclusion, I think that these policies are:

  • 1.    Probably illegal in that they are unsupported by the evidence
  • 2.    Do not contribute to reducing obesity in children
  • 3.    Leave the Authority exposed to challenge by Inspectors and the Courts


1 comment:

Anonymous said...

how about 4. they have no mandate!!!