Childhood obesity is not at its highest in the most deprived areas of the UK
These findings are contrary to the 'deprivation theory' and question current understanding and interpretation of the relationship between deprivation and obesity in children.
The study, led by Dr Claire Griffiths, with childhood obesity expert Professor Paul Gately, Dr Paul Marchant and Professor Carlton Cooke, investigated the relationship between obesity and area level deprivation, based on where a child lives, in 13,333 Leeds school children over three years. Results showed that children living in the middle-affluent areas had the greatest probability of being obese according to all measures of obesity, with this relationship being more marked in girls.
The Leeds Metropolitan University study took a local level approach and used an area level measure of deprivation* (based on the child's residential postcode) which is novel in the context of obesity studies. The large sample size covering the whole city of Leeds, the reliability of the data (one person took all measurements) and sophisticated statistical analysis techniques** provide confidence in the data reported and may also help explain the findings.
Dr Griffiths commented: "Although the prevalence of obesity is higher than desirable across the whole city, it appears that children living in the most deprived and most affluent areas of the city are at the lowest risk, with boys and girls following different patterns. These results could help make informed decisions at the local level including the allocation of health promotion resources. This is especially important now in the light of the recently enhanced role for local governments and authorities with an increased focus on locally-led action in the UK to tackle childhood obesity."
The study was part of a collaboration between Leeds Metropolitan University, Leeds City Council and the Education Authority.
* A major limitation of the current evidence base to date is that it relies heavily on individual measures of deprivation and comparatively few studies use an area level measure of deprivation, especially applying to children, thereby limiting the scope to assess trends in the association with obesity for this indicator. Research suggests that area level deprivation is associated with obesity independently of individual deprivation (Marmot et al 2010: Stafford et al 2010)
** Explanations for the non-linear association (i.e. not a straight line) between obesity and area level deprivation are not currently understood. It is possible that the linear associations (i.e. a straight line) reported in the literature are a result of the statistical techniques applied. A linear trend was observed (for all measures of adiposity) in the analyses of the RADS data (only significant in girls) when the relationship was assumed to be linear. However, the inclusion of Quadratic terms (e.g. IDACI2 - to allow for curvature in a relationship) was a better representation of the data than using a linear relationship. Without the inclusion of the quadratic term and just relying on the assumption of linear relationships the RADS data would have been in agreement with the existing evidence base.
Marmot, M., Allen, J., Goldblatt, P., Boyce, T., McNeish, D., Grady, M. & Geddes, L. (2010) Fair Society, healthy Lives: Strategic Review of Health and Inequalities in England post-2010, The Marmot Review. University College London.
Stafford, M., Brunner, E. J., Head, J. & Ross, N. A. (2010) Deprivation and the development of obesity a multilevel, longitudinal study in England. American Journal of Preventative Medicine 39, 130-139.