Urgent action is needed to reduce widening inequalities in childhood obesity

Adam Briggs is an Associate Clinical Professor and Honorary Consultant in Public Health at the University of Warwick. Mohammed Hudda is an applied medical statistician at St George’s, University of London, with expertise within the field of childhood obesity assessment, particularly in relation to ethnic inequalities. Harry Rutter is Professor of Global Public Health at the University of Bath. 

A recent Public Health England (PHE) report on childhood obesity trends in England up to the 2018-2019 academic year makes for uncomfortable reading. [1] The report draws on data from the annual National Child Measurement Programme (NCMP) which started in 2006-07. The NCMP measures the height and weight of 4-5 year-olds (Reception school year) and 10-11 year-olds (school Year 6) across England, providing data on the prevalence of overweight and obesity in over a million children every year. [2] The report highlights that the proportion of children with overweight or obesity remains extremely high, and is increasing over time in most groups. [1] Furthermore, these increases disproportionately affect children from deprived areas, and those of Black or South Asian ethnicity.

Inequalities in obesity prevalence by deprivation are widening in all age and sex groups. For example, between 2009-10 and 2018-19, the percentage of Year 6 boys with obesity from the most deprived quintile has risen from 25% to nearly 30%, double the prevalence within the least deprived quintile where obesity rates have slightly declined to just below 15%. The same pattern is seen among Year 6 girls, with obesity rates rising from around 22% to 24% in the most deprived quintile compared with a slight fall to 11% in the least deprived.

Data by ethnicity show that while inequalities in obesity prevalence between White British children and Asian and Black children have narrowed among 4-5 year olds (particularly for boys), they have widened dramatically among 10-11 year olds. The prevalence of obesity among White British girls and boys in Year 6 has remained relatively static since 2009-10 at around 16% and 20% respectively, compared with significant reported rises among South Asian and Black children. [1]

However, recent work has demonstrated that body mass index (BMI) underestimates adiposity among South Asian children and overestimates it among Black children. [3,4] Therefore, by choosing to publish BMI unadjusted for ethnicity, the NCMP reported prevalence of obesity among Indian (~26%), Pakistani (~30%), and Bangladeshi (~35%) boys is, in fact, an underestimate. Likewise, the percentages of Year 6 Black Caribbean (~27%) and African (~29%) boys with obesity are overestimates. Were the NCMP to move to reporting obesity prevalence and trends using adjusted BMI, a more accurate picture of the obesity burden within these groups would be obtained, and more appropriate policies could be developed to support Black and Asian ethnic groups.

In any context these data would be important, but the inequalities by ethnicity and deprivation seen in these obesity figures echo those seen in covid-19 among adults, and serve to amplify the need for urgent action. Age-standardised death rates from covid-19 are over twice as high among the most deprived 20% of the country compared to the least deprived. Covid-19 death rates are four times higher among Black males and 2.5 times higher among Asian males, compared with White males, likely driven by deprivation and higher viral exposure of people in these ethnic groups. Furthermore, growing evidence suggests that obesity is itself an independent risk factor for both being diagnosed with covid-19, and for more severe outcomes. [5]

Although NCMP data relate to childhood, they reveal patterns of inequality seen throughout the lifecourse which need to be addressed early in life as part of an effective obesity prevention and management strategy. Obesity is the end result of complex interactions between multiple environmental, economic, commercial, and social factors leading to physical inactivity and unhealthy diets. [6] Responding to obesity requires a multifaceted approach—no single policy will reverse rising trends or widening inequalities. [7]

Any obesity strategy must place tackling the root societal drivers of poor health and wellbeing at its centre, taking a cross-government and cross-sectoral approach to health inequalities. The current covid-19 pandemic has thrown these inequalities into even starker relief, and creates an overwhelming imperative to re-evaluate how we, as a society, view inequalities and the shameful fact that some people are less healthy than others because of their backgrounds. [8]

A second key part must directly target the environmental drivers of obesity. Population level policies such as increasing advertising restrictions on unhealthy food, introducing calorie labelling in bars and restaurants, and expanding opportunities for active travel can not only improve health, but help to narrow inequalities. [9] Chapters Two and Three of the Childhood Obesity Plan reference a range of these population-level policies, some of which were proposed as far back as 2018, but with consultation responses still unpublished. [10] Along with shifting to the NCMP reporting BMI adjusted for ethnicity, much of this can be enacted now.

Covid-19 and its consequences are having a devastating effect on inequalities. It disproportionately affects people who are poor, from Black, Asian and minority ethnic groups, the elderly, those with obesity, and people working in low paid and manual jobs. [5]

The prime minister has talked of the need for “‘levelling up” society to reduce inequalities, and his intention to be “more interventionist” on obesity. [11] The government has already proposed a number of sensible population-level policies, and while they are far from sufficient to solve the problem of obesity on their own, they constitute important steps towards tackling this key national priority. [12] The sooner they are put in place the better.

This blog was originally posted via BMJ Opinion on 13 July 2020.

All articles posted on this blog give the views of the author(s), and not the position of the IPR, nor of the University of Bath.

Are you a decision-maker in government, industry or the third sector? Apply now to our virtual Policy Fellowship Programme for access to University of Bath research and expertise. Learn more. 

-

References

1. Public Health England. National child measurement programme (NCMP): trends in child BMI. 2020. https://www.gov.uk/government/publications/national-child-measurement-programme-ncmp-trends-in-child-bmi-between-2006-to-2007-and-2018-to-2019/national-child-measurement-programme-ncmp-trends-in-child-bmi (accessed June 10, 2020).
2. NHS Digital. National Child Measurement Programme. 2020. https://digital.nhs.uk/data-and-information/publications/statistical/national-child-measurement-programme (accessed June 20, 2020).
3. Hudda MT, Nightingale CM, Donin AS, et al. Reassessing Ethnic Differences in Mean BMI and Changes Between 2007 and 2013 in English Children. Obesity 2018; 26: 412–9.
4. Hudda MT, Nightingale CM, Donin AS, et al. Body mass index adjustments to increase the validity of body fatness assessment in UK Black African and South Asian children. Int J Obes 2017; 41: 1048–55.
5. Public Health England. COVID-19: review of disparities in risks and outcomes. London, 2020 https://www.gov.uk/government/publications/covid-19-review-of-disparities-in-risks-and-outcomes.
6. Rutter H, Savona N, Glonti K, et al. The need for a complex systems model of evidence for public health. Lancet (London, England) 2017; 390: 2602–4.
7. McPherson K, Marsh T, Brown M. Foresight. Tackling Obesities: Future Choices – Modelling Future Trends in Obesity and the Impact on Health. 2nd Edition. London, 2007.
8. Bibby J, Everest G, Abbs I. Will COVID-19 be a watershed moment for health inequalities? London, 2020.
9. Adams J, Mytton O, White M, Monsivais P. Why Are Some Population Interventions for Diet and Obesity More Equitable and Effective Than Others? The Role of Individual Agency. PLoS Med 2016; 13: e1001990.
10. The Cabinet Office, The Department of Health and Social Care. Advancing our health: prevention in the 2020s. London, 2019.
11. Swinford S. Boris Johnson to launch war on fat after coronavirus scare. The Times. 2020; published online May 15.
12. Davies SC. Time to solve childhood obesity: CMO special report. London, 2019.