The NIHR has funded research into approaches to prevent obesity in children in a range of community settings (e.g., the home, childcare and pre-school). It has explored the impact of local authority spending on prevention. Research into the impact of other areas on children (e.g. school-based interventions, the food environment, active travel, weight management programmes for children living with obesity) are included in the relevant sections of this review.

What’s the context?

• Childhood obesity is increasing across the UK. Obesity rates in schoolchildren aged 4 to 5 and 10 to 11 years increased by around 4.5% per year between 2019/20 and 2020/21, in the height of the COVID-19 pandemic and during periods of lockdown. This is the highest annual rise since the National Child Measurement Programme began (NHS Digital).
• Living with obesity or overweight in childhood has profound impacts on health, and doubles the risk of dying prematurely (HM Government). Related physical health issues include type 2 diabetes; mental health problems include depression (Chief Medical Officer).
• Certain groups of children are disproportionately affected, and inequalities are increasing. Children living in the most deprived areas are more than twice as likely to be living with obesity as those living in the least deprived areas (NHS Digital). Children from certain minority ethnic groups, or with intellectual and/or physical disabilities are at increased risk (Public Health England).
• The Marmot Review stated that health inequalities result from social inequalities. Every child needs the best start in life. Investment in the early years needs to be increased; families need support to develop their children’s skills.
• The factors that contribute to childhood obesity are complex and multifactorial. Structural actions that go beyond education and information are needed. This can include using planning and licensing powers, for example by tightening restrictions on the advertising of unhealthy foods (Public Health England).
• Local authorities can create healthier environments for children, for example planning policies which: limit new fast food outlets close to schools; prioritise active travel; and ensure access to green space to promote physical activity (HM Government), in addition to involvement in the oversight of children’s centres and voucher schemes for low income families.

What does NIHR research tell us?

Improvements in diet and physical activity can prevent obesity, particularly in younger children

Few interventions in the last 25 years have targeted the wider causes (determinants) of childhood obesity (such as infrastructure, environmental and policy factors). They have instead largely focused on encouraging children to change their individual behaviours by eating more healthily and being more active.(1)(NIHR Alert)

Interventions that include diet or physical activity components, or both, have been shown to reduce the risk of obesity in children aged 0 to 12 years, and do not worsen health inequalities. However, most studies have reported at 12 months or earlier, so the long-term effectiveness of these interventions is not known. (2) Support for physical activity alone can prevent obesity in children aged 6 to 12 years.(2) However, there is no evidence to support the use of behavioural interventions on diet alone.(2) Health is not a motivating factor for adolescents aged 13-14; they are unlikely to engage in approaches designed solely to improve health. Approaches that align with their values and priorities – such as being with their friends and doing things they enjoy – are more likely to succeed.(3)

Sure Start children’s centres may help prevent obesity in children

Cuts to spending on Sure Start children’s centres have been linked to increases in obesity. After each 10% spending cut, more children aged 4 to 5 years had obesity the following year (0.34% relative increase in prevalence).(4)

A voucher scheme did not increase purchases of fruits or vegetables

The Healthy Start scheme provides vouchers to low-income families with a child under 4, and pregnant women, to buy basic foods like milk or fruit. The scheme has not been shown to alter fruit or vegetable purchases. This may be because only around half of eligible households participated, or due to the low value of the voucher.(5)

Useful resources

• Public Health England, in partnership with the Local Government Association (LGA) and the Association of Directors of Public Health (ADPH), has created a resource to help local authorities support children, young people and families to maintain a healthy weight. It includes briefings for elected members, local authority corporate leadership teams, children’s services, and highways, housing, leisure, sport and culture, planning, procurement, and parks and green spaces departments.
• The National Children’s Bureau has identified approaches to reduce obesity involving the voluntary, community and social enterprise (VCSE) sector, education and local government.

NIHR research in progress

• What interventions work best for preventing obesity in children, which groups of children are they effective for (e.g., ethnic and socioeconomic backgrounds), and how much do they cost?(6)
• How effective are approaches to improve parental understanding of childhood overweight and obesity;(7) and those to implement a programme for parents aimed at preventing obesity in preschool children?(8)

1. Nobles J, Summerbell C, Brown T, Jago R, Moore T. A secondary analysis of the childhood obesity prevention Cochrane Review through a wider determinants of health lens: implications for research funders, researchers, policymakers and practitioners. Int J Behav Nutr Phys Act. 2021 Feb 10;18(1):22.
2. Brown T, Moore TH, Hooper L, Gao Y, Zayegh A, Ijaz S, et al. Interventions for preventing obesity in children. Cochrane Database Syst Rev. 2019;(7).
3. Strömmer S, Shaw S, Jenner S, Vogel C, Lawrence W, Woods-Townsend K, et al. How do we harness adolescent values in designing health behaviour change interventions? A qualitative study. Br J Health Psychol. 2021;26(4):1176–93.
4. Mason KE, Alexiou A, Bennett DL, Summerbell C, Barr B, Taylor-Robinson D. Impact of cuts to local government spending on Sure Start children’s centres on childhood obesity in England: a longitudinal ecological study. J Epidemiol Community Health. 2021 Sep 1;75(9):860–6.
5. Parnham J, Millett C, Chang K, Laverty AA, von Hinke S, Pearson-Stuttard J, et al. Is the healthy start scheme associated with increased food expenditure in low-income families with young children in the United Kingdom? BMC Public Health. 2021 Dec 17;21(1):2220.
6. Higgins JPT. Towards optimal public health interventions for preventing obesity in children: a novel evidence synthesis NIHR131572. NIHR Funding and Awards Search Website. [cited 2022 Feb 4].
7. Adamson A. Can embedding the MapMe intervention, a tool to improve parental acknowledgement and understanding of childhood overweight and obesity, in the National Child Measurement Programme lead to improved child weight outcomes at one year? NIHR127745. NIHR Funding and Awards Search Website. [cited 2022 Feb 4].
8. Bryant M. Implementation optimisation and pilot cluster randomised controlled trial of HENRY, a community based programme aimed at preventing obesity in pre-school children. NIHR Funding and Awards Search Website. [cited 2022 Feb 28].