Official Statistics

Obesity Profile: statistical commentary, November 2024

Published 5 November 2024

Applies to England

This commentary relates to data from the National Child Measurement Programme (NCMP) for the academic year 2023 to 2024, focusing on the trends and inequalities in child obesity and child height.

What’s new

The Obesity Profile has been updated with data from the 2023 to 2024 NCMP. The profile displays prevalence of obesity, severe obesity, overweight, healthy weight and underweight at local authority, regional and national level over time, for children in reception (aged 4 to 5 years) and year 6 (aged 10 to 11 years). Inequalities in child obesity prevalence by sex, deprivation and ethnic group for England, regions and local authorities are also displayed. Indicators on the prevalence of overweight and obesity in reception and year 6 show data at a neighbourhood level for middle super output areas (MSOA) and electoral wards.

NCMP data quality indicators have been updated with this latest year of data, such as participation rates and proportions of records with valid child postcode and ethnicity. A full list of all indicators that have been updated is included in the ‘Further information’ section below.

Slide sets showing data on the patterns and trends in child obesity

The national, regional and local authority patterns and trends in child obesity data slide sets have been updated with 2023 to 2024 NCMP data and are available in the ‘Reports’ data view of the Obesity Profile.

The national slide set now includes:

• new charts on the patterns of obesity prevalence by deprivation for ethnic groups
• new charts on trends in obesity prevalence by ethnic group and by region
• a new section showing trends in the height of children in England at age 5 and age 11

A description of the height data is included in the ‘Main findings’ of this statistical commentary below. The charts showing Health Survey for England data have been updated to include the 2022 data that was published in September 2024.

Slide set showing data on the patterns and trends in adult obesity in England

The national slide set on the patterns and trends in adult obesity has been updated with the 2022 Health Survey for England data and is available in the ‘Reports’ data view of the Obesity Profile.

Introduction

The November 2024 update of the Obesity Profile presents the 2023 to 2024 academic year NCMP data for all current indicators. Headline findings from this data are being published by NHS England on the same day, 5 November 2024, in its NCMP 2023 to 2024 school year report.

The NCMP is an annual programme that measures the height and weight of over one million children in reception (age 4 to 5 years) and year 6 (age 10 to 11 years) in primary schools across England. The data is used at a national and local level to monitor the patterns and trends in child weight status, providing valuable evidence for planning and delivering policy measures and interventions.

In the academic year 2023 to 2024, 93.6% of eligible children participated in the NCMP. This is slightly higher than the participation rate in 2022 to 2023 (93.2%), but still lower than 2018 to 2019 (94.9%), before the COVID-19 pandemic.

Main findings

Assessment of the overall trend in child obesity prevalence in England

In 2023 to 2024:

• obesity prevalence for reception children was 9.6%, which was an increase from 9.2% in 2022 to 2023
• obesity prevalence for year 6 children was 22.1%, which was a further decrease from previous years (22.7% in 2022 to 2023)

Projections of obesity prevalence for reception and year 6 have been produced based on pre-COVID-19 data from 2006 to 2007 through to 2019 to 2020.  This allows a comparison between the latest estimates of obesity prevalence with the pre-pandemic trend projected forward.

The projection is presented with 95% confidence intervals - this is a range of values that is used to quantify the uncertainty in the projection. The observed prevalence estimates also have a small level of uncertainty even though nearly all children are measured each year. This primarily reflects the natural variation that would occur if the measurements were taken on a different day.

The data used to produce the charts can be downloaded as an accessible spreadsheet at ‘Obesity Profile: supporting data, November 2024’. This spreadsheet also contains the methods used to produce the projections.

In 2023 to 2024, the observed obesity prevalence for reception children remained in line with pre-pandemic levels, which gave a stable projection (as shown in Figure 1 below).

Figure 1: observed prevalence of obesity among reception children (age 4 to 5 years) for academic years ending 2007 to 2024, compared with projected prevalence for 2020 to 2021 through to 2023 to 2024

Data source: National Child Measurement Programme.

Note on Figure 1: projections, with 95% confidence intervals, are based on data from 2006 to 2007 through to 2019 to 2020.

For year 6 children, following the large increase in 2020 to 2021, obesity prevalence had remained above the projection in 2021 to 2022 and 2022 to 2023, despite these years showing a decrease from the peak observed in 2020 to 2021.

In 2023 to 2024, the year 6 prevalence was, for the first time, in line with the projection based on the pre-pandemic increasing trend (as shown in Figure 2 below).

Figure 2: observed prevalence of obesity among year 6 children (age 10 to 11 years) for academic years ending 2010 to 2024, compared with projected prevalence for 2020 to 2021 through to 2023 to 2024

Data source: National Child Measurement Programme.

Note on Figure 2: projections, with 95% confidence intervals, are based on data from 2009 to 2010 through to 2019 to 2020. Comparisons are not possible with the first years of the NCMP (2006 to 2007 through to 2008 to 2009) as low participation levels led to underestimation of obesity prevalence.

Trends in inequalities in child obesity

Data on inequalities by level of deprivation, ethnicity and geographic area can be viewed in the obesity slide sets and in the Obesity Profile on Fingertips.

Inequalities in obesity prevalence

Deprivation

Persistent inequalities exist in child obesity with children from the most deprived areas of England being twice as likely to be living with obesity compared with those from the least deprived areas.

In 2023 to 2024, 12.9% of children in reception from the most deprived areas were living with obesity compared with 6.0% of children in the least deprived areas. This is an inequalities gap of 6.9 percentage points (pp), which is lower than the year immediately preceding the pandemic (7.3pp in 2019 to 2020) but still larger than 2007 to 2008 (5.1pp) (see Figure 3 below).

Figure 3: inequalities gap in obesity prevalence among reception (age 4 to 5 years) children for academic years ending 2008 to 2024, based on area of child residence

Data source: National Child Measurement Programme.

For children in year 6, 29.2% of children from the most deprived areas were living with obesity compared with 13.0% of children in the least deprived areas. The gap in obesity prevalence between the most and least deprived areas in 2023 to 2024 has reduced compared with 2020 to 2021 (from 19.5pp to 16.1pp) - however, it is still larger than the year immediately preceding the pandemic (15.5pp in 2019 to 2020) (as shown in Figure 4 below).

Figure 4: inequalities gap in obesity prevalence among year 6 (age 10 to 11 years) children for academic years ending 2008 to 2024, based on area of child residence.

Data source: National Child Measurement Programme.

Ethnic group

There continues to be considerable variation in obesity prevalence across ethnic groups. Obesity prevalence in reception children is highest among children from black African (14.2%) and black other ethnic groups (13.2%). Children in year 6 from most ethnic groups (with the exception of white Irish, mixed white and Asian, and Chinese) are more likely to be living with obesity than white British children (20.5%). See slide 39 in the child obesity slide set for England.

Prevalence of obesity among reception children has increased among white British children between 2009 to 2010 and 2023 to 2024, but decreased among children from the following ethnic groups: Indian, Bangladeshi, Asian other, Chinese, black African, other white, and any other ethnic group. See slide 41 in the child obesity slide set for England.

Among children in year 6, prevalence of obesity has increased between 2009 to 2010 and 2023 to 2024 across all ethnic groups with the exception of Chinese and white Irish children where no significant trend was detected. Since 2020, obesity prevalence among Chinese children has decreased and is now at the lowest level recorded by the NCMP since 2010 to 2011. See slide 42 in the child obesity slide set for England.

Deprivation and ethnic group

The pattern of obesity prevalence by deprivation decile varies by ethnic group. Most ethnic groups follow a similar pattern to England with a large gap in prevalence between the least and most deprived areas. However, this pattern is not evident in all groups - reception-aged children of black African and Bangladeshi ethnicity living in the least deprived areas have a similar prevalence of obesity to those in the most deprived areas of England (as shown in Figure 5 below).  

Some ethnic groups have small counts of children measured when split by deprivation decile so their estimates will be less robust than those for the larger groups. The data used to produce the charts can be downloaded as an accessible spreadsheet in ‘Obesity Profile: supporting data, November 2024’. This spreadsheet contains the counts and associated confidence intervals.

Figure 5: inequalities gap in obesity prevalence by ethnic group among children in reception (age 4 to 5 years) academic years ending 2022, 2023 and 2024 combined

Data source: National Child Measurement Programme.

For children in year 6, again most ethnic groups follow a similar pattern to England of prevalence being double in the most deprived areas compared with the least deprived. However, the gap is smaller for year 6 children from black African and black other ethnic groups (as shown in Figure 6 below).

Figure 6: inequalities gap in obesity prevalence by ethnic group among children in year 6 (age 10 to 11 years), academic years ending 2022, 2023 and 2024 combined

Data source: National Child Measurement Programme.

Region

Prevalence of obesity varies across geographic areas in England, with level of deprivation and ethnic mix being contributing factors. In 2023 to 2024, prevalence of obesity among reception children was lowest in the south west (8.8%), south east (8.6%) and east of England (8.4%), and highest in the West Midlands (10.9%), north east (10.8%), Yorkshire and the Humber (10.7%), and north west (10.1%). The overall trend in reception year obesity prevalence for England since 2009 to 2010 is stable. However, obesity prevalence in the north east, north west, and Yorkshire and the Humber has seen a small increase, whereas a small decrease is observed in London.

Among year 6 children in 2023 to 2024, prevalence of obesity was lowest in the east of England (20.0%), south east (19.2%), and south west (19.1%), and highest in the north east (24.5%), West Midlands (24.4%), London (24.0%), Yorkshire and the Humber (23.6%), and north west (23.3%). Prevalence of obesity among year 6 children in England and across all regions has increased since 2009 to 2010.

There is also considerable variation in the prevalence of obesity among local authorities within regions; trends for all lower and upper-tier local authorities can be examined in the regional and local authority obesity slide sets and in the Obesity Profile on Fingertips.

Trend in the height of children aged 5 and 11 years in England

Data on average (mean) height of children aged 5 and 11 years has been added to the child obesity slide set for England.

As children are growing all the time, it is important to ensure that any changes in average height are not due to children being measured earlier or later in the academic year. Therefore, the height estimates have been standardised to be the height of a child aged exactly 5 years and 0 days for reception year and exactly 11 years and 0 days for year 6. The data used to produce the charts can be downloaded as an accessible spreadsheet in ‘Obesity Profile: supporting data, November 2024’. This spreadsheet also contains the methods used to produce the projections.

Children aged 5

The average height of 5-year-old boys and girls in England had been increasing slightly over the period of NCMP data collection up to 2019 to 2020. There was a relatively large increase in average height in 2020 to 2021, which coincided with the large increase in the prevalence of obesity during the pandemic. Since 2020 to 2021, average height has decreased and is now similar to 2018 to 2019 (as shown in Figure 7 below).

Evidence from research literature shows that obesity is associated with accelerated height gain in childhood and timing of puberty, but then a ‘catch-down’ of reduced height gain in adolescence. This is evidenced in references ^{[footnote 1]}, ^{[footnote 2]}, ^{[footnote 3]} and ^{[footnote 4]}.

Figure 7: trend in average (mean) height in centimetres at age 5 in England for academic years ending 2009 to 2024

Data source: National Child Measurement Programme.

Note on Figure 7: y axis does not start at zero.

Children aged 11

The average height of 11 year olds in England has seen small increases over the period of NCMP data collection from academic years ending 2009 to 2020. There was a relatively large increase in average height in 2020 to 2021, which coincided with a large increase in the prevalence of obesity during the pandemic. Since 2021 to 2022, average height of girls has decreased but remains above pre-pandemic levels. Average height of boys has remained above pre-pandemic levels and has not decreased since the pandemic (as shown in Figure 8 below).

Figure 8: trend in average (mean) height in centimetres at age 11 in England for academic years ending 2009 to 2024

Data source: National Child Measurement Programme.

Note on Figure 8: y axis does not start at zero.

Data on mean height of children from the NCMP will be added to the Obesity Profile in February 2025.

Further information

Child body mass index classification

For population-monitoring purposes, a child’s body mass index (BMI) is classed as overweight or obese where it is on or above the 85th centile or 95th centile, respectively, based on the British 1990 (UK90) growth reference data. The population monitoring cut-offs for overweight and obesity are lower than the clinical cut-offs (91st and 98th centiles for overweight and obesity) used to assess individual children - this is to capture children in the population in the clinical overweight or obesity BMI categories and those who are at high risk of moving into the clinical overweight or clinical obesity categories. This helps ensure that adequate services are planned and delivered for the whole population.

List of prevalence indicators using one year of data

The following indicators have been updated with 2023 to 2024 NCMP data for national, regional, upper and lower-tier local authority and integrated care board (ICB) geographies:

• reception and year 6: prevalence of underweight
• reception and year 6: prevalence of healthy weight
• reception and year 6: prevalence of overweight (including obesity)
• reception and year 6: prevalence of overweight
• reception and year 6: prevalence of obesity (including severe obesity)
• reception and year 6: prevalence of severe obesity
• reception and year 6: prevalence of obesity (including severe obesity), 5 years of data combined

List of data quality indicators using one year of data

In the NCMP since 2008 to 2009, over 99% of child records have a valid postcode, providing large enough coverage to produce reliable estimates at small area level. The following indicators have been updated with 2023 to 2024 NCMP data for national, regional, upper and lower-tier local authority geographies:

• participation rate, total
• participation rate, reception
• participation rate, year 6
• records with valid ethnicity code
• records with valid child postcode
• records with height rounded to the whole or half number (X.0 or X.5)
• records with weight rounded to the whole or half number (X.0 or X.5)

List of prevalence indicators using 3 or 5 years of data combined

The following indicators have been updated with local authority-level inequalities data:

• reception prevalence of obesity (including severe obesity), 5 years of data combined
• year 6 prevalence of obesity (including severe obesity), 5 years of data combined

Local authority-level inequalities data is presented by combining 5 years of data. Prevalence of obesity by sex, ethnic group and deprivation quintile can be examined for upper and lower-tier local authorities in the ‘Inequalities’ data view of the Obesity Profile.

The following indicators have been updated in the ‘NCMP small area data’ topic, showing data for middle super output areas (MSOA) and electoral wards, together with local authority and England figures for comparison:

• reception prevalence of obesity (including severe obesity), 3 years of data combined
• reception prevalence of overweight (including obesity), 3 years of data combined
• year 6 prevalence of obesity (including severe obesity), 3 years of data combined
• year 6 prevalence of overweight (including obesity), 3 years of data combined

The small area data is presented by area of child residence using 3-year combined NCMP data to show small area trends from 2008 to 2009 up to 2023 to 2024. This data will assist planning and delivery of services for children, and the targeting of resources at a local level, to help reduce the prevalence of overweight and obesity.

Previous Obesity Profile statistical commentaries have given guidance on the interpretation of small area data. Detailed metadata for each indicator is available in the ‘Definitions’ data view of the Obesity Profile.

Further information on the NCMP data set and data collection is available in the guidance for analysis and data sharing and operational guidance.

The statistics were produced using the national analysis data set provided to the Office for Health Improvement and Disparities (OHID) by NHS England.

Responsible statistician, product leads: Caroline Hancock, Catherine Bray.

For queries relating to this document, contact: [email protected].

References

1. Kempf E, Vogel M, Vogel T, Kratzsch J, Landgraf K, Kühnapfel A, Gausche R, Gräfe D, Sergeyev E, Pfäffle R, Kiess W, Stanik J and Körner A. ‘Dynamic alterations in linear growth and endocrine parameters in children with obesity and height reference values.’ eClinicalMedicine 2021: volume 23, issue 37, 100977. ↩

2. He Q and Karlberg J. ‘Bmi in childhood and its association with height gain, timing of puberty, and final height.’ Pediatric Research 2001: volume 49, issue 2, pages 244-251. ↩

3. Dunger DB, Ahmed ML and Ong KK. ‘Effects of obesity on growth and puberty.’ Best Practice & Research Clinical Endocrinology & Metabolism 2005: volume 19, issue 3, pages 375-390. ↩

4. Giglione E, Lapolla R, Cianfarani S, Faienza MF, Fintini D, Weber G, Delvecchio M and Valerio G. ‘Linear growth and puberty in childhood obesity: what is new?’ Minerva Pediatrics 2021: volume 73, issue 6, pages 563-571. ↩