The most reliable source of data on child obesity is the National Child Measurement Programme (NCMP), participation in which is compulsory in state-maintained schools. The NCMP measures children at age 4-5 (Reception Year) and age 10-11 (Year 6). For more detail, see Section 3.7.
Due to there being only one state-maintained primary school in the City of London, National Child Measurement Programme (NCMP) data for Hackney and the City of London have been combined to maintain school anonymity, while ensuring that all data are represented. These NCMP data are based on all children who attend state-maintained schools within Hackney and the City of London, regardless of the borough in which they reside.
In Reception Year (age 4-5), almost three quarters (73%) of pupils were a healthy weight in 2014/15, one quarter (26%) were overweight or obese and a tiny proportion (around 1%) were underweight (Figure 1). However, in Year 6 (age 10-11) only 57% of children were a healthy weight, while the proportion who were obese was more than double that in Reception Year pupils (26% and 12%, respectively).
Figure 1: NCMP weight categories in Hackney and the City (2014/15)
There is a very high rate of participation in the NCMP among pupils of mandated schools in Hackney and the City (between 96% and 98% in the seven years over which data is available). However, Hackney and the City have a higher proportion of five and 10-year-old pupils being educated in independent schools (24.5%) than London (10.1%) or nationally (5.7%) and these schools are not required to participate in NCMP.  In particular, almost a quarter (22%) of local 5-19 year olds belong to the Stamford Hill Orthodox Jewish (‘Charedi’) community, the majority of whom are educated in independent Charedi schools. Therefore, despite high participation in mandated schools, local NCMP data represent a lower proportion of the children of Hackney and the City of London than in other boroughs.
In order to address this, a pilot Reception Year health check was performed in 22 of the 23 independent Charedi primary schools in Hackney between January and July 2015. This pilot scheme included height and weight measurement (as collected in the NCMP), hearing and vision checks and a dental assessment. Ninety-five per cent of the 723 children in these schools participated, a participation rate comparable with national participation in the NCMP. The vast majority (around 80%) of the participating children were Hackney residents.
The results of this pilot are presented in Figure 2 for different weight categories, with a higher proportion of children found to be a ‘healthy weight’ than in local state-maintained schools, and a smaller proportion were found to be overweight or obese. Combining these results with the NCMP data for 2014/15 reduces the overall obesity rate in Reception Year children slightly from 12% to 11%, and the proportion overweight from 14% to 13%.
Figure 2: Proportion of Reception Year children in each weight category, 2014/15