The claim that British children are shrinking due to malnutrition/austerity/ultra-processed food/Brexit won't go away. Devi 'zero Covid' Sridhar mentioned it in the Guardian today.
Data shows that children in the UK are becoming shorter compared to other countries, and it’s been asserted that the average height of a five-year-old in the UK is likely to have decreased because of rising child poverty and Conservative austerity policies.
But, as I say in The Critic today...
Devi gets it right the first time when she says kids are “becoming shorter compared to other countries” but gets it wrong the second time when she claims that average height has decreased. The fact is that British children have never been taller. They have grown by about a centimetre on average since 2010.
Let's nail this once and for all. Some media have being saying that the UK has slipped down the rankings when it comes to the height of five year olds (true), but others have claimed that their height has decreased in absolute terms. The Times used the graph below which seems to show a 2mm decline since 2013.
As you can see, the source for these figures is the NCD Risk Factor Collaboration. If you visit their website, their source is this study from the Lancet. And if you look at the appendix of that study, you'll see that its source for the UK figures is the National Child Measurement Study.
It could hardly be anything else. The National Child Measurement Study is the only piece of research that measures the height of the nation's school children.
The figures published by the NCD Risk Factor Collaboration do indeed suggest a slight reduction in height in the last decade or so. The trouble is that the figures from the National Child Measurement Study do not. They are shown below and can be downloaded here.
These figures show that the height of boys and girls stayed much the same between 2009/10 and 2018/19, but has risen in recent years. On average, Reception age kids (aged 4-5) are nearly a centimetre taller than they were in 2012/13.
The figures between 2006/07 and 2008/09 are slightly higher than the figures in the years immediately after, but the researchers say that they "could have been affected by lower participation in the measurement programme." The figures for 2020/21 are unusually high because they were taken later in the school year than usual (and so the kids were bigger). The figures for 2019/20 were also affected by the pandemic and may not be comparable.
Excluding the anomalous year of 2020/21, the most recent years show that English children are, on average, taller than ever. As far as I can see, the figures from the NCD Risk Factor Collaboration are simply wrong. For example, they give a figure of 112.5cm for five year old boys in 2019 which is a couple of centimetres taller than the figure above.
The NCD's figures are for the UK whereas the figures above are for England, but I seriously doubt that this explains the discrepancy. The NCD cites the Scottish Health Survey as an additional source but doesn't cite anything for Wales or Northern Ireland. It is implausible that the addition of Scottish figures could change both the data points and the overall trend so much.
I can't really explain why the NCD/Lancet figures bear so little resemblance to the figures in the source they cite, but they do seem to be wrong.
Don't forget to read my piece in The Critic.
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