Thursday, 2 June 2022

Illiterate 'public health' bozos

The tweet below comes from Wakefield's director of public health who is paid at least £124,000 per annum.

Restricting advertising of unhealthy food and drinks could reduce childhood obesity by two-thirds?! That is, er, quite a claim. Does it sound remotely plausible to you?

However, she cites a source so let's have a look at 'How can local authorities reduce obesity?' by the National Institute for Health Research. It has a section on advertising and it does indeed make that claim. 
Modelling research has predicted that restricting advertising of unhealthy food and drinks between 05:30 and 21:00 could reduce childhood obesity by two-thirds, and help tackle health inequalities.(19)

Reference 19 is this study which modelled the possible effect of a ban on HFSS food advertising before 9pm. It estimated that such a ban could reduce average energy intake by nine calories per day which would somehow reduce childhood obesity by 4.6%.
We estimate that if all HFSS advertising between 05.30 hours and 21.00 hours was withdrawn, UK children (n = 13,729,000), would see on average 1.5 fewer HFSS adverts per day and decrease caloric intake by 9.1 kcal (95% UI 0.5-17.7 kcal), which would reduce the number of children (aged 5-17 years) with obesity by 4.6% (95% UI 1.4%-9.5%) and with overweight (including obesity) by 3.6% (95% UI 1.1%-7.4%).

4.6% is not 67%, so where did the claim about a two-thirds reduction come from? It seems to have come from this line in the study:

Under a scenario where all HFSS advertising is displaced to after 21.00 hours, rather than withdrawn, we estimate that the benefits would be reduced by around two-thirds.

What hope is there for people like Anna Hartley, who is merely a well remunerated foot soldier, when the National Institute for Health Research can't read a simple abstract? 
The actual claim is that there would be a tiny reduction in calorie intake if these adverts were banned, which would be smaller still if the ads were broadcast after 9pm instead (which most of them would be). 
We really are dealing with idiots, aren't we? We have people who can't think taking their lines from people who can't read.

Incidentally, the study itself is garbage and almost certainly overestimates the impact, as I have explained before.

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