Liz Truss should scrap the sugar tax

In public health circles, it is considered terribly gauche to expect policies to work. You might think, for example, that a trailblazing intervention designed to reduce obesity would be considered a failure if obesity rates rise to record highs after it has been implemented. Not so with the sugar tax. Obesity among both children and adults has gone up since it was introduced in 2018, but the health lobby does not consider it to be a failure. Contrary to the evidence of your eyes, they say, it has actually been a success. The only failure is the failure of the government to do lots of other things in addition.

This is one of a number of ways in which ‘public health’ differs from medicine. If a patient’s health gets worse after being given some pills, doctors do not claim that the treatment has been a success and double the dose.

The sugar tax has only been in place for four years and yet the Guardian tells us that civil servants are ‘aghast’ at the possibility that Liz Truss might get rid of it. Everyone from the Institute for Government to the Soil Association is up in arms at the thought of the nanny state juggernaut coming to a halt or even u-turn under Truss’s watch.

And yet the sugar tax hasn’t worked in the UK – neither has it worked in any other country. There is a good deal of economic research showing this and explaining why (in short, people pay up or switch to other sugary products). It is not, and never has been, an evidence-based policy.

It is reasonable to expect the rest of the anti-obesity policies currently under review by the government to be as successful as the other big ticket public health interventions of recent years – plain cigarette packaging and minimum alcohol pricing – i.e. not at all. There is no credible evidence that bans on food advertising, restrictions on where shopkeepers can position their groceries or the prohibition of volume price discounts (such as BOGOFs) will have any impact on obesity.

The advertising ban and the BOGOF ban were postponed by Boris Johnson when inflation started rising and it would be surprising if Liz Truss doesn’t postpone them indefinitely. She hates nothing more than the nanny state and this is an excellent opportunity for her to set out her stall, rile The Blob and show the public that she is on their side.

The ban on retailers positioning ‘less healthy’ food at the entrance, exit and end-of-aisle is due to come into force next month. Supermarkets have been busily rearranging their premises and customers have already started complaining that they can’t find anything. I’m told that the supermarkets are quietly pleased about this as it makes people walk down aisles they would not usually bother with, picking up products as they go (this is why supermarkets hide the eggs in the furthest reaches of the store). They have spent a lot of money complying with the new legislation. Too bad. Let us not fall for the sunk cost fallacy. If Sainsbury’s wants to put nothing but toilet paper and whisky at the end of their aisles (alcohol is exempt from the ban), they are free to do so, but there should no law compelling them.

I could give you philosophical reasons why the government shouldn’t be meddling with the food market in such a way. I could give an explanation rooted in economics to show why such interventions are misguided and counter-productive. But I don’t need to bother. The simple fact is that the policies that have been tried haven’t worked and the policies that are pending are very unlikely to work. That is all the justification Liz Truss needs to get rid of them.