The Times has come out in favour of a sugar tax today. ‘It is time for a sugar tax,’ says an editorial, ‘because nothing else is working.’ One expects a little more intellectual rigour from Britain’s erstwhile newspaper of record. Extracting hundreds of millions of pounds a year from the British public to try something that has failed in every country in which it has been tried demands a better rationale than ‘something must be done — this is something and therefore it must be done’.
Doctors do not resort to treating patients with witchcraft because ‘nothing else is working’. In the age of evidence-based medicine, evidence is required. So too is an assurance that it will do no harm. Taxing food and soft drinks in the name of obesity has been tried in the USA, Finland, Mexico, Hungary, France and Denmark but the effect on sales has been trivial and if there has been any reduction in obesity, it has been far too small to measure. After years of real-world experimentation, the evidence to support a sugar tax remains confined to crude theoretical models which fail to account for how consumers actually behave.
The Danish fat tax was so unpopular that it was repealed after barely a year, partly because it was unambiguously regressive. The Times‘s leader acknowledges that such taxes clobber the poor harder than the rich but diverts attention from this by claiming that ‘If a sugar tax hits the poor hardest, they will see its benefits most clearly too.’ But unlike the cost of the tax — which is real and easy to calculate — the ‘benefits’ remain a figment of the imagination. Even if such blessings exist it is far from certain that they will fall on the poor.
For what it’s worth, the most widely cited modelling exercise, published in the British Medical Journal in 2013, ‘did not find greater health gains for poorer people’. The study’s authors — one of whom literally believes that ‘God is calling me to work towards the introduction of soft-drink taxes in this country’ — noted that people on low incomes are less price sensitive when it comes to sugary drinks and that there will therefore be ‘a smaller response by the lowest income group’.
Overall, the study predicted that a 20 per cent tax on sugary drinks would reduce calorie consumption by four calories a person per day. That is the equivalent of walking up and down a flight of stairs. It amounts to 0.16 per cent of a man’s recommended daily calorie intake. It is the equivalent of one gram of sugar (there are 35 grams in a can of Coke). It is one 20th of a slice of bread.
That is the reduction in energy intake that a highly optimistic model based on a tax rate twice as high as the 10 per cent supported by the Times found. There are, I would suggest, better ways to spend a half a billion pounds.