Scientific Article
Evidence is Sweet

Fiona Godlee (E-mail:
Godlee Fiona. Evidence is sweet BMJ 2019; 366 :l4617
  • Source
    British Medical Journal
  • Release date

Evidence is Sweet

Research Editorial


The man most likely to be the UK’s next prime minister has called for a review of what he calls “stealth sin taxes”. Boris Johnson says he is concerned about their disproportionate effect on poor people. He also wants to base the UK’s tax policy “on clear evidence.” If so, all of us who want to improve the public’s health can rest easy: the accumulating evidence in favour of such taxes is becoming hard to counter.

First comes the evidence of the damage caused by excessive intake of sugar and of sugary drinks in particular. To the long and evidence based list itemised by Adam Briggs — weight gain and obesity, diabetes, tooth decay, heart disease, and hypertension—we can now add cancer. A French study in over 100 000 people, published this week in The BMJ, finds a positive association between overall risk of cancer and intake of sugary drinks.

What then of the evidence that taxes work to reduce harmful intake? As Adam Briggs writes, the cumulative evidence suggests that a 10% increase in price is broadly associated with a 10% fall in sales. This has been accompanied by a rise in sales of healthy alternatives such as water.

As for the regressive nature of “sin taxes,” Briggs reports that behaviour change and health benefits are both greater among people in lower socioeconomic groups. Briggs suggests that, rather than dismantling an effective regressive tax, we should be finding ways to improve other progressive taxes.

But Johnson is an ideologically driven politician for whom the evidence is unlikely to hold much sway. More persuasive may be the growing public support for taxing unhealthy foods and drinks—55% at the last count, reports Briggs, including 54% of Conservative voters.

Source Website: The British Medical Journal