January 6, 2016

expert reaction to study investigating Mexico’s sugary drinks tax and changes in sales of taxed beverages

Mexico introduced a tax on sugar-sweetened drinks in early 2014 and its effects are the subject of a paper published in The BMJ, with the authors reporting reductions in purchases of taxed drinks and increases in purchases of taxed drinks.

Prof. Richard Tiffin, Professor of Applied Economics and Director of the Centre for Food Security, University of Reading, said:

“This is an important study because it is one of the most rigorous analyses of the implementation of a sweetened beverage tax anywhere in the world. Its results support studies that have been based on simulation, which essentially suggest that that percentage tax is matched by the percentage change in consumption, with a slightly larger response among the poorest people.

“The problem is that for the policy to be really effective at improving health, a much larger reduction in consumption is needed for some consumers. The tax is too blunt an instrument to achieve this.

“We have a lot of evidence about the overall impacts of taxes, but we now need to turn our attention to the ways in which we can achieve the necessary changes in intake amongst those who have seriously worrying levels of consumption.”

Prof. Tom Sanders, Professor emeritus of Nutrition and Dietetics, King’s College London, said:

“This study shows a fall of 12 ml per head per day following the introduction of a sugar tax in Mexico but a 35 ml fall in the poorest households. This is equivalent to about 1 sugar cube (16 kcal) which is a drop in the caloric ocean. Long-term reductions in total energy in the range of 300-500 kcal/d are probably needed to prevent obesity. Furthermore, the study does not show whether total sugar intake went down, as the consumption of fruit juice (which contains just as much sugar as the taxed drinks) went up so the actual reduction in intake is likely to be less than a sugar cube.

“Mexico is a relatively poor country compared to the UK so the impact of tax is likely to be greater.  In the UK, only 15.7% of the household budget is spent on food in the poorest groups according to the latest Family Food Survey (1) and soft drinks only provided 40 kcal per person per day. Consequently a sugar tax in the UK would be unlikely to have much impact on energy intake.”

(1) FAMILY FOOD 2014 https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/485982/familyfood-2014report-17dec15.pdf

* Prof. Sanders’ comment was amended at his own request to give the fall in consumption of sugar-sweetened drinks following introduction of a sugar tax as 12 ml per head per day and 35 ml per head per day fall in the poorest households, rather than 36 ml per head per day as originally stated. (11:20 07/01/2016)

‘Beverage purchases from stores in Mexico under the excise tax on sugar sweetened beverages: observational study’ by M Arantxa Colchero et al. will be published in the BMJ on Wednesday 6 January 2016. 

Declared interests

Prof. Richard Tiffin: “I am Science Director of Agrimetrics, a government-funded data centre that works with businesses across the food system. I have been involved for many years in UK research council and industry-funded studies into the effects of taxation on patterns of consumption, including one study that was funded by a soft drinks manufacturers’ association.”

Prof. Tom Sanders is a Scientific Governor of the charity British Nutrition Foundation, member of the scientific advisory committee of the Natural Hydration Council (which promotes the drinking of water), and honorary Nutritional Director of the charity HEART UK. Prof. Tom Sanders is now emeritus but when he was doing research at King’s College London, the following applied: Tom does not hold any grants or have any consultancies with companies involved in the production or marketing of sugar-sweetened drinks. In reference to previous funding to Tom’s institution: £4.5 million was donated to King’s College London by Tate & Lyle in 2006; this funding finished in 2011. This money was given to the College and was in recognition of the discovery of the artificial sweetener sucralose by Prof. Hough at the Queen Elizabeth College (QEC), which merged with King’s College London. The Tate & Lyle grant paid for the Clinical Research Centre at St Thomas’ that is run by the Guy’s & St Thomas’ Trust, it was not used to fund research on sugar. Tate & Lyle sold their sugar interests to American Sugar so the brand Tate & Lyle still exists but it is no longer linked to the company Tate & Lyle PLC, which gave the money to King’s College London in 2006. Tom also used to work for Ajinomoto on aspartame about 8 years ago.  Tom was a member of the FAO/WHO Joint Expert Committee that recommended that trans fatty acids be removed from the human food chain. Tom has previously acted as a member of the Global Dairy Platform Scientific Advisory Panel and Tom is a member of the Programme Advisory Committee of the Malaysian Palm Oil Board. In the past Tom has acted as a consultant to Archer Daniel Midland Company and received honoraria for meetings sponsored by Unilever PLC. Tom’s research on fats was funded by Public Health England/Food Standards Agency.