Potential impact on prevalence of obesity in the UK of a 20% price increase in high sugar snacks
Taxing selected food and drink products is a familiar approach to tackling diet-related health
problems, but it’s also controversial and hotly debated.
British Prime Minister Boris Johnson recently made a headline-grabbing pledge to review so-
called ‘sin taxes’, and called into question their efficacy, which brought him under heavy fire
from public health leaders and critics in the media.
The term ‘sin tax’ is not a helpful moniker – it suggests that consuming certain products
amounts to a moral failure about which citizens should feel guilty, when in fact the purpose
of such taxes is to make it easier to eat well, to reduce the physiological consequences of
consuming unhealthy food, and to subsidise health care. Obesity and the associated
complications have a substantial impact on individuals’ quality of life and NHS resources. As
such, high sugar drink taxes have been introduced in a number of countries in recent years,
and have been recommended as useful measures by the World Health Organisation (WHO)
for reducing sugar consumption and obesity1 .
Expanding these kinds of taxes beyond sugary drinks to other unhealthy products could
have a significant impact on public health, as detailed in a new paper from SHEFS
researcher Dr Pauline Scheelbeek.
The new study from Dr Scheelbeek (LSHTM), recently published in the BMJ, finds that
increasing the price of high sugar snacks by 20% could reduce energy intake, BMI, and
prevalence of obesity. The paper examines the impact of a 20% price increase for three
categories of high sugar snacks: confectionery, biscuits and cakes.
An earlier observational study conducted by LSHTM in collaboration with the University of
Oxford predicted that adding a 10% cost to biscuits, cake and confectionery could lead to a
7% decrease in purchases2 . The SHEFS study takes this further and provides policy makers
with a sense of the kind of role a tax on high sugar foods could play in tackling obesity and
improving public health.
Health impact of sugar
We know that high sugar consumption means an increased total energy intake and an
increased risk of obesity and diabetes6,7 . We also know that in the UK two in every three
adults are overweight or obese and that obesity is a major risk factor for a number of
conditions including diabetes, heart disease, stroke and several cancers3 . Obesity costs the
NHS £6 billion a year4 and Type 2 diabetes costs a further £14 billion annually5 : a sugar tax
could not only help to reduce and prevent obesity but subsidise the costs it incurs.
This SHEFS study estimates that a 20% price increase on confectionery, biscuits and cakes
would result in a reduction in BMI of 0.53, which could lead to a 2.7% decrease in obesity
prevalence within a year of introducing the tax. Although obesity is a complex, multi-faceted
problem and requires a wide range of strategies to combat it, a 2.7% decrease in obesity is
relatively large compared with other population-level interventions aimed at weight reduction,
and so could be a meaningful way of improving health and reducing obesity related
complications. The potential for the greatest reduction in sugar consumption was seen in
households classified as obese and on a low income, indicating that a sugar tax could help
tackle health inequalities.
Soft drinks industry levy
Although previous taxation strategies to reduce sugar have focused on sugar-sweetened
beverages (SSBs), intake of free sugars in the UK is much greater from high sugar snacks
than SSBs, with biscuits, confectionery and cake contributing 18% of children’s total sugar
intake compared with 9% from soft drinks8 . The soft drinks industry levy (SDIL) (introduced
in the UK in April 2018) taxes drinks with high sugar content, and an evaluation of its impact
is currently underway9 . A systematic review found that a 10% tax on soft drinks results in a
10% decrease in purchases10 . The findings in Dr Scheelbeek’s study are on average double
that which were modelled for a similar price increase in SSBs, indicating that this could
potentially have even more impact on population health than the SDIL.
Voluntary sugar reduction and reformulation programme
The soft drinks industry made significant efforts to reformulate their products once the SDIL
was introduced, and it was hoped that the subsequent voluntary sugar reduction and
reformulation programme for high sugar foods rolled out by PHE in 2017 would lead to
similar changes, encouraging industry to reduce the amount of sugar in the foods that
contribute most to children’s intakes by 20% by 2020, with a 5% reduction in the first year.
The initial focus was on nine food categories which include biscuits, cakes and
confectionery. Projections suggested that if the reduction of 20% by 2020 was met, it could
reduce obesity rates by 5.5% in younger children (<11) and adults and 2.2% in older children
(11-18). Overall, it looked as though the reduction could help prevent 150,000 cases of Type
2 diabetes over 10 years11 .
However, results from the first year were below targets: only an overall reduction of 2% in
calories and sugar content of foods consumed on a single occasion was seen. Sugar
content of biscuits and confectionery were unchanged12 . Results from the second year are
due to be published later this summer, but a lack of satisfying results seen from the voluntary
initiative indicates a need for a binding government intervention similar to the SDIL on these
Sugar taxes in other countries
While there aren’t any examples of taxes specifically on high sugar foods as modelled in this
study, some countries have introduced taxes on ‘unhealthy foods’, which encompass high
sugar products. Mexico implemented an 8% tax on ‘non-essential’ energy dense products
with more than 275kcal per 100g. After two years, this saw a reduction in purchases of these
foods by 7.4% compared with the quantities that would have been purchased should the tax
have not been introduced13 . Similarly, Hungary introduced a 4% tax on packaged foods high
in salt and sugar in 2011. The WHO found that this has led to a decrease in consumption by
not only creating a price barrier but also by changing citizen attitudes and driving behaviour
Conclusion – policy implications
The success of the SDIL and taxes in other countries indicates that a tax on high sugar
foods could have a positive impact on the significant health problems related to sugar. The
results from Dr Scheelbeek’s study take this a step further, demonstrating that a tax on
confectionery, biscuits and cakes could be an effective part of a public health strategy and
make a meaningful difference to the obesity epidemic. Foods that are high in sugar are often
less expensive than healthier alternatives and more likely to be on promotion 15 . We need to
shift the balance so that healthier foods are more affordable than their less healthy
counterparts. And if a sugar tax was introduced on certain foods, the revenue could be used toincrease access to healthy foods for people on a low income, so that the tax also helps to tackle health inequalities.
Last year, Action on Sugar called for the introduction of energy density levy on confectionery
at a minimum of 20%16 . A YouGov poll found a 55% approval rating for taxes on unhealthy
food and drink17 , highlighting a public desire for change. This SHEFS paper illustrates for
policy makers that introducing a 20% tax on certain high sugar foods deserves serious
consideration and could play a key role in tackling diet-related illness.
1. Taxes on Sugary Drinks: Why Do It? https://apps.who.int/iris/bitstream/handle/10665/260253/WHO-NMH-PND-
16.5Rev.1-eng.pdf;sequence=1. Accessed September 3, 2019.
2. Smith RD, Cornelsen L, Quirmbach D, Jebb SA, Marteau TM. Are sweet snacks more sensitive to price increases than sugar-sweetened beverages: analysis of British food purchase data. BMJ Open. 2018;8:19788. doi:10.1136/bmjopen-2017-019788
3. NHS Digital. Statistics on Obesity, Physical Activity and Diet – NHS Digital. https://digital.nhs.uk/data-and-
information/publications/statistical/statistics-on-obesity-physical-activity-and-diet. Accessed August 29, 2019.
4. McKinsey Global Institute. Overcoming Obesity: An Initial Economic Analysis.; 2014.
5. Diabetes.co.uk. Cost of Diabetes. https://www.diabetes.co.uk/cost-of-diabetes.html. Accessed August 29, 2019.
6. Malik VS, Willett WC, Hu FB. Global obesity: trends, risk factors and policy implications. Nat Rev Endocrinol.
7. WHO. Reducing free sugars intake in adults to reduce the risk of noncommunicable diseases. WHO. 2019.
8. Public Health England. Sugar Reduction: Achieving the 20%.; 2017. www.facebook.com/PublicHealthEngland.
Accessed August 29, 2019.
9. CEDAR. Soft Drinks Industry Levy Evaluation – The Centre for Diet and Activity Research.
https://www.cedar.iph.cam.ac.uk/research/dietary-public-health/food-systems-public-health/sdil/. Accessed September 2, 2019.
10. Teng AM, Jones AC, Mizdrak A, Signal L, Genç M, Wilson N. Impact of sugar-sweetened beverage taxes on
purchases and dietary intake: Systematic review and meta-analysis. Obes Rev. 2019;(January):1187-1204.
11. Amies-Cull B, Briggs ADM, Scarborough P. Estimating the potential impact of the UK government’s sugar reduction programme on child and adult health: modelling study. BMJ. 2019;365:l1417. doi:10.1136/bmj.l1417
12. Public Health England. Sugar Reduction and Wider Reformulation Programme: Report on Progress towards the First 5% Reduction and next Steps.; 2018.
13. Taillie LS, Rivera JA, Popkin BM, Batis C. Do high vs. low purchasers respond differently to a nonessential energy-
dense food tax? Two-year evaluation of Mexico’s 8% nonessential food tax. Prev Med (Baltim). 2017;105:S37-S42.
14. World Health Organisation. The Public Health Product Tax in Hungary Good Practice Brief. http://www. Accessed
August 29, 2019.
15. The Food Foundation. The Broken Plate.; 2019.
16. Action on Sugar. The Conversation Continues… Call for Theresa May to Introduce an Energy Density Levy on
Confectionery, Make Nutritional Labelling on Menus &amp; Packaging Mandatory and Ban Marketing of HFSS
Products. http://www.actiononsugar.org/news-centre/press-releases/2018/the-conversation-continues-call-for-theresa-may-to-introduce-an-energy-density-levy-on-confectionery-make-nutritional-labelling-on-menus–packaging-mandatory-and-ban-marketing-of-hfss-products.h. Published 2018. Accessed August 29, 2019.
17. Adam Briggs. Revealed: The evidence which shows we need the sugar tax to fight the obesity epidemic. Telegr.
https://www.telegraph.co.uk/global-health/climate-and-people/revealed-evidence-shows-need-sugar-tax-fight-obesity-epidemic/. Accessed August 29, 2019.