Introduction

Excessive sugar consumption is continuing to fuel a growing public health crisis in the UK, contributing to rising rates of obesity, type 2 diabetes, cardiovascular disease, and poor oral health.

Research shows that the average five-year-old consumes their own body weight in sugar every year¹, and children’s sugar intake remains around double the recommended maximum dietary amount, placing children at high risk of tooth decay.² Among children aged five to nine in England, tooth decay is the leading cause of hospital admissions³, despite being almost entirely preventable. Sugar’s impact on early-life health is disproportionate, as children’s enamel is thinner and less resistant, and children’s primary (baby) teeth are more susceptible to decay than permanent (adult) teeth, with nearly 1 in 5 five-year-olds (23.7%) having experienced dental decay.⁴ Excessive sugar consumption also contributes to high rates of obesity⁵, 37% of year six children are overweight or living with obesity, and 64% of adults aged 16 years and over were overweight or obese in 2022.⁶ New modelling predicts the proportion of year six students being overweight or living with obesity will rise to 41% by 2034-35.⁷       

What is tooth decay?

Tooth decay, also known as dental caries or cavities, is one of the most common health problems worldwide. It affects people of all ages - from young children to older adults. Tooth decay occurs when the hard outer layer of the tooth, called enamel, is damaged. This damage happens when acid gradually wears it down, creating soft spots or holes that, if untreated, worsen over time.

How sugar causes tooth decay

Sugar is one of the leading causes of tooth decay. When we consume sugary foods or drinks - such as sweets, fizzy drinks, or fruit juice - the bacteria in our mouths feed on the sugar and produce acid as a by-product.

When acid is produced, a "demineralisation window" is initiated, where essential minerals are stripped from the tooth enamel. If sugary drinks and food are consumed multiple times a day, our teeth are under constant acid attack, shortening the time available for mineralisation by saliva. Cumulative acid exposure over time significantly increases the risk of dental caries. 

The Impact of the SDIL

In response to this growing burden, the UK government introduced the Soft Drinks Industry Levy (SDIL)⁸ in 2018 to encourage manufacturers to reformulate products and reduce the availability of high-sugar drinks. The SDIL targets sugar-sweetened beverages (SSBs), which were identified in the 2016 Childhood Obesity Plan⁹ as the largest single source of dietary sugar for children.  Since the introduction of the SDIL, manufacturers have reduced the average sugar content of soft drinks by 46%, and the volume of total sugar purchased in levy-eligible drinks dropped by 39.8%, equivalent to 57,000 tonnes.² 

Evidence shows that fiscal measures like the SDIL are effective tools to create healthier food environments and shift consumer and industry behaviour. The policy has already had a measurable impact on improving health outcomes, including an 8% relative reduction in obesity among girls aged 0-11, approximately 5,234 fewer cases annually.¹⁰ The SDIL is also linked with a 12.1% reduction in hospital admissions for tooth extractions due to dental decay, especially in younger children, across most areas regardless of deprivation. This is based on a model comparing to a scenario in which the policy was not introduced.¹¹ Since the levy was introduced, high-sugar drinks (over 8g sugar/100ml) have dropped from 25.6% to 8.8% of sales, while lower-sugar drinks (under 5g/100ml) have risen from 67% to 90.5%.² So far, the SDIL has successfully reduced sugar through reformulation and a market shift to low-sugar options across demographics.

Consultation on expanding the SDIL

Following a formal review of the SDIL in December 2024, HM Treasury and HM Revenue and Customs launched a consultation in April 2025, proposing enhancements to the SDIL.¹² Key proposals include reducing the minimum sugar content at which the levy applies from 5g to 4g per 100ml and including milk-based drinks and milk substitutes with added sugars under the levy.

The consultation closed on 21 July 2025, with final decisions expected in the Autumn Budget 2025.

FDS position and recommendations

The FDS strongly supports strengthening the SDIL. We believe the levy’s expansion and continued reinvestment in public health is essential to protecting children’s oral health. 

1. Lower the SDIL sugar threshold to 4g per 100ml and extend it to include milk-based sugary drinks to better protect children’s oral health

The SDIL currently applies to drinks containing more than 5g of sugar per 100ml. There is a clear need to include milk-based drinks, given that between 2015 and 2024, volume sales of pre-packed milk-based drinks increased by 53.2%, and pre-packed flavoured milk substitutes drinks rose by 18.7%. Moreover, sugar sold in pre-packed milk-based drinks increased by 30.3%.² 

We support the government’s proposal to: 

• Lower the sugar threshold to 4g per 100ml to encourage further reformulation and reduce consumer sugar intake.
• Remove the exemption for milk-based drinks with added sugars beyond those sugars naturally derived from the principal ingredient, such as oats or rice. 

2. Commit a portion of SDIL revenue to prevention programmes such as supervised toothbrushing programmes and community fluoride varnish schemes, and for access to NHS dental services

The SDIL generated over £338 million in the 2023-2024 financial year.¹³ However, this revenue has not been directed toward oral health, despite dental decay being one of the most common preventable diseases in children. 

We call on the government to:

• Ring-fence a portion of SDIL revenue for prevention programmes, including supervised toothbrushing programmes in all primary schools, free breakfast clubs, and community fluoride varnish schemes.
• Allocate funding specifically for child General Anaesthetic procedures to extract carious teeth, addressing the backlog affecting children and reducing delays for unrelated surgical interventions.
• Prioritise funding for targeted interventions in communities with the highest rates of childhood dental decay, where inequality in oral health outcomes is most pronounced and for children from disadvantaged backgrounds who are more likely to consume products high in fat, sugar and salt (HFSS).

3. Raise public awareness to ensure the public understands the health risks of excessive sugar consumption

High sugar consumption is a common driver behind several interconnected health challenges, which are largely preventable. Evidence shows that population-level interventions, such as the SDIL, are more effective, equitable, and cost-saving in creating behavioural change than relying solely on individual behavioural changes. ¹⁴

The FDS is committed to complementing this work by continuing to raise awareness of the harms associated with excessive sugar consumption. We call on the government to launch a public awareness campaign addressing the risks of excessive sugar consumption.    

In addition to upstream, population-level interventions, the FDS recognises the importance of individual-level, downstream approaches to behaviour change. There is a strong evidence base¹⁵ for supporting people to reduce their sugar intake to below 5% of total energy intake, as recommended in Delivering Better Oral Health: an evidence-based toolkit for prevention.¹⁶ This guidance outlines effective approaches to preventing dental caries, including reducing both the volume and frequency of free sugar consumption.

Conclusion

The SDIL is a proven tool for reducing sugar consumption and improving health outcomes. Strengthening the levy offers a critical opportunity to further reduce sugar-related harm, particularly among children.

The FDS remains committed to contributing our public health expertise to working with policymakers to ensure future decisions continue to prioritise population wellbeing and health equity. 

References

¹Public Health England. 5-year-olds eat and drink their body weight in sugar every year [Internet]. GOV.UK; 2016 Jan 4 [cited 2025 Jun 12]. Available from: https://www.gov.uk/government/news/5-year-olds-eat-and-drink-their-body-weight-in-sugar-every-year

²Public Health England. Sugar reduction: Soft drinks industry levy 2015 to 2024 [Internet]. London: PHE; [cited 2025 Jun]. Available from: https://fingertips.phe.org.uk/static-reports/obesity-physical-activity-nutrition/sugar-reduction-drinks-2015-2024.html

³Royal College of Surgeons of England. Dental Surgeons: too many children admitted to hospital for tooth decay [Internet]. 2024 [cited 2025 Jun]. Available from: https://www.rcseng.ac.uk/news-and-events/media-centre/press-releases/fds-dental-admissions-sept-24/#:~:text=Tooth%20decay%20remains%20the%20leading,2024%20due%20to%20tooth%20decay

⁴Public Health England. National Dental Epidemiology Programme for England: Oral health survey of 5-year-old children 2022 [Internet]. 2023 [cited 2025 Jun]. Available from: https://www.gov.uk/government/statistics/oral-health-survey-of-5-year-old-children-2022/national-dental-epidemiology-programme-ndep-for-england-oral-health-survey-of-5-year-old-children-2022

⁵NHS Digital. National Child Measurement Programme, England – 2023/24 School Year [Internet]. 2024 [cited 2025 Jun]. Available from: https://digital.nhs.uk/data-and-information/publications/statistical/national-child-measurement-programme/2023-24-school-year

⁶NHS Digital. Health Survey for England 2022, Part 2: Adult overweight and obesity [Internet]. Leeds: NHS Digital; 2024 [cited 2025 Jun 13]. Available from: https://digital.nhs.uk/data-and-information/publications/statistical/health-survey-for-england/2022-part-2/adult-overweight-and-obesity

⁷Obesity Health Alliance. More than half of children set to be living with overweight or obesity in nine parts of England by 2035, new study warns [Internet]. London: Obesity Health Alliance; 2024 Jun 25 [cited 2025 Jul 22]. Available from: https://www.obesityalliance.co.uk/news/more-than-half-of-children-set-to-be-living-with-overweight-or-obesity-in-nine-parts-of-england-by-2035-new-study-warns

⁸HMRC. HMT-HMRC Soft Drinks Industry Levy Review [Internet]. 2024 [cited 2025 Jun]. Available from: https://www.gov.uk/government/publications/soft-drinks-industry-levy-review/hmt-hmrc-soft-drinks-industry-levy-review

⁹UK Department of Health and Social Care. Childhood obesity: a plan for action [Internet]. London: GOV.UK; 2016 [cited 2025 Jun 13]. Available from: https://www.gov.uk/government/publications/childhood-obesity-a-plan-for-action/childhood-obesity-a-plan-for-action

¹⁰Rogers NT, Cummins S, Forde H, Jones CP, Mytton O, Rutter H, Sharp SJ, Theis D, White M, Adams J. Associations between trajectories of obesity prevalence in English primary school children and the UK soft drinks industry levy: an interrupted time series analysis of surveillance data. PLoS Med. 2023;20(1):e1004160. doi:10.1371/journal.pmed.1004160.

¹¹Watt S. What is the impact of the UK soft drinks industry levy on childhood tooth decay? Evid Based Dent 2024;25:91–92. https://doi.org/10.1038/s41432-024-01025-3

¹²HM Revenue & Customs, HM Treasury. Strengthening the Soft Drinks Industry Levy [Internet]. London: GOV.UK; 2025 Apr 28 [cited 2025 Jun 23]. Available from: https://www.gov.uk/government/consultations/strengthening-the-soft-drinks-industry-levy.

¹³HM Revenue & Customs. Soft Drinks Industry Levy Statistics commentary 2024 [Internet]. 2024 [cited 2025 Jun]. Available from: https://www.gov.uk/government/statistics/soft-drinks-industry-levy-statistics/soft-drinks-industry-levy-statistics-commentary-2021

¹⁴World Health Organization. Fiscal Policies for Diet and Prevention of Noncommunicable Diseases: Technical Meeting Report [Internet]. 2016 [cited 2025 Jun]. Available from: https://www.who.int/publications/i/item/9789241511247

¹⁵Moynihan PJ, Kelly SAM. Systematic review of the effect on caries of sugars intake: ten‑year update [Internet]. J Dent Res. 2022;101(9):1034–1045 [cited 2025 Jun]. Available from: https://doi.org/10.1177/00220345221082918

¹⁶Public Health England. Delivering better oral health: an evidence‑based toolkit for prevention (v4) [Internet]. London: PHE; [cited 2025 Jun]. Available from: https://www.gov.uk/government/publications/delivering-better-oral-health-an-evidence-based-toolkit-for-prevention