Independent report

SACN annual report 2023 - summary

Published 29 February 2024

Foreword

It is my pleasure to introduce the 23rd annual report of the Scientific Advisory Committee on Nutrition (SACN), which covers the work of the committee in 2023. This is my fourth report as chair of SACN since taking over the role in 2020.

It has been a busy year. July 2023 saw publication of SACN’s report on ‘Feeding young children aged 1 to 5 years’. This report covers the period from 1 to 5 years of age (12 to 60 months) and accompanies SACN’s report on ‘Feeding in the first year of life’, which was published in 2018.

Consideration of the evidence was primarily focused on systematic reviews and meta-analyses of randomised controlled trials, prospective cohort studies and non-randomised studies of interventions. SACN also considered evidence from large national surveys. In parallel, the Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment (COT) considered the risks of toxicity from chemicals in the diet of young children aged 1 to 5 years.

SACN concluded that the current diet of young children in the UK does not meet current dietary recommendations for several nutrients. SACN made a number of dietary recommendations for consideration, as well as recommendations to government on strategies, actions and monitoring. Key changes to existing advice include that:

• current population dietary guidelines, as depicted in the Eatwell Guide, should apply from around 2 years old (rather than from 5 years old)
• recommendations on average intake of free sugars should apply from one year of age rather than 2 years old

SACN has also recommended that both whole and semi-skimmed cows’ milk can be given as a main drink from age one year. These recommendations have subsequently been endorsed by government. Research recommendations made in this report were the basis of a National Institute for Health and Care Research (NIHR) Policy Research Programme research call on nutrition in early years published in autumn 2023.

I would like to thank Professor Ken Ong for his support as chair of the SACN subgroup on maternal and child nutrition (SMCN), and all other members of SMCN for their invaluable expertise and input in producing this report.

July 2023 also saw the publication of the ‘SACN statement on processed foods and health’. This position statement:

• evaluated existing classifications of processed foods, including the NOVA ‘ultra-processed food’ (UPF) classification
• evaluated the suitability of methods to apply food processing definitions as a dietary exposure
• considered the availability and quality of evidence associating different forms or levels of food processing with health outcomes
• scoped future work on the topic

SACN concluded that the association between higher consumption of (ultra-) processed foods and adverse health outcomes is concerning - however, limitations in the available evidence mean that it is unclear whether these foods are inherently unhealthy due to processing or because a large majority of processed foods are high in calories, saturated fat, salt and/or sugar.

Given SACN’s concerns, the committee has added the topic of processed foods to its watching brief and will consider it at the next horizon scan meeting in June 2024. 

SACN also made a number of research recommendations and the Office for Health Improvement and Disparities (OHID) is discussing, with UK funders of research priority areas, how to improve the evidence relating to this topic.

Throughout 2023:

• the nutrition and maternal health working group (NMHWG) has progressed its risk assessment on maternal health
• the joint working group with COT has made good progress on its benefit:risk assessment on plant-based drinks (PBD) consumption
• SACN has progressed a rapid review of international approaches to vitamin D fortification

SACN is aiming to consult on or publish these areas of work in 2024.

The subgroup on SACN framework and methods for evidence evaluation has also continued to review the current SACN framework and published an updated SACN framework in February 2023, as well as providing methodological support to SACN, SMCN and SACN’s various working groups.

SACN also began consideration of the World Health Organization (WHO)’s guideline on the use of non-sugar sweeteners.

This year saw a change to the membership of SACN. We welcomed a new lay member to the committee, Mr Harry McDermott, as Mrs Gemma Paramor stood down from the committee after 10 years of service. I would like to thank Mrs Paramor for her contributions and insights over the years, and wish her well for the future.

I would like to give special thanks to Professor Julie Lovegrove for providing much appreciated support as the deputy chair.

Finally, I would like to thank members of the main committee, its subgroups and working groups, and the secretariat, for their commitment to the work of SACN in 2023.

Professor Ian Young, chair

About the committee

The role of SACN is to provide independent scientific advice on and risk assessments of nutrition and related health issues. It advises the 4 UK health departments, and other government departments and agencies.

Members are appointed as independent scientific experts on the basis of their specific skills and knowledge. The committee also includes 2 lay members.

SACN is a committee of OHID within the Department of Health and Social Care (DHSC) supported in its work by a secretariat based in OHID.

The secretariat has scientific expertise that enables it to work closely with SACN members to draft risk assessments.

SACN’s terms of reference are provided in annex 1 of the full report.

Openness

SACN is committed to values of openness and transparency.

Where possible, the committee’s main meetings are held in open session and external observers have the opportunity to ask questions at the close of the meeting.

However, meeting sessions relating to ongoing evidence evaluations and all working group and subgroup meetings are closed to external observers. This is to allow unconstrained discussion of the evidence and formulation of draft conclusions and recommendations before these are shared and finalised.

The agenda and papers for the open sessions of main committee meetings are published on the SACN group page approximately 2 weeks before a meeting. Once agreed by members, the minutes of SACN, working group and subgroup meetings are also published on the SACN group page.

Most SACN meetings this year were held virtually, except for the SACN meeting held on 22 June and the SMCN meeting held on 4 May, which were held in person with the option for members to attend online.

Membership

Details of membership of the committee, its working groups and subgroups can be found in annex 2 of the full report. Biographies of all members are provided in annex 3.

Remuneration and committee finances

Remuneration and committee finances are shown in annex 4 of the full report.

Declarations of interest

SACN members are required to declare any potential or perceived interests at the time of their appointment, and any changes to their interests at the start of every meeting (of SACN, its subgroups and working groups). Any changes to a member’s declaration of interests are recorded in the minutes of the meeting.

In the interest of objectivity, SACN includes lay members and meetings are attended by observers from departments with responsibility for nutrition policy in each UK country. Further details of SACN’s policy on openness and transparency can be found in the SACN Code of Practice.

A register of members’ interests is available on the SACN group page. An updated version of the register is published shortly before each main SACN committee meeting. A snapshot of the register of interests is included in annex 5 of the full report.

Procedures

Meeting agendas are compiled from a number of sources including:

• outstanding items from previous meetings
• items suggested by the committee
• outside bodies including other scientific advisory committees
• items brought forward from the committee’s work programme

Updates from SACN’s subgroups and working groups, and government updates from all 4 nations are regular features on the agenda.

SACN’s work in 2023

This is the 23rd annual report of SACN and covers the calendar year 2023.

The main committee met 3 times on 16 March, 22 June and 23 November 2023.

The SMCN met 3 times on 10 February, 4 May and 6 October 2023. 

The subgroup on SACN framework and methods for evidence evaluation met once on 18 October 2023.

The NMHWG met twice on 25 May and 1 November 2023.

The joint SACN and COT working group on PBD met once on 4 October 2023.

The vitamin D fortification working group did not meet in 2023.

Work programme

The following topics were on the committee’s main work programme:

• feeding children aged 1 to 5 years
• processed foods and health
• nutrition and maternal health
• PBD
• vitamin D fortification
• review of the WHO guideline on use of non-sugar sweeteners (NSS)
• SACN framework and methods for evidence evaluation

SACN has kept a watching brief on the following items:

• processed foods and health
• sweeteners
• plant-based diets
• protein
• omega-3 fatty acids
• calcium
• folic acid
• nutrition and COVID-19

The committee has also kept the following items on a watching brief, but as a lower priority:

• magnesium
• selenium

At the 2022 horizon scan meeting, SACN agreed to take forward the following pieces of work:

• a step-wise approach to considering wholegrain - firstly to agree a definition
• a rapid review of iodine (to be started once resources allow)
• consideration of vitamin D recommendations for dark-skinned population groups (expansion of current vitamin D fortification working group)

At the previous horizon scan, the committee also agreed to consider iron bioavailability.

The next SACN horizon scan meeting is due to take place on 20 June 2024, when the timing for these pieces of work will be discussed.

Processed foods and health

SACN considered the topic of UPF at its horizon scan meeting in June 2022. Members noted that it would be timely to consider this issue since there was increasing discussion and debate regarding the implications of food processing on health. In autumn 2022, OHID at DHSC asked that SACN expedite this work.

In July 2023, SACN published its ‘Statement on processed foods and health’.

The committee has added the topic of processed foods to its watching brief and will consider this at its next horizon scan meeting in June 2024.

Sweeteners

SACN discussed the issue of sweeteners at its horizon scan meeting in June 2022 and agreed to add the topic to its watching brief to consider the evidence base as it develops, and any available information on trends and use of sweeteners.

In May 2023, WHO published a guideline on NSS. This guideline included the following conditional recommendation that NSS not be used as a means of achieving weight control or reducing the risk of non-communicable diseases.

At the SACN meeting in June 2023, members agreed to review the evidence supporting the WHO guideline in the local national context, in order to consider the appropriateness of WHO’s conditional recommendation for the UK.

SACN members discussed this item at the November 2023 SACN meeting and are due to discuss this again at SACN’s meeting in June 2024.

SACN’s subgroups and working groups

The committee operates through subgroups and working groups comprising SACN members and co-opted specialists (for more information, see the SACN Code of Practice and SACN framework and methods for the evaluation of evidence that relates food and nutrients to health).

These groups:

• develop recommendations and advice on specific areas of public health nutrition
• report back on progress to the main committee at each SACN meeting

Subgroup on maternal and child nutrition (SMCN)

Background

SMCN is a specialist standing group that advises government on issues relating to maternal and child nutrition - an area in which health departments need regular scientific advice for policy-making and regulatory purposes.

The subgroup is chaired by SACN member Professor Ken Ong. 

Terms of reference

The terms of reference for SMCN are to advise, through SACN, on aspects of maternal and child diet and nutrition, when advice is sought by OHID, the UK health departments or SACN.

Activity

The subgroup held 3 meetings in 2023 (10 February, 4 May and 6 October 2023).

SMCN focused on the progression and publication of its risk assessment on feeding children aged 1 to 5 years.

SACN’s final report ‘Feeding young children aged 1 to 5’ was published on 4 July 2023.

The report forms part of a wider piece of work that considered the scientific basis of current recommendations for feeding children up to 5 years of age, the first part of which - the ‘Feeding in the first year of life’ report - was published in 2018.

The terms of reference for this work are to:

• review the scientific basis of current recommendations for complementary and young child feeding up to 5 years (60 months) of age. This second report covers young children aged 1 to 5 years of age
• consider evidence on developmental stages, and other factors that influence eating behaviour and diversification of the diet in the early years
• review the nutritional basis for current dietary recommendations applying to breastfeeding mothers (where relevant to the health of the infant)
• make recommendations for policy, practice and research

Subgroup on SACN framework and methods for evidence evaluation (framework subgroup)

Background

An updated SACN framework was published in February 2023. This followed the subgroup’s consideration and review of processes for evaluating the evidence, scope and level of evaluation, and grading the certainty of evidence. The framework is subject to regular review and may be updated as required.

The framework subgroup is chaired by SACN member Professor Julie Lovegrove. 

Terms of reference

The terms of reference of the framework subgroup are to provide ongoing methodological support to SACN and its subgroups and working groups and to SMCN, including keeping the SACN framework under review to ensure it continues to be fit for purpose.

Activity

The framework subgroup held one meeting in 2023 (18 October 2023).

At the meeting, members discussed issues arising from a training session (25 May 2023), attended by members of SACN, SMCN and the NMHWG, on using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach to assess the certainty of evidence in future SACN evidence evaluations. They also provided advice and addressed specific questions relating to grading the certainty of evidence for the SACN report on ‘Nutrition and maternal weight outcomes’.

Members also considered the process for publishing updates to the SACN framework, and agreed that each version could include both the year and version number, and that any changes were recorded in an annex that could be regularly updated with any key amendments.

Subgroup members agreed that subsequent meetings would be held on an as needed basis when advice is required by SACN or its working groups on any methodological issues.

Nutrition and maternal health working group (NMHWG)

Background

In 2019, SACN agreed to undertake a risk assessment on nutrition and maternal health and to establish a working group. The impact of COVID-19 on secretariat capacity meant that this work was paused in 2020 and fully resumed in 2022.

Terms of reference

The terms of reference are for the working group to:

• review the scientific basis of current dietary recommendations for women during preconception, pregnancy and up to 24 months after delivery in relation to maternal health and pregnancy-related outcomes (that is maternal outcomes during pregnancy, childbirth and up to 24 months after delivery)
• make recommendations based on the review of the evidence

The working group is chaired by SMCN member Professor Ann Prentice OBE.  

Activity

The NMHWG held 2 meetings in 2023 (25 May and 1 November 2023).

This year, the working group has reviewed and discussed the draft ‘Nutrition and maternal weight outcomes’ report, including the presentation of the evidence in the draft and the overall structure and the evidence summaries from the identified evidence. Members have also received an update on the COT work being undertaken to support this risk assessment. Members agreed the key next steps.

At the 8th meeting on 1 November 2023, the working group:

• reviewed and discussed the draft chapter on intakes of energy and nutrients and nutritional status measures in girls and women of childbearing age, and additional analyses from the National Diet and Nutrition Survey
• reviewed and discussed the draft ‘Nutrition and maternal weight outcomes’ report including the SR evidence
• received an update on the framework subgroup’s consideration of grading the certainty of the evidence for this report
• received an update on the COT work being undertaken to support this risk assessment and agreed the key next steps. This topic was discussed at the SACN meeting in November 2023

A meeting was held on 7 February 2024.

The aim is to publish a draft report for public consultation in 2024.

Joint SACN and COT working group on plant-based drinks (PBD)

Background

SACN and SMCN were asked to consider whether consumption of PBD by children under 5 years of age would present a risk to health from a nutritional perspective.

The COT examined the potential adverse toxicological health effects of soya, oat and almond drinks consumed as part of the infant and young child diet in its ‘Overarching statement on consumption of plant-based drinks in children aged 6 months to 5 years of age (2021)’.

A joint working group, comprising an independent chair (Professor Mike Kelly) and members of COT, SACN and SMCN, was established.

Given the increasing availability and consumption of PBD in the UK, the committees also agreed that it would be beneficial to widen the benefit:risk assessment to cover the general population.

Terms of reference

The terms of reference are for the joint working group to:

• conduct a benefit:risk assessment considering both toxicological and nutritional aspects associated with the consumption of PBD by the UK population
• provide integrated advice to the UK health departments based on this benefit:risk assessment

Activity

The joint SACN and COT working group has held one meeting in 2023 on 4 October 2023.

To date, the joint working group has considered:

• the assessments conducted to date by SACN, SMCN and COT on nutritional and toxicological considerations associated with PBD consumption, respectively
• data on consumption and purchase of PBD
• findings from a rapid scoping search exploring the available evidence on PBD and nutrition-related outcomes
• iterations of a substitution analysis modelling the impact on nutrient intakes of replacing all cows’ milk with PBD (soya, oat and almond, and 3 scenarios for each: ideal, typical and worse case) and also with water in different population age groups
• the use of the Benefit-Risk Analysis for Foods (BRAFO) methodology for assessing the evidence informing this risk assessment

A call for evidence was issued for one month from 11 March to 10 April 2022.

At the meeting on 4 October 2023, members reviewed the overall content and structure of the draft report (in particular, how to integrate nutritional and toxicological considerations), and discussed the draft conclusions and recommendations. An update was discussed at the SACN meeting in November 2023.

A meeting was held on 14 February 2024.

The aim is for a draft joint SACN and COT statement to be published for public consultation in 2024.

Vitamin D fortification working group

Background

The vitamin D fortification working group was established to undertake a rapid review, in response to a request from the Secretary of State for Health and Social Care, to consider options for improving vitamin D intakes and vitamin D status of the UK population and for reducing disparities.

The SACN vitamin D fortification working group aims to provide scientific advice on the potential of mandatory vitamin D food fortification for the UK population to achieve UK dietary recommendations for vitamin D.

At the SACN horizon scan meeting in June 2022, it was agreed that the working group should review evidence published since SACN’s 2016 ‘Vitamin D and health’ report on vitamin D requirements of dark-skinned population groups.

Terms of reference

The terms of reference are for the working group to:

1. Consider the potential impact of mandatory fortification of foods with vitamin D. This will include:

• consideration and interpretation of models to assess the potential impact of mandatory vitamin D fortification on achievement of UK dietary recommendations and avoidance of intakes above tolerable upper intake levels
• review of the experiences from countries with existing vitamin D fortification programmes, and their impact on vitamin D intakes and vitamin D status
• consideration of factors that could affect the potential efficacy of vitamin D fortification in the UK, including habitual diet, life stage, inequalities, ethnicity and UVB sunshine exposure
• review of the efficacy of different forms of vitamin D for use as a food fortificant

2. Consider whether there is evidence published since SACN’s 2016 ‘Vitamin D and health’ report that would impact upon the existing recommendations for vitamin D intake and vitamin D status.

Activity

The first working group meeting was held on 4 October 2022. Members discussed the first draft of the rapid scoping review of international vitamin fortification practices, as well as the approach to reviewing the evidence for the rapid review of the efficacy of different forms of vitamin D (D2 and D3).

An update of this work was presented to SACN at the November 2023 meeting for discussion. The aim is to publish this paper early in 2024.

The working group will consider the timeline for reviewing the evidence regarding vitamin D requirements of dark-skinned population groups at the next horizon scan meeting in summer 2024.