The UK's official guidelines for how much iron people need are based on a 1991 assumption that the body absorbs 15% of dietary iron—an assumption that no longer fits a population eating more plant-based meals and fewer animal products. This matters because iron is essential for red blood cell production and childhood development, yet current dietary reference values (DRVs) may be inaccurate for groups like young children, people with obesity, or those on plant-based diets. Iron bioavailability—the proportion actually absorbed—varies by diet type, and plant-based iron is harder for the body to use. The researchers will systematically review physiological iron requirements for children aged 0–18, then model updated bioavailability values using nationally representative UK dietary data. If successful, the findings will be handed to the UK Scientific Advisory Committee on Nutrition (SACN) to revise official iron intake recommendations. Updated DRVs would ensure dietary guidelines apply to the entire population, not just those eating meat-heavy diets. This could quietly improve public health by preventing iron deficiency in vulnerable groups without anyone needing to change what they eat—the guidelines themselves will simply become more accurate.
View original technical description
Iron is an essential nutrient for human health. It is needed for the production of red blood cells, and for supporting growth and development during early life. An individual s iron status depends on both the quantity and bioavailability of iron in the diet. Iron bioavailability refers to the proportion of dietary iron that is absorbed and utilised by the body. Dietary reference values (DRVs) guide iron intake assessment and interventions at the individual and population level. DRVs for iron are derived by converting physiological requirements into dietary iron intakes using an estimated dietary iron bioavailability value in the target population. Current UK DRVs for iron were set in 1991 based on an assumed 15% dietary iron bioavailability. Since then, our knowledge of physiological iron requirements in different population groups (e.g. young children) has improved, and new methods for estimating dietary iron bioavailability are now available. Furthermore, dietary patterns in the UK population have become more diverse due to increased multiculturalism and a shift towards more plant-based diets. It is therefore important, and timely, to re-assess current UK DRVs for iron. The proposed research aims to generate iron bioavailability values for a range of diets applicable to the UK population, and projected iron DRVs for different UK population groups. To achieve this, the proposed research will: Systematically review existing evidence on physiological iron requirements for children aged 0–18 years to inform re-assessment of iron DRVs for paediatric populations in the UK. Systematically review existing evidence on dietary iron bioavailability to inform re-assessment of iron DRVs for the relevant UK population groups. Use nationally representative data to undertake detailed modelling to generate a range of dietary iron bioavailability values for relevant UK population groups. Use the newly estimated iron bioavailability and physiological iron requirement values to model projected DRVs for different UK population groups. The proposed research is timely, as the UK population continues to shift from diets high in meat and animal products to more plant-based diets. As the bioavailability of iron may differ by diet type, and in groups with certain physiological characteristics (e.g. people living with overweight/obesity), updated DRVs will ensure dietary guidelines are applicable to the entire UK population. Findings of the proposed research will be used by the UK Scientific Advisory Committee on Nutrition (SACN) to support the guidance they provide to the UK Government on dietary intake recommendations for the UK population. The research will be guided by an advisory group consisting of representatives from various stakeholder groups, including scientists with relevant expertise, nutrition professionals, policymakers and public representatives, and an independent patient and public engagement (PPIE) group. These groups will help inform the research plan, interpret and disseminate findings. Research findings will be shared widely through a project report, scientific publications, dedicated symposia targeted at nutrition and health professionals and key stakeholders, and through dissemination activities and resources aimed at the public and particularly relevant population groups (informed by our PPIE group).
Plain English summaries and category classifications on this site are generated by AI and may not perfectly reflect the original research.
Is something wrong? Let us know