Background
In 2016, the Scientific Advisory Committee on Nutrition (SACN) recommended that the UK population aged 4 years and over should have a daily intake of 10 μg (400 IU) of vitamin D to maintain adequate blood levels and prevent poor musculoskeletal health. This recommendation came in response to emerging evidence that insufficient vitamin D levels can lead to conditions such as rickets and osteomalacia, and it acknowledged that meeting these levels through diet alone can be challenging in the UK due to limited sunlight exposure, particularly during the autumn and winter months.
A recent article in Nutrition Bulletin discussed whether the UK should routinely fortify food and drinks with vitamin D. The discussion is timely given the widespread vitamin D deficiency in the UK, particularly among certain groups such as older adults, people from Black and South Asian communities, and those with limited outdoor access. The article explores the potential benefits of fortification, which include improving overall vitamin D status and reducing health disparities.
The Current Situation
Despite these recommendations and a history of voluntary fortification efforts (e.g., margarine was fortified with vitamin D from 1940 to 2013), recent data from the National Diet and Nutrition Survey (NDNS) shows that many people in the UK are still not meeting the recommended intake levels. A substantial proportion of the population, particularly those with limited sun exposure and certain ethnic groups, remains at risk of vitamin D deficiency. This has prompted discussions about whether mandatory fortification of foods and drinks with vitamin D could be a more effective strategy.
Lessons from Other Countries
Several countries have implemented vitamin D fortification policies, with varying levels of success:
1. Finland: Finland has a mandatory fortification policy for milk and some other foods. This policy, combined with an increase in supplement use, has led to a significant improvement in the vitamin D status of the Finnish population. The proportion of individuals with vitamin D levels below 30 nmol/L has dropped from 12% to less than 1%.
2. Sweden: Sweden has implemented high levels of fortification in margarine, with levels ranging between 19.5 to 21 μg per 100 g. This has been effective in improving the vitamin D status of the population.
3. Canada: Canada mandates the fortification of milk and some other foods with vitamin D. The policy specifies that both vitamin D2 and D3 can be used for fortification, and it has been effective in raising the overall vitamin D levels in the population.
4. Australia: Australia’s fortification policy includes margarine and other foods, with varying fortification levels. This approach has contributed to a better vitamin D status across the population.
5. Norway and the United States: These countries have voluntary fortification policies. The US, for example, allows fortification of milk and breakfast cereals, which has helped to improve vitamin D intake among certain groups.
These experiences suggest that well-designed and effectively implemented fortification policies can significantly improve population vitamin D status.
Considerations for the UK
1. Form of Vitamin D: The choice between vitamin D2 and D3 is crucial. Evidence indicates that vitamin D3 is more effective in raising blood levels of 25(OH)D compared to vitamin D2. Therefore, if the UK adopts a fortification policy, using vitamin D3 might be preferable, particularly in foods consumed by the general population.
2. Food Vehicles: Selecting appropriate foods for fortification is essential. In Finland, the success of fortification is partly due to its wide adoption in commonly consumed products. The UK might consider fortifying widely consumed foods like milk, breakfast cereals, and fat spreads.
3. Population Groups: Special attention should be given to high-risk groups such as those with limited sun exposure, individuals with dark skin, and people living in lower socio-economic conditions. Fortification strategies should ensure that these groups benefit from the policy.
4. Monitoring and Evaluation: Any fortification policy should include mechanisms for monitoring its impact on vitamin D status across different population groups and ensuring that upper intake levels are not exceeded.
Recommendations
1. Pilot Studies: Before implementing nationwide fortification, the UK could conduct pilot studies to assess the efficacy and acceptability of different fortification strategies. These studies could help identify the most effective food vehicles and fortification levels.
2. Public Education: Alongside fortification, a public education campaign should be launched to increase awareness of vitamin D and its sources. This could improve overall compliance and understanding of the importance of adequate vitamin D levels.
3. Review and Adaptation: The policy should be regularly reviewed and adapted based on ongoing research and monitoring. This will ensure that the fortification strategy remains effective and relevant to the population’s needs.
4. Collaboration: Engaging with stakeholders including food producers, healthcare professionals, and community organizations will be crucial for the successful implementation and acceptance of a fortification policy.
Conclusion
As the UK grapples with persistent issues of vitamin D deficiency despite existing recommendations and voluntary fortification, exploring mandatory fortification of foods and drinks emerges as a viable strategy. By learning from international experiences and addressing local needs, the UK could enhance its approach to improving vitamin D status and, ultimately, public health. The decision will require careful consideration, robust evidence, and a multi-faceted approach to ensure that all population groups benefit from improved vitamin D intake.
