Vitamin D and Health

Preface
The Scientific Advisory Committee on Nutrition (SACN) previously considered the evidence on vitamin D and
health in 2007. It concluded that there were insufficient data at that time to reconsider the Dietary
Reference Values (DRVs) for vitamin D set by the Committee on Medical Aspects of Food and Nutrition Policy
(COMA) in 1991. Since vitamin D is synthesised in the skin when it is exposed to sunlight, COMA considered
that dietary intakes of vitamin D were not necessary for most of the UK population (aged 4-64y). It was
assumed that skin synthesis of vitamin D in the summer would be enough to cover requirements during the
winter. Reference Nutrient Intakes (RNI) were therefore set only for groups considered at risk of vitamin D
deficiency.
In 2010, SACN agreed to consider whether the DRVs for vitamin D intake were still appropriate in the context
of public health advice to stay out of the sun and to wear sunscreen and because a substantial amount of
new evidence had accumulated since its previous considerations.
In a change to previous advice, SACN is now recommending an RNI for vitamin D of 10 µg/d (400 IU/d),
throughout the year, for everyone in the general UK population aged 4y and above. The RNI of 10 µg/d
(400 IU/d) for the general UK population includes pregnant and lactating women and population groups at
increased risk of vitamin D deficiency. Since there were insufficient data to set RNIs for children aged under
4y, Safe Intakes 1 are being recommended for this age group (8.5-10 µg/340-400 IU per day for all infants
aged under 1y and 10 µg/400 IU per day for ages 1 up to 4y). The RNI/Safe Intakes have been developed to
ensure that the majority of the UK population has a satisfactory vitamin D status (as measured in the blood)
throughout the year, in order to protect musculoskeletal health. It was not possible to quantify and take
account of sunlight exposure in setting the DRVs because of the number of factors that affect endogenous
vitamin D synthesis.
Since it is difficult to achieve the RNI/Safe Intakes from natural food sources alone, SACN is also
recommending that the Government considers strategies to help the UK population consume the
recommended intakes of vitamin D.
I would like to thank all those individuals and organisations who provided comments on the draft version of
this report during the public consultation. All the comments were carefully considered before the report
was finalised and the process assisted SACN in refining and clarifying the text.
Completion of this report has been a long and challenging task for SACN because consideration of the
evidence was complicated by the fact that vitamin D is obtained from sunlight exposure as well as from food
and supplements. I want to thank the members of the SACN Working Group on Vitamin D for their
continuing commitment and their contributions to the report, especially the Chair, Professor Hilary Powers,
and the secretariat. I also want to thank Professor Ann Webb (Manchester University) and Professor Antony
Young (King’s College, London) for providing helpful advice and information on the photobiology of vitamin
D.
Dr Ann Prentice
Chair, Scientific Advisory Committee on Nutrition
2016
1 Safe Intakes were set by COMA if there were insufficient reliable data to set DRVs.
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