Overview

This guideline covers vitamin D use in the context of COVID-19. It is for adults, young people and children in hospitals and community settings. Vitamin D is important for bone and muscle health. It may also have a role in the body’s immune response to respiratory viruses.

When using this guideline, follow the usual professional guidelines, standards and laws (including those on equalities, safeguarding, communication and mental capacity), as described in making decisions using NICE guidelines.

See also the NICE guideline on Vitamin D: supplement use in specific population groups.

This guideline is for:

• health and care practitioners
• health and care staff in hospital and community settings
• commissioners

The recommendations bring together:

• evidence from published literature on vitamin D supplementation for preventing or treating COVID-19, associations of vitamin D status with COVID-19, and indirect evidence on vitamin D supplementation for preventing acute respiratory tract infection in the general population (from the updated Scientific Advisory Committee on Nutrition rapid review)
• existing national guidance and policies (including UK government advice on taking a vitamin D supplement)
• advice from specialists working in the NHS from across the UK, including nutritionists, intensive care specialists, public health physicians, microbiologists, general practitioners and pharmacists.

We developed this guideline with the Scientific Advisory Committee on Nutrition and Public Health England using the interim process and methods for guidelines developed in response to health and social care emergencies. We will review and update the recommendations as the knowledge base develops.

Recommendations

1.1.

Encourage people to follow UK government advice on taking a vitamin D supplement to maintain bone and muscle health. The advice is that:

• Adults (including women who are pregnant or breastfeeding), young people and children over 4 years should consider taking a daily supplement containing 10 micrograms (400 units; also called international units [IU]) of vitamin D between October and early March because people do not make enough vitamin D from sunlight in these months.
• Adults, young people and children over 4 years should consider taking a daily supplement containing 10 micrograms (400 units) of vitamin D throughout the year:

  –

  if they have little or no sunshine exposure including because they:

  ◇

  are not often outdoors, for example, if they are frail, housebound or living in a care home

  ◇

  usually wear clothes that cover up most of their skin when outdoors

  ◇

  are spending most of their time indoors because of the COVID-19 pandemic

  –

  if they have dark skin, for example, if they are of African, African-Caribbean or south Asian family origin, because they may not make enough vitamin D from sunlight.

• Babies from birth to 1 year should have a daily supplement containing 8.5 micrograms (340 units) to 10 micrograms (400 units) of vitamin D throughout the year if they are:

  –

  breastfed

  –

  formula-fed and are having less than 500 ml of infant formula a day (because infant formula is already fortified with vitamin D).

• Children aged 1 year to 4 years should have a daily supplement containing 10 micrograms (400 units) of vitamin D throughout the year.
• Some people have a medical condition that means they cannot take vitamin D or should take a different amount from the general population.

1.2.

Do not offer a vitamin D supplement to people solely to prevent COVID-19, except as part of a clinical trial.

1.3.

Do not offer a vitamin D supplement to people solely to treat COVID-19, except as part of a clinical trial.

Recommendation for research

We have made the following recommendation for research.

Rationale

Context

Vitamin D is important for bone and muscle health. It may also have a role in the body’s immune response to respiratory viruses. Sunlight exposure is the main source of vitamin D for most people in the UK during summer months. But, between October and early March, people in the UK do not make enough vitamin D from sunlight. Vitamin D is also found in a small number of foods and can be obtained from supplements. The 2 key forms of vitamin D, D3 (colecalciferol) and D2 (ergocalciferol), are licensed for preventing and treating vitamin D deficiency. They are not specifically licensed for preventing or treating any infection, including SARS-CoV-2 that causes COVID-19.

Vitamin D status is determined by measuring serum concentrations of 25 hydroxyvitamin D (25[OH]D), the major circulating metabolite of vitamin D. Existing UK government recommendations on vitamin D are based on advice from the Scientific Advisory Committee on Nutrition (SACN). To protect bone and muscle health, the SACN vitamin D and health report recommends that serum 25(OH)D concentration should not fall below 25 nmol/litre at any time of the year. To achieve this, SACN recommends a reference nutrient intake of 10 micrograms (400 units; also called international units [IU]) of vitamin D daily for the UK population aged 4 years and above. This is the average amount needed by 97.5% of the population to maintain a serum concentration of 25 nmol/litre when UVB sunshine exposure is minimal. UK government advice on taking a vitamin D supplement includes:

• 10 micrograms (400 units) of vitamin D daily for everyone in the UK aged over 4 years between October and early March, and
• 10 micrograms (400 units) of vitamin D daily throughout the year for people whose serum 25(OH)D concentrations may not reach 25 nmol/litre through sunlight alone.

The dose of vitamin D in units can be calculated by multiplying the number of micrograms by 40; for example, 10 micrograms is equivalent to 400 units. This guideline uses ‘units’ instead of ‘international units’ or ‘IU’ for doses of vitamin D. This is consistent with the BNF guidance on prescription writing, and stems from the preferred convention of using ‘units’ because of safety concerns about using ‘IU’ in prescribing.

There are services supplying free vitamin D supplements to some population groups. For example, there is an NHS service supplying free daily vitamin D supplements for people at high risk (clinically extremely vulnerable) from COVID-19. This service has been set up because it is particularly important for people who have been indoors more over the spring and summer while shielding to take vitamin D for bone and muscle health. Women and children who qualify for the Healthy Start scheme can also get free supplements containing vitamin D.

Your responsibility: The recommendations in this guideline represent the view of NICE, arrived at after careful consideration of the evidence available. When exercising their judgement, professionals and practitioners are expected to take this guideline fully into account, alongside the individual needs, preferences and values of their patients or the people using their service. It is not mandatory to apply the recommendations, and the guideline does not override the responsibility to make decisions appropriate to the circumstances of the individual, in consultation with them and their families and carers or guardian.

Local commissioners and providers of healthcare have a responsibility to enable the guideline to be applied when individual professionals and people using services wish to use it. They should do so in the context of local and national priorities for funding and developing services, and in light of their duties to have due regard to the need to eliminate unlawful discrimination, to advance equality of opportunity and to reduce health inequalities. Nothing in this guideline should be interpreted in a way that would be inconsistent with complying with those duties.

Commissioners and providers have a responsibility to promote an environmentally sustainable health and care system and should assess and reduce the environmental impact of implementing NICE recommendations wherever possible.