Vitamin D (Cholecalciferol)

Description A fat-soluble vitamin.
Function/ Used for Vitamin D helps the body to absorb and use calcium and phosphorus; which are essential for maintaining strong and healthy bones and teeth, as well as other body functions such as heart and muscle function.

Vitamin D is also important for blood clotting, the immune system and muscle growth, development and function.

Intake Recommended intake

EU NRV: 5µg (micrograms)


In July 2016 Public Health England published guidelines for vitamin D1:

·         Babies from birth to 1 year: 8.5-10µg/day all year round.

·         Children over 1 year and adults: 10 µg /day in the winter months

·         Pregnant and breastfeeding women and population groups at risk of vitamin D deficiency (those with minimal exposure to sunshine and those from minority ethnic groups with dark skin): 10 µg /day all year round


Chief Medical Officer recommendations are that all children aged six months to five years should take a daily supplement containing vitamins A, C and D.


UK average daily intake

Requirements vary depending on age and gender. The UK National Diet and Nutrition Survey lists up-to-date intake requirements and average intakes2.

As a supplement Available as a single supplement. Also commonly available as part of a multivitamin and mineral formula.

Different multivitamin and minerals products will vary in the percentage NRVs they include. People should always check the label for information about a specific product.

In 2018 the UK food supplements industry agreed a voluntary safe upper level of vitamin D for food supplements of 75µg. Read statement

Found in (dietary sources) Good food sources include full-fat dairy products, oily fish, egg yolks and fortified margarine.
Food alone is unlikely to provide sufficient vitamin D.
Vitamin D is also formed by the action of sunlight on the skin (from May to September in the UK).
Deficiency Vitamin D deficiency results in poor growth, bone pain and deformities (rickets in children and osteomalacia in adults), osteoporosis, gum disease, constipation and muscle weakness.5
Precautions and contraindications Vitamin D should be avoided in hypercalcaemia (high levels of calcium in the blood).

Safe Upper Level: there are differences of opinion.
In 2003 the UK Expert Group on Vitamins and Minerals set a safe upper level of 25µg for vitamin D in food supplements.
In 2010 the American Institute of Medicine set a safe upper intake level of 100µg for total vitamin D intake3
In 2012 the European Food Safety Authority set a safe upper intake level of 100µg for total vitamin D intake4

In 2018 the UK food supplements industry set a voluntary safe upper level of 75µg for vitamin D in food supplements which allows for dietary intakes of up to 25µg without exceeding the most widely accepted safe upper level.

Use in pregnancy and breastfeeding There is no evidence of adverse effects in pregnancy at normal intakes.
Interactions e.g. with other medications Anticonvulsants (used to prevent epileptic seizures) may reduce the effect of vitamin D by accelerating its metabolism.

The weight loss drug orlistat and cholesterol-lowering drugs can reduce the absorption of vitamin D and other fat-soluble vitamins (A, E and K).

Calcium may increase risk of hypercalcaemia.5,6

Adverse effects There is no risk of vitamin D toxicity from prolonged exposure to sunlight.

Excessive dietary intake may lead to hypercalcaemia, which can weaken the bones and damage the kidneys and heart.

References 1

2 Expert Group on Vitamins and Minerals, 2003.

3 Institutes of Medicine. Dietary reference Intakes for Calcium and Vitamin D. November 2010.

4 European Food Safety Authority. Scientific Opinion on the Tolerable Upper Intake Level of Vitamin D. June, 2012

5 Mason, P. Dietary Supplements. Pharmaceutical Press, London, 2001.

6 Gaby, A. R. A-Z Guide to Drug-Herb-Vitamin Interactions. HealthNotes 2006.