Vitamin D supplementation: the way ahead

Vitamin D deficiency has been linked to increased risk of asthma, cancer and chronic pain, among other conditions. Now, a new study led by researchers from the University of Georgia associates low vitamin D levels with greater risk of seasonal affective disorder (SAD).

SAD is a form of depression that occurs during the winter months. Symptoms include feeling sad or anxious, fatigue, concentration problems, irritability and feelings of guilt and hopelessness. The research team – led by Alan Stewart of the College of Education at the University of Georgia – published their findings in the journal Medical Hypotheses.¹

This is the latest in a raft of studies linking health conditions to vitamin D deficiency. Vitamin D is important for keeping bones and teeth healthy. A lack of the vitamin can lead to deformities such as rickets in children, and a condition known as osteomalacia in adults, which causes pain and tenderness. In England, around a fifth of adults and a sixth of children – approximately 10 million people may have low vitamin D status.² This is partly because the main source for vitamin D is from natural sunlight, and for six months of the year – from mid-October to the beginning of April – there is no sunlight at the correct wavelength for skin to create vitamin D.

As a result NICE has called for wider availability of low-cost supplements that could help prevent health problems in millions of people at risk of vitamin D deficiency.² It recommends increasing access to vitamin D supplements, and raising awareness of the health problems associated with it, to address those who may be at risk. While people from at risk groups are advised to take a vitamin supplements, they do not always receive the information and support they need. For example, there is low uptake of the Healthy Start scheme, which provides free vitamin D supplements to pregnant and breastfeeding women.

Certain groups of people in the UK are also more likely to have a lack of vitamin D. These include pregnant women, children and older adults. People with darker skin are also at risk of having low vitamin D levels.

The guideline aims to increase the use of vitamin D supplements to prevent deficiency among those most at risk and it recommends that access to vitamin D supplements containing the recommended dose should be increased.²

Professor Mike Kelly, Director of the NICE Centre for Public Health, said: “Around 10 million people in England may have low vitamin D status and so could be at risk of health problem and they may not know it. People with darker skin are particularly at risk during winter months nearly 75% of adults from Asian or African and Caribbean backgrounds may have low vitamin D levels. People who are over 65 years old are another group at risk of having low vitamin D levels, and so are also at risk of conditions like osteomalacia – soft bones. NICE recommends making low cost vitamin D supplements widely available to people at risk of deficiency.”

NICE say that local authorities should also ensure supplements containing the recommended dose of vitamin D are available at all at-risk groups, in settings such as pharmacies, children’s centres and GP reception areas. In addition, they should consider providing free supplements for at-risk groups, and encourage pharmacies and other outlets selling supplements to stock the lowest cost vitamin D supplements and promote them to those at risk. Local public health teams, health and social care practitioners and voluntary and community groups working with at-risk groups should also increase people’s awareness of the importance of vitamin D for good health sources of vitamin D in the UK (from safe sun exposure, supplements and limited dietary sources).References

1. http://www.medical-hypotheses.com/article/S0306-9877%2814%2900335-1/abstract

2. https://www.nice.org.uk/guidance/ph56