Vitamin D Deficiency and Dementia

Can an extreme vitamin D deficiency increase the risk of developing dementia?

A recent study appearing in the journal Neurology supports the link between severe deficiency in vitamin D and an increased risk of developing dementia.

A team of researchers at the University of Exeter found that the higher the vitamin D deficiency, the higher the risk of developing dementia and Alzheimer's disease.

Study participants who were severely Vitamin D deficient were found to be more than twice as likely to develop Dementia and Alzheimer's disease.

Research revealed that those who were moderately deficient in vitamin D had a 53 per cent increased risk of developing dementia. This risk increased to 125 per cent in those who were severely Vitamin D deficient.

The research team was led by Dr Llewellyn who has said: “We expected to find an association between low Vitamin D levels and the risk of dementia and Alzheimer's disease, but the results were surprising - we actually found that the association was twice as strong as we anticipated.”

The exact mechanism is unknown, however vitamin D receptors are found in the brain and are thought to regulate neurotrophic factors which are involved in the maintenance of neurones.

The 3 Main Sources of Vitamin D are:

  • Exposure of skin to UV sunlight
  • Foods such as oily fish, egg yolks and cheese
  • Vitamin D Supplements

For older people, the skin can be less efficient at converting UV sunlight into Vitamin D. This making the elderly more likely to be deficient and reliant on other sources, such as food and supplements.

Dr Doug Brown, Director of Research and Development at Alzheimer's Society has said: "However, we're not quite ready to say that sunlight or vitamin D supplements will reduce your risk of dementia. Large scale clinical trials are needed to determine whether increasing vitamin D levels in those with deficiencies can help prevent the dementia from developing."

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