People genetically prone to low vitamin-D levels are at increased risk of multiple sclerosis, a large study suggests. The findings, based on the DNA profiles of tens of thousands of people of European descent, add weight to the theory that the sunshine vitamin may play a role in multiple sclerosis.
Scientists are already testing whether giving people extra vitamin D might prevent or ease MS. Experts say the jury is still out. It is likely that environmental and genetic factors are involved in this disease of the nerves in the brain and spinal cord, they say. And if you think you may not be getting sufficient vitamin D from sunlight or your diet, you should discuss this with your doctor. Taking too much vitamin D can also be dangerous.
Is important for healthy bones.We make it in our skin when we are exposed to sunlight, but some of it comes from our diet. Good food sources include oily fish, eggs, fortified breakfast cereals and fortified fat spreads.
Some people – the elderly, pregnant and breastfeeding women, babies, children under the age of five, and those who do not get much sun – may not get enough and need supplements. Research around the world already shows MS is more common in less sunny countries, further from the equator.
But it is not clear if this relationship is causal, other factors might be at play. To better understand the association, investigators at McGill University in Canada compared the prevalence of MS in a large group of Europeans with and without a genetic predisposition to low vitamin D.
This type of genetic variation is pretty random and so the assumption is that any link found should be trusted. The findings, published in the journal PLoS Medicine, indicated people with lower blood levels of a marker of vitamin D, due to their genetic predisposition, were significantly more likely to have MS than individuals without these genes.