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Vitamin D. Vitamin D. Maintains bone structure Regulates the immune system Generated from sunlight exposure UVB wavelengths 20-30 mins exposure on the face and arms two or three times a week, April to October
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Vitamin D • Maintains bone structure • Regulates the immune system • Generated from sunlight exposure • UVB wavelengths • 20-30 mins exposure on the face and arms two or three times a week, April to October • People with darker skin pigmentation, obesity and the elderly synthesise less vitamin D.
Dietary sources of Vitamin D • Eggs • Oily fish • Shiitake and chanterelle mushrooms (Vitamin D2) • Yeast (Vitamin D2) • Cod liver oil (rich source of vitamin D3)
Link with MS • Month of birth • more prevalent in babies born in May, less in those born in November in Northern Europe due to low maternal exposure to sunlight during the winter months. ( Willer, C. etal 2005). • Lack of vitamin D during pregnancy and the early years of life could increase the risk of developing MS later in life. (Ramagopalan, S.V; etal, 2010) • Direct link between the variant gene HLA-DRB1*1501, can be switched on by vitamin D in the laboratory setting (Ramagopalan, S.V; etal, 2010) • CYP 27B1 mutated gene affects a key enzyme which leads to low levels of vitamin D (Ebers, G,. 2011) • Geographical distribution of MS correlates to sunlight exposure (Hypponen, E; and Power C, 2007)
Use of vitamin D in pregnancy All pregnant women should be advised to take vitamin D supplements during pregnancy and whilst breastfeeding (NICE antenatal care clinical guidelines 62; 2008) in order to reduce incidence of certain diseases in the unborn child
Research into vitamin D and MS • Recent small study identified potential link between lower levels of vitamin D and susceptibly to depression in MS (Knipperberg, S. et al 2010) • Studies are investigating the link between vitamin D levels and relapse rate (Wingerchuck, D.M; et al. 2005) • Prospective study on over 7 million US military personnel showed that high circulating levels of vitamin D was associated with a lower risk of MS. (Munger, K.L; et al, 2004) • Outdoor occupation is associated with decreased risk of MS (Westberg,M. et al 2009)
Other benefits of vitamin D • Recently found to reduce by about half the risk of several diseases • breast cancer, colon cancer, multiple sclerosis and type 1 diabetes (Garland, C. 2011) • May also have a role in the prevention of heart disease, stroke, hypertension, chronic pain, osteoarthritis plus many other conditions. (www.vitamindcouncil.org)
Dosage of vitamin D in MS • RDA is generally regarded as insufficient for use in MS and preventing MS • No consensus regarding recommended vitamin D dosage in MS • Expert opinion is divided and suggested doses range between 400-70,000 iu daily • European guidelines (2012) on safe tolerable upper limit state 4000 iu daily (100 mcg) for children over 11 years and adults • High doses of vitamin D3 may cause hypercalcaemia (Kimball, SM et al 2007)
Reported side effects of Vitamin D Itchy skin Vomiting Diarrhoea Constipation Urinary frequency Muscle discomfort • Excessive thirst • Metallic taste • Poor appetite • Weight loss • Bone pain • Tiredness • Sore eyes
Conclusion • There is a growing body of evidence linking vitamin D to prevention of MS • Further research is needed to establish; • Effect on disease course • Appropriate dosage • Who will benefit • Optimum time to commence vitamin D for maximum benefit