Vitamin D, Polar Vortexes, and Multiple Sclerosis
As the Polar Vortex penetrates deep into the lower latitudes of the North American continent (again), it is difficult to contemplate exposing skin for cutaneous production of vitamin D. New research finds low serum 25(OH)D levels are a concern, especially for individuals with multiple sclerosis.
Multiple sclerosis (MS) is the most common cause of neurological disability in young adults worldwide and half of those affected in Europe (Kingwell et al, 2013). The highest prevalence rates are found in Scotland, Northern Ireland, and specific populations of Scandinavia. These are regions with long winters or cloudy, cool seasons. Because of geographic variations observed in the prevalence of MS, suboptimal vitamin D levels have been proposed to contribute to the development of MS.
Slomski reports that individuals with MS having serum 25(OH)D concentrations above 50 nmol/L in the first year after the first neurological episode have a 57% lower risk of new active brain lesions and lower rate of relapse. These results come from a randomized, controlled trial (RCT) testing the impact of early vs delayed drug treatment (interferon beta-1b) reported in January. These are observational findings. They do not demonstrate cause and effect. Direct evidence will be forthcoming because a search of ‘vitamin D and multiple sclerosis’ in ClinicalTrials.gov finds many RCTs have been initiated. In the meantime, Slomski reports that 20% of patients with MS in the US and 50% in Europe have serum 25(OH)D levels below 50 nmol/L.
Maintaining optimal vitamin D levels is important. When living in colder environments or spending most of the day indoors, it is important to consume more vitamin D. Few foods are naturally rich in vitamin D. Fortified milk is an important source of vitamin D but one must consume 5-7 cups daily to obtain the recommended daily 15-20 ug vitamin D.
Vitamin D in fortified foods and dietary supplements can be found in two forms: vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). Vitamin D3 is more effective in raising and maintaining serum 25(OH)D.
Follow the science. Choose supplements or foods containing vitamin D3 to maintain serum 25(OH)D levels ≥50 nmol/L.
Slomski A. Vitamin D levels appear to be a robust predictor of MS progression. 2014 JAMA doi 10.1001/jama.2014.1553
Kingwell E, Marriott JJ, Jette N, Pringsheim T, Makhani N, Morrow SA, Fisk JD, Evans C, Beland SG, Kulaga S, Dykeman J, Wolfson C, Koch MW, Marrie RA. Incidence and prevalence of multiple sclerosis in Europe: a systematic review. 2014 BMC Neurology doi: 10.1186/1471-2377-13-128
Ascherio A, Munger KL, Simon KC. Vitamin D and multiple sclerosis. 2010 Lancet Neurol doi: 10.1016/S1474-4422(10)70086-7
Ascherio A, Munger KL, White R, Kochert K, Simon KC, Polman CH, Freedman MS, Hartung H-P, Miller DH, Montalban X, Edan G, Barkhof F, Pleimes D, Radu E-W, Sandbrink R, Kappos L, Pohl C. Vitamin D as an early predictor of multiple sclerosis activity and progression. 2014 JAMA Neurol doi: 10.1001/jamaneurol.2013.5993
Logan VF, Gray AR, Peddle MC, Harper MJ, Houghton LA. Long-term vitamin D3 supplementation is more effective than vitamin D2 in maintaining serum 25-hydroxyvitamin D status over the winter months. 2012 Br J Nutr doi: 10.1017/S0007114512002851
Tripkovic L, Lambert H, Hart K, Smith CP, Bucca G, Penson S, Chope G, Hypponen E, Berry J, Vieth R, Lanham-New S. Comparison of vitamin D2 and vitamin D3 supplementation in raising serum 25-hydroxyvitamin D status: a systematic review and meta-analysis. 2012 Am J Clin Nutr doi:10.3945/ajcn.111.031070