Here you go Wendy. I had a bit of a search on Web of Knowledge. These are just some of numerous papers that came up with a search “vitamin D” AND “multiple sclerosis” AND “prevention”, published in 2011 or 2012. I haven’t been through the papers to identify which are good and which not so, but they give you a flavour of what’s being said at least (NB one is a study of mice so interesting, but not necessarily the same in humans). I’ve put the most relevant bits in bold. It’s going to be rather tricky (i.e. unethical) to ever do a trial of vitamin supplementation versus placebo in babies so this sort of thing appears to be the best we have so far.
Karen x
Salzer et al. Vitamin D as a protective factor in multiple sclerosis. Neurology 2012;79:2140-2145
Objective: To examine the association between 25-hydroxyvitamin D (25[OH] D) levels and the risk of multiple sclerosis (MS) in blood samples collected prospectively and during gestation.Methods: In this nested case-control study, 2 population-based biobanks with 291,500 samples from 164,000 persons collected since 1975 in the northern half of Sweden were used. We identified prospectively collected blood samples from MS cases (n = 192, controls matched 2: 1) and gestational samples from pregnant mothers where the offspring had later developed MS (n 5 37, control mothers matched 5: 1). 25(OH) D levels were measured using an ELISA, and the risk of MS was analyzed using matched logistic regression.Results: Levels of 25(OH) D > 75 (vs < 75) nmol/L in prospectively collected blood samples were associated with a decreased risk of MS (odds ratio [OR] 0.39, 95% confidence interval [CI] 0.16-0.98). No decrease in MS risk was found in the offspring exposed to gestational 25(OH) D levels >= 75 (vs < 75) nmol/L (OR 1.8, 95% CI 0.53-5.8). The prevalence of 25(OH) D levels >= 75 nmol/L in female controls decreased gradually during 1976-2005 (p trend = 0.005).Conclusion: This study supports the presence of an association between high 25(OH) D levels during the years preceding disease onset and a decreased risk of MS. In the very limited material with samples drawn in early pregnancy, where month-of-birth effects were controlled for, we found no association between gestational 25(OH)D levels and MS risk in the offspring. Decreasing 25(OH) D levels in the population may contribute to explain the increasing MS incidence that is suggested from epidemiologic studies.
Ascherio et al. The initiation and prevention of multiple sclerosis. NATURE REVIEWS NEUROLOGY 2012;8:602-612
Although strong genetic determinants of multiple sclerosis ( MS) exist, the findings of migration studies support a role for environmental factors in this disease. Through rigorous epidemiological investigation, Epstein-Barr virus infection, vitamin D nutrition and cigarette smoking have been identified as likely causal factors in MS. In this Review, the strength of this evidence is discussed, as well as the potential biological mechanisms underlying the associations between MS and environmental, lifestyle and dietary factors. Both vitamin D nutrition and cigarette smoking are modifiable; as such, increasing vitamin D levels and smoking avoidance have the potential to substantially reduce MS risk and influence disease progression. Improving our understanding of the environmental factors involved in MS will lead to new and more-effective approaches to prevent this disease.
Disanto et al. Multiple Sclerosis: Risk Factors and their Interactions. CNS & NEUROLOGICAL DISORDERS-DRUG TARGETS 2012;11:545-555
Multiple sclerosis (MS) is a highly debilitating immune mediated disorder of the central nervous system and represents a substantial burden to the developed world. Despite the recent advances in MS research, which risk factors are implicated and how they contribute to MS pathogenesis is largely unknown. However, in line with older studies investigating the genetic and geographical epidemiology of this complex disease, more recent studies have highlighted how MS arises from a combination of genetic susceptibility and environmental exposures acting from gestation to early adulthood. Vitamin D deficiency, season of birth, Epstein Barr virus infection, and smoking behaviour are strongly implicated and able to influence genetic predisposition to MS. Furthermore, these factors appear to act synergistically and the risk of MS in individuals exposed to more than one factor combines multiplicatively. Current evidence suggests that a large part of MS could be prevented and understanding how and when during life risk factors act will ultimately aid the development of prevention strategies.
Fernandes de Abreu et al. Seasonal, gestational and postnatal influences on multiple sclerosis: the beneficial role of a vitamin D supplementation during early life. Journal of the neurological sciences 2011;311:64-?
There is now strong evidence linking vitamin D, the steroid hormone of sunlight, and Multiple Sclerosis (MS). Two of the most intriguing findings are the season of birth and childhood sun exposure effects. They both suggest that a vitamin D deficiency during these critical imprinting periods is a risk factor for MS. After having confirmed that people born in November are at lower risk of developing MS, we devised a mouse model of prenatal vitamin D deficiency. We observed that adult offspring born to vitamin D deficient mothers, when compared to control offspring, developed a striking milder and delayed experimental autoimmune encephalomyelitis (EAE) and permanently overexpressed the vitamin D receptor. This unexpected finding led us to conjecture that the newborns, after having known an in utero vitamin D-deficient environment, were highly sensitive ex utero to cholecalciferol-containing diet and interpreted the postnatal food as a vitamin D enriched environment. To validate this hypothesis, we devised a mouse model of postnatal vitamin D supplementation. Interestingly, using the same EAE model, we demonstrated that a delayed onset and less severe symptoms were displayed by postnatally vitamin D-supplemented mice. The latter finding is in accordance with previous animal studies demonstrating that a postnatal vitamin D deficiency induced an earlier onset and an increased symptom severity of EAE and epidemiological reports describing the importance of an adequate supply of vitamin D during early life.
Mirzaei et al. Gestational Vitamin D and the Risk of Multiple Sclerosis in Offspring. ANN NEUROL 2011;70:30-40
Objective: Vitamin D may have a protective role in the etiology of multiple sclerosis (MS), but the effect of gestational vitamin D on adult onset MS has not been studied.Methods: In 2001, 35,794 mothers of participants of the Nurses’ Health Study II completed a questionnaire inquiring about their experiences and diet during pregnancy with their nurse daughters. We studied the association of maternal milk intake, maternal dietary vitamin D intake, and predicted maternal serum 25-hydroxyvitamin D (25(OH) D) during pregnancy and their daughters’ risk of developing MS.Results: MS was diagnosed in 199 women. The relative risk of MS was lower among women born to mothers with high milk or vitamin D intake during pregnancy. The multivariate adjusted rate ratio (RR) of MS was 0.62 (95% confidence interval [CI], 0.40-0.95; p trend = 0.001) for nurses whose mothers consumed 2 to 3 glasses of milk per day compared with those whose mothers consumed <3 glasses per month, and 0.57 (95% CI, 0.35-0.91; p trend = 0.002) for nurses with mothers in the highest quintile of dietary vitamin D intake compared with those in the lowest. The predicted 25(OH) D level in the pregnant mothers was also inversely associated with the risk of MS in their daughters. Comparing extreme quintiles, the adjusted RR was 0.59; (95% CI, 0.37-0.92; p trend = 0.002).Interpretation: Higher maternal milk and vitamin D intake during pregnancy may be associated with a lower risk of developing MS in offspring.
Alonso et al. A case-control study of risk factors for multiple sclerosis in Iran. MULTIPLE SCLEROSIS 2011;17:550-555
Background: Numerous studies have assessed risk factors for multiple sclerosis (MS), although none have been conducted previously in Iran.Objective: The objective of this study was to study lifestyle and environmental risk factors of MS in the Iranian population.Methods: A case-control study, including 394 MS cases and 394 matched controls, was conducted in MS clinics in different Iranian cities. Information on lifestyles, environmental exposures, and past medical history was obtained from medical charts and phone interviews.Results: In multivariable analysis, sunlight exposure was associated with a lower risk of MS: the odds ratio (OR) and 95% confidence interval (CI) of MS associated with a 1-h increment in daily sunlight was 0.62 (0.53-0.73). Smoking was associated with MS risk in women (OR: 6.48, 95% CI: 1.46-28.78), but not in men (OR: 0.72, 95% CI: 0.31-1.68) (p = 0.002 for interaction). Finally, past history of common surgical procedures, infectious disorders, or exposure to pets and farm animals was not associated with MS risk.Conclusions: Different modifiable lifestyles, including sunlight exposure and smoking, were associated with lower MS risk in Iran. Interventions aimed at promoting smoking cessation and, more importantly, at increasing exposure to sunlight might contribute to the prevention of MS.