A recent study published in the journal Neuroscience Letters has combined data from eleven studies in a systematic review and meta-analysis of vitamin D levels in blood and multiple sclerosis.

Study author Dr Duan, and colleagues at the Department of Neurology, The First Affiliated Hospital, Harbin Medical University, Harbin, China reported that on average MS patients had lower levels of vitamin D (25-hydroxyvitamin D)  compared to healthy controls (weighted mean difference -14.52, 95% CI, -23.83 to -5.22).

Of concern, there was significant heterogeneity between studies with an I2 of 92% (p<0.00001). The authors commented that the ‘heterogeneity may be due to the differences in ethnicity, country, season of blood sampling and age of the participants studied.’

The full study can be accessed here.