Vitamin D

 Vitamin D : Recently, a landmark study published in The Lancet Psychiatry has revealed a strong association between neonatal vitamin D levels and the risk of neurodevelopmental disorders.

oBased on a comprehensive Danish dataset of nearly 89,000 individuals, the study highlights that vitamin D deficiency at birth may impact not only bone health but also brain development, an insight with significant implications for countries like India.

• Key Highlights : Higher neonatal vitamin D levels were linked to lower risks of: Schizophrenia (18% lower risk), ADHD (11% lower risk) and Autism Spectrum Disorder (7% lower risk)

o Methods to Test Causality

ü Polygenic Risk Score (PRS): Individuals with genetic predisposition for higher vitamin D had lower risk of neurodevelopmental disorders. Helped rule out reverse causation (i.e., mental illness causing low vitamin D).

ü Mendelian Randomisation (MR): Used genetic variants linked to vitamin D to suggest causal relationship with lower risk of ADHD, schizophrenia, and possibly autism. Limitations due to pleiotropy and genetic overlap acknowledged.

• Relevance for India: AIIMS Rishikesh study: 74% of infants and 85.5% of mothers were vitamin D deficient

o Bengaluru study: 92.1% of newborns had deficiency

o Bundelkhand study: Strong correlation between maternal and infant vitamin D levels