Vitamin D and B9 genetic scores linked to neuroticism in healthy adults

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Frontiers in Medicine Published April 24, 2026 Medically reviewed April 24, 2026 DOI ↗ By Dr. Ji-eun Park, MD · Brain, Mind & Pain

Key Takeaway

Consider that genetic vitamin scores show sex-specific links to neuroticism in healthy adults, but causation is not established.

This was a cohort study of 348 healthy unrelated individuals in a nonclinical setting. The study assessed genetic polygenic scores (PGS) for vitamin D (VD) and vitamin B9 (VB9) concentrations and evaluated their association with neuroticism scores.

The main results showed a negative association between VB9-PGS and neuroticism scores in women. In men, there was a positive association between VD-PGS and neuroticism scores. For men, neuroticism scores were not correlated with PGS for neuroticism but were associated with PGS for bipolar disorder type 1 and alcohol use disorders. No effect sizes, absolute numbers, or p-values were reported for these associations.

Safety and tolerability data were not reported, as adverse events, serious adverse events, and discontinuations were not reported. Key limitations include the observational design, which cannot establish causation, and the lack of reported effect sizes, confidence intervals, or follow-up duration.

The practice relevance was not reported. The study aimed to evaluate associations, and results suggest effects of genetic propensity might differ across sexes, but clinical outcomes were not assessed.

Study Details

Study typeCohort

EvidenceLevel 3

PublishedApr 2026

View Original Abstract ↓

IntroductionNeuroticism is a personality domain with prognostic value for physical and mental health. To properly inform public health policy, it is crucial to uncover the mechanisms underlying high neuroticism. Many internal and external factors that affect brain development and functioning and therefore might contribute to the variability of neuroticism remain understudied. Among them, the impact of vitamin sufficiency is of great interest, as it is a modifiable factor. This study aimed to evaluate the associations of neuroticism with vitamin D (VD) and vitamin B9 (VB9) using polygenic scores (PGS) in a nonclinical cohort.MethodsWe analyzed data from 348 healthy unrelated individuals, including neuroticism scores on the Eysenck Personality Inventory, VD-PGS, VB9-PGS and PGS for neuroticism-related traits.ResultsThe analysis controlling for demographic and genetic confounders revealed a negative association between VB9-PGS and neuroticism scores in women and a positive association between VD-PGS and neuroticism scores in men. The highest values of the VD-PGS were observed in men, who scored high on both neuroticism and extraversion. In men, unlike women, neuroticism scores were not correlated with PGS for neuroticism but were associated with PGS for bipolar disorder type 1 and alcohol use disorders.ConclusionThe results suggest that the effects on neuroticism of genetic propensity for suboptimal vitamin D and B9 concentrations might differ across the two sexes. The findings are consistent with the idea of the importance of vitamin B9 for emotional stability in women and indicate the involvement of genetic factors predisposing to higher vitamin D levels in excitability-related components of neuroticism in men.