Micronutrient–immune interactions in mood and psychotic disorders: a case–control study of vitamin C, iron, zinc, magnesium, and peripheral blood cell indices

Micronutrients play essential roles in metabolic regulation, neurotransmission, and immune function. Disturbances in elements such as zinc, iron, magnesium, and vitamin C have been linked to cognitive impairment, mood dysregulation, and altered immune responses in psychiatric populations. This study aimed to compare serum levels of vitamin C, iron, magnesium, and zinc in patients with mood and psychotic disorders and healthy controls, and to examine their associations with peripheral immune indices, including neutrophil and lymphocyte counts. In this case-control study, 60 psychiatric patients (mood and psychotic disorders) and 20 healthy controls were recruited from 5 Azar Hospital in Gorgan. Serum micronutrient levels were measured using biochemical methods, and complete blood counts were used to determine neutrophil and lymphocyte percentages. Statistical analyses, including group comparisons and correlation tests, were performed using SPSS version 23. The mean age of participants was 40.87 ± 12.58 years. Serum zinc levels were significantly higher in psychiatric patients compared with healthy controls (P < 0.001), with no significant differences between mood and psychotic disorder groups. Serum iron, magnesium, and vitamin C levels did not differ significantly among the three groups. Correlation analyses revealed significant associations between serum zinc and magnesium (r = 0.286, P = 0.027), zinc and iron (r = 0.366, P = 0.004), and iron with both WBC (r = 0.291, P = 0.024) and neutrophil counts (r = 0.313, P = 0.015). The findings suggest that micronutrient-immune interactions may contribute to the biological profile of mood and psychotic disorders. Although causal relationships cannot be inferred, routine assessment of key micronutrients and immune indices may provide additional insight into the metabolic and inflammatory status of psychiatric patients. Further research is warranted to clarify the mechanistic pathways linking micronutrient balance, immune function, and psychiatric symptomatology.