The effects of vitamin B on the immune/cytokine network and their involvement in depression

Highlights • Many patients with depression have low levels of vitamin B (B1, B2, B3, B6, B9, B12). • Vitamin B supplementation has been shown to improve depression outcomes. • The immune system plays a fundamental role in maintaining health, and an overactive or underactive immune system leads to diseases. • There is a link between the immune system and depression. People with depression present with a high pro-inflammatory profile. Anti-inflammatory cytokines have been shown to improved depression. • There is a clear link between vitamin B, the immune system and depression.