In comparison to depressed non-suicidal patients and healthy controls, patients with suicide attempts had significantly lower mean vitamin D levels. Clinically, 58% of the suicide attempters had vitamin D deficiency. Increased levels of IL-6 and IL-1β in the blood were associated with low vitamin D.A deficiency in vitamin D was found in suicide attempters. The results suggest this deficiency might contribute to higher proinflammatory cytokines previously found in suicidal individuals. The gene discussed is IL1B; the disease is vitamin D deficiency.