IL1B and major depressive disorder: Recent findings in humans, specifically in 56 patients with mild to moderate depression, randomly assigned to receive vitamin D (50,000 IU 2 wks−1) or placebo for eight weeks, showed that vitamin D intake significantly increased serum 25(OH)D concentrations, accompanied by improvements in symptom severity, independently of circulating IL-1β, IL-6, and hs-CRP concentrations (Table 6) [124].