Juncal-Ruiz M, et al. - In a study sample of first-episode psychosis (FEP) patients and healthy volunteers, the impact of body mass index (BMI) on basal serum cytokine levels was assessed. The total sample was separated into two groups: normal-weight and overweight individuals. The overweight group was the one that showed the most differences in the basal serum cytokine levels between patients and healthy volunteers. These data indicate that excess weight can alter the homeostasis of the immune system and therefore may have an additive pro-inflammatory effect on the one produced by psychosis in the central nervous system.