In this 2019 analysis, Nuray Çakici et al. review associations between schizophrenia, major depressive disorder (MDD), and a variety of serum analytes. The results of the analysis indicate metabolic dysfunction is common in and shared between schizophrenia and MDD, which may point to shared pathological elements. Future research may be able to further illustrate whether metabolic dysfunction plays a causal role in these disorders, contributes to their progression, or is merely their consequence.