Exploring potential mechanisms for zinc deficiency to impact in autism spectrum disorder: a narrative review

Autism spectrum disorder (ASD) is a heterogeneous and complex group of life-long neurodevelopmental disorders. How this clinical condition impacts an individual's intellectual, social and emotional capacities, contributing to alterations in the proprioceptive and sensory systems and increasing their selective attitude towards food, is well described in the literature. This complex condition or status exposes individuals with ASD to an increased risk of developing overweight, obesity and non-communicable diseases compared with the neurotypical population. Moreover, individuals with ASD are characterised by higher levels of inflammation, oxidative stress markers and intestinal dysbiosis. All these clinical features may also appear in zinc deficiency (ZD) condition. In fact, zinc is an essential micronutrient for human health, serving as a structural, catalytic and regulatory component in numerous physiological processes. The aim of this narrative review is to explore role of ZD in ASD. Factors affecting zinc absorption, excretion and dietary intake in this vulnerable population are taken into consideration. Starting from this manuscript, the authors encourage future research to investigate the role of ZD in ASD. The perspective is to potentially find another missing piece in the 'ASD clinical puzzle picture' to improve the health status of these individuals.