Iodine deficiency and intelligence: Mechanisms of influence and possibilities of prevention

Iodine deficiency remains a global public health issue worldwide and is recognized as one of the leading preventable causes of intellectual impairment. The entire territory of Russia is classified as a region with chronic iodine deficiency. Despite ongoing regional prevention programs, the absence of a federal law on universal salt iodization means that mild iodine deficiency persists. This deficiency not only increases thyroid pathology but also leads to a decline in the intellectual potential of the population. The aim is to summarize available data on the relationship between iodine intake and intelligence quotient (IQ) levels, with a particular focus on critical periods of development (intrauterine and neonatal periods, early childhood). A search for publications was conducted in PubMed, Medline, Google Scholar, and eLIBRARY.ru databases using the keywords: iodine deficiency, intelligence, brain, neurodevelopment, prevention for the last 10 years. Severe iodine deficiency is associated with profound and irreversible neurodevelopmental disorders (Cretinism). Moderate iodine deficiency leads to measurable cognitive impairment in children, while mild deficiency is associated with impairments in attention, memory, academic performance, and decision-making speed. Group-based and individual prevention of iodine deficiency in at-risk populations ensures adequate iodine status and positively influences intellectual outcomes. Iodine deficiency plays a critical role in the formation of cognitive functions, especially during the early stages of neurodevelopment. Prevention in at-risk groups using pharmacological preparations of potassium iodide containing the physiological dose of iodine required during these periods is essential.