Global Perspectives on China’s Iodine Dietary Reference Intakes: Revisions, Public Health Implications, and Future Strategies

Iodine is an essential trace element for the human body and a fundamental precursor for the synthesis of thyroid hormones, playing a critical role in maintaining thyroid function. Since iodine cannot be synthesized by the body, it must be obtained from external sources. The development of dietary reference intakes for iodine has evolved over time, with various countries establishing guidelines based on local dietary surveys, iodine status assessments, and health outcomes. The dietary reference intakes of iodine vary widely across different regions due to differences in dietary habits, food fortification policies, and iodine supplementation practices. This review primarily synthesizes and analyzes the latest research data on iodine intake reference values set by China and compares these values with those established by other countries and organizations. Additionally, this review examines primary dietary sources of iodine, such as iodized salt, dairy products, and seafood, and discusses challenges posed by public health initiatives like salt-reduction campaigns that may impact overall iodine intake. Furthermore, it highlights current global trends in iodine nutrition while emphasizing countries where iodine intake is classified as sufficient, deficient, or excessive. By comparing iodine intake recommendations worldwide, this review aims to provide a comprehensive understanding of iodine nutrition and its impact on public health. It also identifies gaps in current research and offers insights into future directions for ensuring optimal iodine intake through updated guidelines and public health interventions.