iodinesufficient

Iodinesufficient is a nutritional state in which iodine intake meets physiological needs for thyroid hormone synthesis and normal development, preventing iodine deficiency disorders (IDD). At the population level, sufficiency is inferred from measurements of iodine status, most commonly urinary iodine concentration, rather than from assessments of a single individual.

Key dietary sources include iodized salt, dairy products, seafood, eggs, and certain grains. Public health programs often aim to achieve iodine sufficiency through universal salt iodization and surveillance of iodine status. Factors such as geographic iodine content in soil, food choices, and the use of salt substitutes influence sufficiency.

Adequate iodine supports production of the thyroid hormones T4 and T3, which regulate metabolism, growth, and brain development. In pregnancy, iodine sufficiency is particularly important for fetal neurodevelopment. Inadequate iodine can lead to goiter, hypothyroidism, cretinism, and cognitive impairment; excess intake can also disrupt thyroid function in some individuals.

Assessment is typically done with population surveys; the median urinary iodine concentration (MUIC) is the standard indicator. For school-age children, MUIC of 100–199 µg/L is considered adequate; 200–299 µg/L more than adequate; ≥300 µg/L may indicate excess. Pregnant women have a higher adequacy target, commonly 150–249 µg/L. Monitoring supports policy decisions on iodization and supplementation.

See also iodine deficiency disorders, iodized salt, thyroid function.