<p>Endocrine disruptors (ED) are exogenous substances or mixtures that alter the function(s) of the endocrine system and consequently cause adverse health effects for human beings and their offspring. Human exposure occurs through multiple exposure routes such as ingestion of food and water, inhalation of gases and airborne particles, and dermal absorption, resulting in exposure to complex mixtures of ED. These may have additive or multiplicative effects that can occur even when each chemical is present in the mixture at levels without individual effects. Many ED have been classified as thyroid disruptors, i.e. substances that can interfere with normal thyroid function. Because of the critical role of thyroid hormones during development, exposure to ED during pregnancy, lactation and childhood can have severe effects, as many of these substances are able to cross the placenta and are present in breast milk. The endocrine system has evolved to adapt rapidly to exogenous nutritional, microbial and environmental changes. Therefore, if exposure to ED is transient and at low or moderate doses, these hormonal compensations may be sufficient to counteract the more severe effects of exposure. However, persistent exposure to a mixture of ED at particularly vulnerable life stages may exceed the adaptive capacity of the system and thus cause irreversible changes that may also be transmitted to offspring. In addition, in the presence of even mild iodine deficiency adaptive compensatory mechanisms (e.g., goitre) may fail in long-term increasing the risk of thyroid hypofunction and altering gene expression and eventually causing cancer. However, studies that have analysed the relationship between iodine nutrition and the effects of exposure to ED seem to suggest that an adequate iodine intake can mitigate the negative effects of ED exposure.</p>