Iodine is one of the essential microminerals needed by the human body. It is an indispensable component in the production of thyroid hormones. However, low levels of these thyroid hormones in the blood could lead to iodine deficiency that may adversely affect the body’s normal growth and development. This resulting disease state manifests an array of functional and developmental abnormalities, collectively referred as Iodine Deficiency Disorders or IDD. IDD are known to be a significant public health problem throughout much of the world.
According to World Health Organization (2006), the spectrum of disorders caused due to iodine deficiency profoundly affects the quality of human life as it affects all the stages of life, from fetus to adulthood. Below are some of the known health effects of IDD throughout the different human life stages:
Pregnancy and Fetal Stage
Thyroid hormone Thyroxine (T4) plays an important biological role in the growth, differentiation, and maturation of different organs of the body, particularly the brain during the early fetal stage of life. If a diet of a pregnant woman lacks iodine, the developing fetus cannot produce enough thyroxine resulting in hindered fetal growth and mental retardation. The hampered metabolic activities of all the cells consequently lead to irreversible alterations in brain development varying from mild intellectual blunting to cretinism. In areas of severe iodine deficiency, risks of abortion, stillbirths, and some degree of congenital abnormalities are very common.
Neonate and Childhood Stage
The damage to the developing brain that progresses during the neonatal and childhood stages of development can lead to hypothyroid children and cretins. The latter is characterized by severe and irreversible mental retardation, short stature, deaf-mutism, spastic diplegia, and squints. Clinical manifestations of cretinism come in two types, neurological and myxedematous. Both present neurological retardations, however, the latter also suffer from myxedema and dwarfism due to the continuing hypothyroidism. On the other hand, hypothyroid children are intellectually subnormal with physical impairment. Studies have documented that in areas with an incidence of mild to moderate IDD, IQs of school children are less than average compared to those children without IDD.
Adolescent Stage
An adolescent individual with IDD may suffer from juvenile hypothyroidism, retarded physical development, and impaired mental function. The continued adequate supply of thyroid hormones may result in individuals that have low immunity to fight diseases, slow learner, poor work performance, or reproductive problems.
Adulthood. In areas of severe iodine deficiency, many adults suffer from apathy, poor mental function and endemic goiter. They present varying degrees of hypothyroidism and some with complications related to hypometabolic states. Thus, it has been observed that adult individuals with IDD negatively impact economic productivity due to reduced work capacity and impaired mental functions.
Indeed, the health consequences of iodine deficiency disorders affects a wide spectrum of human life stages. Yet, with the increasing awareness of IDD and strategies like iodine supplementation, fortification, and enforced ASIN law, eliminating iodine deficiency disorder is possibly within reach.
/BJC
References:
Kapil, U. (2007). Health Consequences of Iodine Deficiency. Sultan Qaboos Univ Med J. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3074887/
World Health Organization (WHO). (2006). Vitamin and Mineral Nutrition Information System (VMNIS), WHO Global Database on Iodine Deficiency, WHO Press.
World Health Organization (WHO). (2001). Assessment of iodine deficiency disorders and monitoring their elimination: A guide for programme managers.
