Iodine deficiency is a widespread problem in western, southern and eastern parts of China, as their iodized salt intake level is much lower than the average national level. Iodine deficiency is a range of disorders that affect many different populations. It is estimated that IDDs affect between 800 million and 2 billion people worldwide; countries have spent millions of dollars in implementing iodized salt as a means to counteract the iodine deficiencies prevalent today. [1] With China accounting for "40% of the total population", [2] it bears a large portion of those who are iodine deficient.
Iodine is a micronutrient the body needs to properly produce thyroid hormones. The human body is not able to produce it, and iodine is an essential nutrient. Iodine is not readily available in many foods, thus making it difficult for many people to obtain it. One particular source, found in great supply, is ocean water although it is not an effective dietary source. Iodine deficiency diseases (IDDs) are able to develop before birth, so it is crucial for all populations to have sufficient levels of the micronutrient and prevent such diseases from developing early on.
The Chinese government implemented a program of regulating salt to contain iodine starting in 1995. A more recent study has confirmed that the availability of iodized salt in the provinces has increased since this date. Today, about one third of the Chinese population is living in areas with low concentrations of iodine in their water supply. [2] Salt is available in China for less than the retail price in some other countries, at about 5 cents, and is consumed regularly in most diets. This is very cost effective for producers who now must abide by the iodized salt regulations and those for those who need to consume it. The black market, however, is laden with the non-iodized counterpart and partially accounts for the population still be fairly saturated with IDDs.
The levels of iodized salt were measured in a urinalysis of households in China. It was confirmed that about 15–25 mg/kg of iodized salt content in the diet was sufficient in preventing IDDs and preventing side effects of over consumption. In provinces where people are consuming less than this amount, there is an increased amount of improper brain development in children. Furthermore, one can see the relation between the importance of iodine in thyroid hormones and the IDD goitre. This disease causes a swelling in the neck, where the thyroid glands are, leading to impaired cognitive abilities. The child population was about 20% saturated with the disease but continues to decrease with the new initiatives. [3]
Another common IDD prevalent in China is Kashin-Beck disease [ citation needed ]. A particular outbreak in Tibet was recorded as occurring from lack of iodine. Kashin-Beck is a bone deformity endemic. Iodine deficiency, hypothyroidism, and low serum concentrations of thyroxine-binding globulin were significantly related to Kashin–Beck disease. [4] Iodine supplemented irrigation water in combination to iodized salt helps in reducing the neonatal and infant mortality rates. The province of Xinjiang suffers severely from IDDs and in 1993, started the use of potassium iodate in combination with irrigation water. [5] Irrigation water is widely used and accessible to all households making it the predominant solution in reducing micronutrient deficiencies for Xinjiang.
Congenital iodine deficiency syndrome (CIDS), also called cretinism, is a medical condition present at birth marked by impaired physical and mental development, due to insufficient thyroid hormone production (hypothyroidism) often caused by insufficient dietary iodine during pregnancy. It is one cause of underactive thyroid function at birth, called congenital hypothyroidism. If untreated, it results in impairment of both physical and mental development. Symptoms may include: goiter, poor length growth in infants, reduced adult stature, thickened skin, hair loss, enlarged tongue, a protruding abdomen, delayed bone maturation and puberty in children, mental deterioration, neurological impairment, impeded ovulation, and infertility in adults.
A goitre, or goiter, is a swelling in the neck resulting from an enlarged thyroid gland. A goitre can be associated with a thyroid that is not functioning properly.
Hyperthyroidism is the condition that occurs due to excessive production of thyroid hormones by the thyroid gland. Thyrotoxicosis is the condition that occurs due to excessive thyroid hormone of any cause and therefore includes hyperthyroidism. Some, however, use the terms interchangeably. Signs and symptoms vary between people and may include irritability, muscle weakness, sleeping problems, a fast heartbeat, heat intolerance, diarrhea, enlargement of the thyroid, hand tremor, and weight loss. Symptoms are typically less severe in the elderly and during pregnancy. An uncommon but life-threatening complication is thyroid storm in which an event such as an infection results in worsening symptoms such as confusion and a high temperature; this often results in death. The opposite is hypothyroidism, when the thyroid gland does not make enough thyroid hormone.
The thyroid, or thyroid gland, is an endocrine gland in vertebrates. In humans, it is a butterfly-shaped gland located in the neck below the Adam's apple. It consists of two connected lobes. The lower two thirds of the lobes are connected by a thin band of tissue called the isthmus. Microscopically, the functional unit of the thyroid gland is the spherical thyroid follicle, lined with follicular cells (thyrocytes), and occasional parafollicular cells that surround a lumen containing colloid.
Hypothyroidism is a disorder of the endocrine system in which the thyroid gland does not produce enough thyroid hormones. It can cause a number of symptoms, such as poor ability to tolerate cold, extreme fatigue, muscle aches, constipation, slow heart rate, depression, and weight gain. Occasionally there may be swelling of the front part of the neck due to goitre. Untreated cases of hypothyroidism during pregnancy can lead to delays in growth and intellectual development in the baby or congenital iodine deficiency syndrome.
Human nutrition deals with the provision of essential nutrients in food that are necessary to support human life and good health. Poor nutrition is a chronic problem often linked to poverty, food security, or a poor understanding of nutritional requirements. Malnutrition and its consequences are large contributors to deaths, physical deformities, and disabilities worldwide. Good nutrition is necessary for children to grow physically and mentally, and for normal human biological development.
Potassium iodide is a chemical compound, medication, and dietary supplement. It is a medication used for treating hyperthyroidism, in radiation emergencies, and for protecting the thyroid gland when certain types of radiopharmaceuticals are used. It is also used for treating skin sporotrichosis and phycomycosis. It is a supplement used by people with low dietary intake of iodine. It is administered orally.
Micronutrients are essential dietary elements required by organisms in varying quantities to regulate physiological functions of cells and organs. Micronutrients support the health of organisms throughout life.
Iodised salt is table salt mixed with a minute amount of various salts of the element iodine. The ingestion of iodine prevents iodine deficiency. Worldwide, iodine deficiency affects about two billion people and is the leading preventable cause of intellectual and developmental disabilities. Deficiency also causes thyroid gland problems, including endemic goitre. In many countries, iodine deficiency is a major public health problem that can be cheaply addressed by purposely adding small amounts of iodine to the sodium chloride salt.
In common usage, salt is a mineral composed primarily of sodium chloride (NaCl). When used in food, especially in granulated form, it is more formally called table salt. In the form of a natural crystalline mineral, salt is also known as rock salt or halite. Salt is essential for life in general, and saltiness is one of the basic human tastes. Salt is one of the oldest and most ubiquitous food seasonings, and is known to uniformly improve the taste perception of food, including otherwise unpalatable food. Salting, brining, and pickling are ancient and important methods of food preservation.
Iodine deficiency is a lack of the trace element iodine, an essential nutrient in the diet. It may result in metabolic problems such as goiter, sometimes as an endemic goiter as well as congenital iodine deficiency syndrome due to untreated congenital hypothyroidism, which results in developmental delays and other health problems. Iodine deficiency is an important global health issue, especially for fertile and pregnant women. It is also a preventable cause of intellectual disability.
Food fortification is the addition of micronutrients to food products. Food enrichment specifically means adding back nutrients lost during food processing, while fortification includes adding nutrients not naturally present. Food manufacturers and governments have used these practices since the 1920s to help prevent nutrient deficiencies in populations. Common nutrient deficiencies in a region often result from local soil conditions or limitations of staple foods. The addition of micronutrients to staples and condiments can prevent large-scale deficiency diseases in these cases.
Kashin–Beck disease (KBD) is a chronic, endemic type of osteochondropathy that is mainly distributed from northeastern to southwestern China, including 15 provinces. As of 2011, Tibet has the highest incidence rate of KBD in China. Southeast Siberia and North Korea are other affected areas. KBD usually involves children ages 5–15. To date, more than a million individuals have had KBD. The symptoms of KBD include joint pain, morning stiffness in the joints, disturbances of flexion and extension in the elbows, enlarged inter-phalangeal joints, and limited motion in many joints of the body. Death of cartilage cells in the growth plate and articular surface is the basic pathologic feature; this can result in growth retardation and secondary osteoarthrosis. Histological diagnosis of KBD is particularly difficult; clinical and radiological examinations have proved to be the best means for identifying KBD. Little is known about the early stages of KBD before the visible appearance of the disease becomes evident in the destruction of the joints.
Selenium deficiency occurs when an organism lacks the required levels of selenium, a critical nutrient in many species. Deficiency, although relatively rare in healthy well-nourished individuals, can have significant negative results, affecting the health of the heart and the nervous system; contributing to depression, anxiety, and dementia; and interfering with reproduction and gestation.
Iodine is an essential trace element in biological systems. It has the distinction of being the heaviest element commonly needed by living organisms as well as the second-heaviest known to be used by any form of life. It is a component of biochemical pathways in organisms from all biological kingdoms, suggesting its fundamental significance throughout the evolutionary history of life.
Selenium is an essential micronutrient for animals, though it is toxic in large doses. In plants, it sometimes occurs in toxic amounts as forage, e.g. locoweed. Selenium is a component of the amino acids selenocysteine and selenomethionine. In humans, selenium is a trace element nutrient that functions as cofactor for glutathione peroxidases and certain forms of thioredoxin reductase. Selenium-containing proteins are produced from inorganic selenium via the intermediacy of selenophosphate (PSeO33−).
The Iodine Global Network describes itself as a "non-profit, non-government organization for the sustainable elimination of iodine deficiency worldwide."
Creswell John Eastman is the Clinical Professor of Medicine at Sydney University Medical School, Principal of the Sydney Thyroid Clinic and Consultant Emeritus to the Westmead Hospital. Eastman is an endocrinologist and has directed or conducted research and public health projects into elimination of iodine deficiency disorders (IDD) in Malaysia, Indonesia, Laos, Cambodia, Thailand, several Pacific Islands, Hong Kong, China and Tibet and Australia. For his work in remote areas of China, he has been dubbed the "man who saved a million brains".
Child health and nutrition in Africa is concerned with the health care of children through adolescents in the various countries of Africa. The right to health and a nutritious and sufficient diet are internationally recognized human rights that are protected by international treaties. Millennium Development Goals (MDGs) 1, 4, 5 and 6 highlight, respectively, how poverty, hunger, child mortality, maternal health, the eradication of HIV/AIDS, malaria, tuberculosis and other diseases are of particular significance in the context of child health.
Gabriella Morreale de Escobar was an Italian-born Spanish chemist who specialised in the thyroid. She and her husband Francisco Escobar del Rey showed that thyroid hormones cross the placenta during pregnancy and are essential for fetal brain development. She established a national newborn screening program for congenital hypothyroidism in Spain and helped to introduce iodised salt to prevent thyroid problems caused by iodine deficiency.