Goitre

This is the most common presentation. Since the deficiency is endemic, goitres tend to occur in those areas. Goitres present as large swellings in the anterior neck. There usually only have cosmetic consequences, but if they a large then can cause compressive symptoms such as recurrent laryngeal nerve compression causing hoarseness of voice. The goitre may also compress the trachea causing airway obstruction.

Hypothyroidism

This is becoming very rare, and happens in individuals with severe deficiency with goitres. The patient presents with typical symptoms such as weight gain, mental slowing, cold intolerance, menorrhagia and mood disorders.

Cretinism

This is the most catastrophic consequences of these deficiency. The affected children suffer from mental retardation, stunted growth and mutism [8].

• Goiter

  […] return to Swine Manual index Hyperplastic thyroid glands (goiter) occasionally occur in swine. [vetmed.iastate.edu]

  The enlargement of the thyroid gland due to dietary iodine deficiency is called endemic goiter. Iodine intakes consistently lower than 50 μg/day usually result in goiter. [ncbi.nlm.nih.gov]

• Fatigue

  Jacob Teitelbaum, MD, is author of the popular free Phone app "Cures A-Z," and of the best-selling books From Fatigued to Fantastic!, The Fatigue and Fibromyalgia Solution, and Pain Free 1-2-3. [prohealth.com]

  Major fatigue. As mentioned above, iodine is important for the body’s energy production. Without enough you may feel fatigued and sleepy. You may also be cranky and experience mood swings. 2. Thyroid disfunction. [organicauthority.com]

  When it is not functioning properly because of the lack of iodine, you may experience some of the following: Weight gain Fatigue Depression Low energy level Heart Disease Anxiety High cholesterol levels Sexual dysfunction Infertility Bowel problems Hair [iodine-resource.com]

  Here are just a few: Fatigue - An underactive thyroid typically causes fatigue. Iodine supplementation can quickly activate the thyroid and relieve fatigue. Dr Abraham reports iodine deficiency may harm pituitary-adrenal function in rodents. [life-enthusiast.com]

  Symptoms include: an intense intolerance to cold temperatures drowsiness followed by extreme fatigue, and ultimately, unconsciousness In people with hypothyroidism, certain things can trigger a myxedema coma. [healthline.com]

• Weight Gain

  An often-overlooked signs of IDD is weight gain. The Underlying Cause of Unexplained Weight Gain Iodine is a mineral that is essential for optimal health. [undergroundhealthreporter.com]

  The symptoms of low hormones, include weight gain, depression and mental slowing. In children born to mothers with iodine deficiency, there are at risk of mental retardation and poor growth. [symptoma.com]

  Weight gain. If you don't burn calories for energy, you store it as fat. Two studies in our research center showed an average 32 1/2 pound weight gain in fibromyalgia. Constipation. It takes energy to keep things moving. Cold intolerance. [prohealth.com]

  Low levels of iodine may cause an underactive thyroid gland and symptoms of hypothyroidism (eg, tiredness, constipation and weight gain). Iodine deficiency in pregnant women may cause problems for the baby, including learning disability. [patient.info]

  In adults, hypothyroidism may cause puffy skin, a hoarse voice, impaired mental function, dry and scaly skin, sparse and coarse hair, intolerance to cold, and weight gain. [msdmanuals.com]

• Disability

  Congenital hypothyroidism due to iodine deficiency is the most common preventable cause of intellectual disabilities in the world. [thyroid.org]

  Iodine deficiency is the most common preventable cause of intellectual disabilities in children. [ncbi.nlm.nih.gov]

  Underactive thyroid gland due to iodine deficiency from birth (congenital hypothyroidism) is the most common preventable cause of severe learning disability in the world. [patient.info]

  Unless affected babies are treated soon after birth, a disorder that causes intellectual disability and short stature (cretinism) develops. Babies with cretinism may be deaf and mute. They may have birth defects and/or hypothyroidism. [msdmanuals.com]

• Falling

  Getty Images When your iodine intake falls below 100 micrograms (mcg) per day, your body starts to pump out more of a thyroid hormone called TSH, according to the National Institutes of Health (NIH). [prevention.com]

  The American Thyroid Association reports: “As the body’s iodine levels fall, hypothyroidism may develop, since iodine is essential for making thyroid hormone. [express.co.uk]

  They found a high burden of iodine deficiency in the general population: 62% of school-age children and 85% of pregnant women fall below the WHO's adequacy range. [sciencedaily.com]

  HYPOTHYROIDISM – As the body’s iodine levels fall, hypothyroidism may develop, since iodine is essential for making thyroid hormone. [thyroid.org]

• Overeating

  Over the years profound improvements in nutritional iodine status in North-eastern Sicily has occurred, due to both silent and active iodine prophylaxis. [ncbi.nlm.nih.gov]

  Many of the pigs have a mucinous edema, especially over enlarged foreparts of the body. The skin in these areas is thick and doughy. The tongue is often edematous and may protrude from the oral cavity. [vetmed.iastate.edu]

• Failure to Thrive

  Babies born to mothers with severe iodine deficiency may have: Mental retardation Slow growth or failure to thrive Hearing and speech impairments Low intelligence Cretinism Short stature Abnormal gait Low iodine results in many of these birth abnormalities [vitamins.lovetoknow.com]

• Metallic Taste

  Symptoms: edgy, irritable, anxious, rash, headache, metallic taste, thyroid pain, palpitations, GI No anaphylaxis Caution Labs: HS CRP > 3, Sed > 20, Fibrinogen > 350 mg/dL, +ANA, elevated Immunoglobulins, HLA B27, methylation defects Hashimoto's Protocal [fullspectrumfamilymed.com]

  Toxic amounts of iodine usually cause an IgD immune response along with toxic symptoms, including: acne, rashes, diarrhea, fever, headache, increased salivation, metallic taste in mouth, nausea, and sneezing. [sott.net]

• Muscle Cramp

  I have experienced the following symptoms which are all deficiency related: Muscle cramps and joint pain Carpal tunnel/tendinitis A feeling of neck swelling/enlargement Hoarse voice or weak voice Dry skin, brittle fingernails Menstrual irregularities [iodine-resource.com]

  A lack of it results in poor athletic performance, undue lactic acid buildup, muscle cramping, difficulty in losing fat, poor recovery, and even twitchy-heart arrythmias. [t-nation.com]

• Skin Lesion

  Very large amounts of iodide may cause a brassy taste in the mouth, increased salivation, GI irritation, and acneiform skin lesions. [merckmanuals.com]

  Topical - Full strength Lugol's prn Great on acne Any skin lesions May cause irritation Pets: One drop Lugol's and a pinch of Celtic salt in their drinking water [fullspectrumfamilymed.com]

  If the contact is short, it may merely irritate and inflame the skin but extended contact can cause skin lesions. Gaseous iodine is also an irritant. [progressivehealth.com]

  The side-effects reported are: an unpleasant brassy taste. increased salivation and sneezing. headache in the frontal sinus. acne-like skin lesions. reduced sex drive / libido. [growyouthful.com]

• Eruptions

  Answer: Iodine Deficiency during pregnancy (1, 2) Iodine deficiency is also linked to higher incidence of AHDH and lower IQ (3), and weak enamels and delayed eruption of teeth (4). [wholehealthdentalcenter.com]

  The headaches and skin eruptions are probably caused by the release of stored toxins. During iodine supplementation, I recommend that you drink more water than usual to help remove the toxins being released. [growyouthful.com]

  Oxygen and hydrogen produced water vapor during the eruptions; as water vapor rose through the atmosphere, it condensed, giving rise to the primordial rainfall. [omicsonline.org]

• Neck Swelling

  Symptoms It usually presents with a swelling in the front of the neck due to an enlarged thyroid gland (goitre). The neck swelling is initially smooth but eventually get nodular with time. [symptoma.com]

  I have experienced the following symptoms which are all deficiency related: Muscle cramps and joint pain Carpal tunnel/tendinitis A feeling of neck swelling/enlargement Hoarse voice or weak voice Dry skin, brittle fingernails Menstrual irregularities [iodine-resource.com]

  Grade 2: A swelling in the neck that is clearly visible when the neck is in a normal position and is consistent with an enlarged thyroid when the neck is palpable. Unique codes were assigned to each participant to ensure confidentiality. [bmcresnotes.biomedcentral.com]

• Headache

  […] decreased fertility rate, increased infant mortality, fibrocystic breast disease, atherosclerosis and breast cancer. (5) Iodine Deficiency Symptoms Clinical signs and symptoms of iodine deficiency include: (6) Depression Difficulty losing weight Dry skin Headaches [eastafro.com]

  […] risk factors for sleep apnea later Dry mouth, which can lead to susceptibility to cavities and gum disease Pain: “Low thyroid is almost a constant finding in Dental Distress Syndrome” (7) Common symptoms of low thyroid include: Fatigue, weight gain, headache [wholehealthdentalcenter.com]

  The side-effects reported are: an unpleasant brassy taste. increased salivation and sneezing. headache in the frontal sinus. acne-like skin lesions. reduced sex drive / libido. [growyouthful.com]

  It has also been associated with: excess mucus production, fatigue, hemorrhoids, headaches, keloid scarring, and migraine headaches. There is an epidemic of obesity and overweight people in this country. And no wonder! [sott.net]

• Stroke

  Published: June, 2011 The surplus of sodium in the American diet contributes to a host of cardiovascular problems, from high blood pressure and stroke to heart attack, heart failure, and more. [health.harvard.edu]

  ‘As soon as you even mention salt in Britain, people start talking about high blood pressure and strokes,’ says Dr Vanderpump. ‘That’s why I think the Government doesn’t want to intervene, because it’s always easier to leave the status quo. [dailymail.co.uk]

  You know that inflammation is closely associated with at least 100 of the greatest human maladies, including heart disease, cancer, stroke, and autoimmune disease. [t-nation.com]

  Samaj Adhikari, Kumar Paudel, Kamal Pandit, Shovit Thapa, Bikram Prasad Gajurel and Khagendra Dahal, Acute renal infarction and cardioembolic stroke in a patient with atrial fibrillation and hyperthyroid-induced cardiomyopathy: a case report, Journal [doi.org]

• Dizziness

  Thyroid UK said symptoms of the condition include weight gain, diarrhoea and dizziness, breathlessness and even loss of libido. Adults need 0.14mg of iodine a day. [express.co.uk]

  If you’re feeling dizzy and suspect you’ve had too much iodine, drink plenty of water to flush out the excess. Choose Mara Seaweed A 2g serving of Mara’s Dulse or Shony is enough to provide your RDI of iodine. For Kombu, only 1g is needed. [maraseaweed.com]

• Apathy

  In the countries of the former USSR, complacency and apathy followed initial success. The cooperation of the salt industry in providing iodized salt of good quality is very important for sustainability. [scielosp.org]

Individual tests are usually rare with most tests being done at community levels. The most common system is to measure iodine concentrations in urine; the deficiency is classified as:

• Mild: 50 to 99mcg/l
• Moderate: 20 to 49 mcg/l
• Severe: < 20mcg/l [9]

• Hot Thyroid Nodule

  I have a history of “hot” thyroid nodules – nodules that spew thyroid hormone without regard for what my body needs, making me hyperthyroid. I had a partial thyroidectomy when I was 19, and most of my thyroid was removed. [sherylcanter.com]

  Markus Eszlinger, Knut Krohn, Jürgen Kratzsch, Carsten Voigt and Ralf Paschke, Growth Factor Expression in Cold and Hot Thyroid Nodules, Thyroid, 11, 2, (125), (2001). R. Gómez de la Torre, J. Otero Díez and S. [doi.org]

Supplementation is the mainstay of treatment, but will not reverse the signs, such as goitre or cretinism, but will correct hypothyroidism. Goitres are usually a cosmetic problem, and if there is no indication only supplementation is indicated. Thyroidectomy will be required if there are compressive symptoms. Some nodules may become semiautonomous once iodine levels are normalized, causing hyperthyroidism.

Unfortunately once the consequences of iodine deficiency set in, supplementation will not reverse it. This is true for goitres and cretinism. A continuous supplementation program is required, to avoid these consequences [7].

The daily requirement for iodine is approximately 52mcg per day (150mcg/day as per World Health Organisation recommendations) in adults with the highest requirements during pregnancy, when they may reach 250mcg/day. Intake of less than 30mcg over a prolonged period will lead to moderate to severe deficiency. Iodine is found in many food naturally, such as fish, some drinking water and from produce grown in iodine rich soil. Mountainous regions have low levels of iodine in the soil and if there are no other sources of iodine, the inhabitants may become deficient [2] [3].

There are over 2.2 billion people who are at risk of iodine deficiency. The clinical disorders tend to be worse in areas with other concomitant deficiencies such as vitamin A. The distribution of the deficiency has no race or gender prediction and is totally geographical. The incidence has significantly reduced since the early 20th century due to mandatory iodine supplementation in salt. In many countries uniodinated salt is very rare [4] [5].

Iodine is easily absorbed in the gut as iodide and then actively taken up by the thyroid gland where it is incorporated to form thyroxine and triiodothyronine. Thyroid hormones are important for regulating metabolism, and are essential in neuronal and sexual development in neonates.

If there is deficiency, the body has a number of mechanisms to try and maintain hormone levels. The pituitary releases more thyroid stimulating hormone, when the levels of thyroxine drop. This stimulates the thyroid follicle cells to take up more iodine from circulation to produce more thyroxine. There is also increased production of triiodothyronine which requires less iodine atoms and is more active (this conserves iodine).

Consequences of deficiency

• Goitre: This is one of the most well-known signs of iodine deficiency. The growth of the goitre is stimulated by the high levels of thyroid stimulating hormone, from the pituitary as a response to low thyroxine level. The chronic stimulation by the stimulating hormone causes follicle cells to proliferate and ultimately increase in the overall size of the goitre. The goitre is initially diffuse but eventually gets nodular with time, due to irregular proliferation.
• Hypothyroidism: This is extremely rare due to supplementation, but when it does occur there is a goitre. 
• Cretinism: This is a catastrophic consequence to a neonate. Thyroxine and iodine are required for maturation and development of the fetus. Children born with this, if not treated, will have mental retardation, and developmental problems [6].

Continuous population based iodine supplementation is recommended by the World Health Organisation which recommends 150mcg/day in nonpregnant individuals. This has been done in most countries with iodization of salt (In many countries, it is mandatory) [10].

Alterations in the levels of iodine, deficiency or excess have consequences on thyroid hormone production. Deficiency may impose a variety of consequences, including goitre, intellectual disability and hypothyroidism [1].

Definition

Iodine deficiency is a condition when there is a poor intake of a necessary element called iodine. Low levels of iodine cause imbalance of a hormone called thyroxine which is required for a number of important functions.

Cause

Iodine is usually found in food like vegetables and fish. In some areas there is poor levels of iodine in the soil and therefore the food in those regions has little iodine.

Symptoms

It usually presents with a swelling in the front of the neck due to an enlarged thyroid gland (goitre). The neck swelling is initially smooth but eventually get nodular with time. It can get to a size that it block the air pipes causing difficulty in breathing. The symptoms of low hormones, include weight gain, depression and mental slowing. In children born to mothers with iodine deficiency, there are at risk of mental retardation and poor growth.

Diagnosis

The diagnosis is usually not difficult as the goitres usually come from regions where there is deficiency. These regions tend to have many goitres. The iodine levels may be obtained from urine tests.

Treatment

Treatment includes adding iodine to food. Most countries add iodine to salt, and if you are found deficient you may be given an injection, but it is normally replaced by mouth. This does not reverse the goitre. The goitres are usually removed only if there are causing breathing problems or voice problems.

1. Walker SP, Wachs TD, Gardner JM, et al. Child development: risk factors for adverse outcomes in developing countries. Lancet 2007; 369:145.
2. WHO Secretariat, Andersson M, de Benoist B, et al. Prevention and control of iodine deficiency in pregnant and lactating women and in children less than 2-years-old: conclusions and recommendations of the Technical Consultation. Public Health Nutr 2007; 10:1606.
3. Zimmermann MB. Iodine deficiency. Endocr Rev 2009; 30:376.
4. ICCIDD, UNICEF, WHO. Assessment of iodine deficiency disorders and monitoring their elimination. Geneva, World Health Organization, 2001
5. Pearce EN, Andersson M, Zimmermann MB. Global iodine nutrition: Where do we stand in 2013?. Thyroid. May 2013;23(5):523-8
6. Zimmermann MB. Iodine requirements and the risks and benefits of correcting iodine deficiency in populations. J Trace Elem Med Biol. 2008;22(2):81-92
7. Zimmermann MB, Wegmuller R, Zeder C, et al. Rapid relapse of thyroid dysfunction and goiter in school-age children after discontinuation of salt iodization. Am J Clin Nutr. Apr 2004;79(4):642-5
8. Cao XY, Jiang XM, Dou ZH, et al. Timing of vulnerability of the brain to iodine deficiency in endemic cretinism. N Engl J Med 1994; 331:1739.
9. Food and Nutrition Board Institute of Medicine. Dietary reference intake. Washington, DC: National Academy Press, 2001.
10. Zimmermann MB, Aeberli I, Torresani T, et al. Increasing the iodine concentration in the Swiss iodized salt program markedly improved iodine status in pregnant women and children: a 5-y prospective national study. Am J Clin Nutr. Aug 2005;82(2):388-92.