Iodine

Iodine is important for the development and proper function of the thyroid. It helps to metabolise fats, promotes growth, and regulates the production of energy. Iodine is essential for absorption of carbohydrates, skin, hair and nail growth, mental health, cholesterol HDL/LDL balance, proper metabolism, conversion of carotene to vitamin A, and the synthesis of protein by ribosomes. It is absorbed in the intestinal tract and is transported through the bloodstream to the thyroid were it is converted into thyroxin.

FOOD SOURCES

Seafood, especially seaweed, sea salt, asparagus, dulse, garlic, Irish moss, soya and lima beans, mushrooms, spinach, squash, sunflower seeds, turnip greens.

SUPPLEMENTATION

Potassium or sodium iodide, iodised salts, seaweed extracts (e.g. fucasoidin). Elevated serum potassium, myotonia congenita are contra-indications. Consult your health care professional if you have hyperthyroidism, kidney disease, or are using any of the following medications: amiloride, antithyroid medications, lithium, spironolactone, triamterene.

SIGNS OF DEFICIENCY

Goiter (enlarged thyroid gland which may be associated with slow mental reactions), dry hair, hardening of the arteries, obesity, lethargy, intolerance to cold, and during pregnancy and infancy can produce mental and physical retardation. Fibrocystic disease of the breast is linked to iodine deficiency. Lithium carbonate with iodine can lead to hypothyroidism or suppression of the thyroid gland.

SIGNS OF TOXICITY

Irregular heartbeat, confusion, swollen neck or throat, bloody/black/tarry stools, acne, dermatitis. Large doses can cause abdominal pain, headaches, burning sensation in the mouth or throat, nausea, vomiting, diarrhoea, asthma, anaphylactic shock (ingestion of 2g has been fatal). diarrhea, fever, headache, increased salivation, metallic taste, numb extremities, swollen salivary glands, skin rash, sore teeth or gums, general weakness.

DAILY MINIMUM REQUIREMENT

150mcg approx. Possibly up to 200mcg for pregnant and lactating women - consult your doctor before supplementing in this case. Supplementation to higher levels may be needed for a limited duration if increased iodine update is required to prevent absorbtion of radio-iodine (iodine 131 emitted from damaged nuclear reactors).