Iodine is regarded as one of the most important trace minerals for human health and it plays a vital biochemical function in the regulation of hormone levels in the body. Iodine is essential in the bio-synthesis of the hormone thyroxine, also known as the thyroid hormone, which regulates metabolism.
Why We Need Iodine
The World Health Organisation has recognised that iodine deficiency is the world’s greatest single cause of preventable mental retardation. Approximately one-third of the world’s population lives in iodine deficient areas and up to 72% of the world’s inhabitants is affected by an iodine deficiency disorder.
Although the glandular system uses iodine in a concentrated way, every cell in the body contains and utilises iodine. Large amounts are also found in the salivary glands, the brain and cerebrospinal fluid, gastric mucosa, breasts, ovaries and some parts of the eye.
Iodine is not only necessary for the production of the thyroid hormone, but it’s also responsible for the production of all the other hormones in the body. Iodine is essential for the normal physical growth and intellectual development of children. It is now thought that a lack of iodine can contribute to the development of certain types of cancer, especially those involving estrogens. Iodine contains potent antibacterial, antiparasitic, antiviral and anti-cancer properties.
An iodine deficiency is often compensated for in the human body, by a sudden increase in the secretion of thyroxine hormone. This sudden increase in the secretion of thyroid hormone can cause the gland to become enlarged and swollen, it can become congested and results in the condition called goiter, a disorder typically seen in individuals affected by a deficient intake of iodine. Physical and mental retardation, also known as cretinism can affect a developing fetus, if the mother’s diet is lacking sufficient iodine.
There are many diseases that can affect the functioning of the thyroid gland, which is centrally important in maintaining overall health. The thyroid gland is formed by two large lobes lying at the base of the throat, which release many hormones necessary for the proper functioning of the body. A condition or disease known as ‘hyperthyroidism’ can start affecting a person if the thyroid gland produces too much thyroid hormone. In this condition, the body’s metabolic rate runs too fast and metabolism is too fast, like a car with an overheated engine.
The secretion of too little of the thyroid hormone will lead to the opposite, a disorder known as ‘hypothyroidism’. This disorder is characterized by sluggish metabolism in the body. The appearance of the symptoms in both of these conditions may be mistaken for the signs signaling a long-term mild depression.
The prevalence of thyroid diseases, and failure to handle them correctly is a modern health issue. Good health and nutrition professionals fully understand the entire process of iodine utilisation by the body, and will be willing to test how the body performs at each stage, realising that each person is unique (one size does not fit all).
Having enough iodine in our diets is the first step in the resolution of many health issues. The RDI (recommended daily intake) of iodine for an adult is roughly 0.15 mg daily. This is a maintenance dose and a guideline only – there is a lot of controversy on this subject, and each person’s body is unique.
Hormone production from iodine can be impaired by various issues such as radiation damage, mercury toxicity, Selenium and Zinc deficiencies, as well as the presence of unbalanced levels of copper. Even if the hormones are produced correctly, the body may show ‘Thyroid resistance’, which is the inability of the cells to accept & utilise the thyroid hormone. Given individual body chemistry, toxicities, deficiencies and diets (because some vegetables are thyroid inhibitors), professional support is recommended to develop a personalized plan if you suspect an imbalance.
What Are the Best Natural Sources of Iodine?
In many industrialised countries, salt has been iodised to prevent the prevalence of goiter. Although, goiter has reduced, this solution not an adequate supply the body’s need for iodine.
Iodine is a relatively rare element, ranking 62nd in abundance among the elements of earth, so unlike other vitamins and minerals, iodine is not present in adequate amounts, in most foods. Some plants absorb iodine when it is present in the soil, but Iodine is primarily found in seawater and rocks near the ocean. Iodine is abundant in all seafood, but seaweeds have the unique ability to concentrate iodine from the ocean, with certain types of brown seaweed accumulating over 30,000 times the iodine concentration of seawater. That is why seaweeds are said to be the best source of iodine in nature.
The iodine level in seaweed is dependent on the type of seaweed. Kelp has the highest amount of iodine, with some kelp species having 8165 mcg/gm. Most Kelp has about 2500 mcg/gm. Other common seaweeds are much lower such as Nori (120 mcg/gm), Wakame (350 mcg/gm), Dulse (925 mcg/gm), Sea Spaghetti (330 mcg/gm), and Sea Lettuce (68 mcg/gm).
Note: Iodine is naturally occuring in seaweeds. Pay attention to the serving suggestions on each pack as excessive consumption may cause harm.
Iodine supplements administered in excess have often induced cases of thyroid toxicity – known as thyrotoxicosis. Symptoms may include fatigue, heat intolerance, hyperactivity, hypertension, nervousness, palpitations, tremor, weakness, menstrual disturbance, exaggerated hair loss, inability to sleep. When eaten as a whole food, not taken as a supplement, research has indicated the presence of other compounds in raw seaweed can promote better utilisation/neutralisation of possible excess than if the iodine element is taken in isolation.
If you are experiencing these symptoms, stop consumption of iodine rich foods and consult a health practitioner for professional advice.
“Iodine: Why You Need It”; Dr David Brownstein; 2007
Health Salon: Iodine for Greatest Mental and Physical — Dr Abraham and Dr Flechas
Your Entire Body, Not Just Your Thyroid, Needs Iodine – Mercola
Assessment of Japanese iodine intake based on seaweed consumption in Japan
Dr Wilson’s articles on Thyroid health
Mercola – iodine deficiency
Disclaimer: This material is provided for educational purposes only and IS NOT intended as a substitute for professional medical advice, diagnosis, or treatment. This information is generic and may not include the latest research. Please do your own research and discuss your findings with a qualified health practitioner who can help you validate the outcomes in the context of your specific & individual health situation.