If there’s a trace mineral that I’m very fond of, its iodine. Most people think of goitre when you say iodine, with frightening images of swollen necks coming to mind resulting from an enlarged thyroid gland, and that’s where they leave it. Perhaps they’ll go one step further and link iodine with thyroid issues and middle-aged women, but that tends to be the extent of it. Let me start by saying that iodine influences an enormous number of functions in the body and the “health impact” that an iodine deficiency can have on any man, woman and child can be profound.
When you read about the thyroid, you read about iodine. This mineral is an essential element that the thyroid utilizes to make thyroid hormones. Without iodine, the thyroid can’t make thyroid hormones. It’s not just the thyroid gland however, all the glands in the body need iodine that includes the thyroid, ovaries, uterus, breast, prostate, and pancreas. These glands all make hormones, prostaglandins, and other things. There’s not a hormone in the body that can be produced without iodine! Further to that, every cell in the body needs iodine. Whether your male or female, your cells depend upon iodine.
From my own personal and clinical experience, I believe the power of iodine is largely underrated. In fact, most people are very cautious about iodine because of what they’ve read or heard, most of which has been echoed for a very long time and may not reflect the latest research nor the demands of our modern living. Sadly, many people across the world are on thyroid medication and tend to remain on it, for years. Very few of these people are encouraged to look at the root cause of their thyroid issues. Important questions to ask are: “What’s behind their thyroid issue. “Why don’t doctor’s test men? Why are we seeing so much thyroid disruption?”
Ask yourself – “Could my previous understanding about iodine be outdated?
While we’re at it – Why is Hashimoto’s so common today, in comparison to 30, 40 years ago?
Why have we had significant increases in pancreatic, ovarian, and uterine cancers?
More and more health experts believe that iodine deficiency plays a big role in all these health issues.
Really? Can iodine be that important?
With this blog and the next – What Role Do Halides, Perchlorates and other Chemicals Play in Iodine Deficiency, Thyroid Disorders, Fertility Issues and Cancer?, we will dive deep into the essential role that iodine plays in human health.
So Why is Iodine so Important?
Iodine is one of the 50+ nutrients that we need every day to be healthy. It’s an essential mineral just as iron, magnesium and zinc are, meaning that the body cannot produce them, and without them, we can experience an array of health issues or become seriously ill. Iodine is a trace mineral also known as a micro mineral, as the human body only needs these in much smaller amounts, although that doesn’t mean that they are any less important. For a quick refresher on how minerals work, and what are the 5 major essential minerals versus the essential trace minerals click here to read our blog: Are You Getting the “Essential Minerals and Trace Minerals” That Your Body Absolutely Needs?
As you now know, iodine is needed to produce thyroid hormones which are created in the thyroid gland. Our thyroid function is mainly regulated by thyroid-stimulating hormone (TSH) and its job is to control thyroid hormone secretion and keep it in the Goldie Locks zone; not too little, not too much. Iodine is an essential component of the thyroid hormones. In the thyroid gland, iodine combines with the amino acid tyrosine to form the thyroid hormones T4 (thyroxine) and T3 (triiodothyronine), T3 is the active form.
The thyroid gland is a butterfly-shaped endocrine gland that is normally located in the lower front of the neck. The thyroid’s job is to make thyroid hormones, which are secreted into the blood and then carried to every tissue in the body.
The Role of Thyroid Hormones: 1, 2
- Energy creation, helping the body use energy to produce hormones that maintain our metabolism or metabolic rate
- Helps us stay warm and regulates our body temperature
- Controls physical growth
- Allows for proper functioning of the brain, cerebral spinal fluid, heart, liver, kidneys, muscles, and digestive organs
- Supports healthy brain function throughout life, especially during pregnancy and childhood
- Helps govern neurotransmitter production and function, and therefore supports our overall mood and mental health
- Maintains healthy levels of hormones – testosterone levels for example, as well as oestrogen production
- Governs healthy ovarian function, playing a role in helping to ease some of the symptoms of premenstrual tension
- Imperative in for reproductive health, maintaining pregnancy, and our baby’s overall growth and health
- Helps with repair processes in the body, important for healthy skin, muscle repair. Helps us recover from chronic stress, post-traumatic stress, or surgery.
- Maintains healthy breast tissue
- Boosts the immune system and helps to eliminate germs and viruses
- Helps to prevent cancers
- Helps to remove toxic chemicals
Who’s At Risk Of An Iodine Deficiency?
It’s thought that most people in the Western world get enough iodine in their diet, and that severe iodine deficiency is still only a major nutritional deficiency concern in some parts of the world where the iodine content of soil varies geographically. This includes South Asia, Southeast Asia, the Middle East, New Zealand, and European countries. 1,3,4
The iodine content of food therefore from around is therefore inconsistent and unreliable for the most part.
Interestingly although table salt has been iodized since 1924, iodine deficiency is rising again in the Western world. 1,6 According to the World Health Organization at least 40 percent of the world’s population is now at risk for iodine deficiency 5, a fourfold increase over the past 40 years. 4
A good question to ask at this point is, “Why is iodine deficiency rising?”
Thyroid hormones are crucial for many integral functions in the body so it is important to consider if we may be at risk of a deficiency that may be affecting our health to some degree, irrespective of where we live. Especially since iodine deficiency is the most common cause of preventable neuro-developmental delays in the world 3, 4 and is suggested to be the number one cause of preventable mental disabilities in the world.
Ten Potential Risk Factors for Iodine Deficiency Today:
1.Living in a Region of the World that has Low Levels of Iodine in their Soil. 3
2. Having a Low Intake of Dietary Iodine.6
3. Having Low Dietary Intake of Selenium. The thyroid gland has one of the highest concentrations of selenium in the body. Selenium is also necessary for the conversion of the thyroid hormone thyroxine (T4) into its more active counterpart triiodothyronine (T3), and as such a deficiency can cause symptoms of hypothyroidism, including extreme fatigue, mental slowing, goitre, cretinism, and recurrent miscarriage.7
4. Women who are Pregnant or Breastfeeding. Women who are pregnant need about 50% more iodine than other women to provide enough iodine for their baby. Inadequate iodine can result in problems with pregnancy such as miscarriage, stillbirth and brain and nerve damage to the developing foetus. Surveys show that many pregnant women may not get quite enough iodine. 6
5. Smokers or those Exposed to Passive Smoke. Tobacco smoke contains a compound called thiocyanate. The inhibitory effects of thiocyanate on the uptake of iodine are through competitive inhibition of the iodide transport mechanism and may be responsible for the reduction of levels. Other substances in tobacco smoke that can impair thyroid function are hydroxy pyridine metabolites, nicotine and benzapyrenes. Tobacco smoke not only influences thyroid function but can also block thyroid hormone action.8 Is it time to give up cigarette smoking or that vape?
6. Increased Intake/plasma levels of Goitrogens. These substances interfere with the way the body uses iodine. 1, 9 They are present in some plant foods including: soy, and cruciferous vegetables such as cabbage, broccoli, cauliflower, and brussels sprouts. For most people who get adequate amounts of iodine, eating reasonable amounts of foods containing goitrogens is not a concern.
7. People who follow a Vegetarian or Vegan diet. People who follow a vegan diet or who eat few or no dairy products, seafood, and eggs are at risk. 1,10 Seafood, eggs, milk, and milk products are among the best sources of iodine. People who don’t eat much of these foods or don’t eat them at all, might not get enough iodine.
8. Those with Frequent Exposure to Fluoride, Bromine, and Chlorine. Which is most of us unfortunately! I will discuss this in the blog What Role Do Halides Potentially Play in Iodine Deficiency and Thyroid Disorders? but essentially elemental iodine falls within the halogen group on the periodic table of elements. The halogen group also includes chlorine, fluorine, and bromine. These halogens are taken up by the thyroid, since they are chemically similar, preventing iodine from entering thyroid cells.11 The effect is known as competitive inhibition.
Chlorine is used to disinfect pool water, it is the primary ingredient in bleach and is used in many cleaning products for its corrosive properties including toilet bowl cleaners, mildew removers and laundry detergent. Chlorine is also found in city water to manage bacterial growth and to kill disease-causing pathogens. Fluoride is also commonly added to public water supplies while brominated flame retardants (polybrominated diphenyl ethers; PBDEs) are used in countless consumer items such as phones, computers, mattresses, carpets, curtains, clothing, and automobiles. In fact bromine is a chemical compound frequently used in flame retardants, baking ingredients, cell phones, plastic, dye, soda, in pesticides and prescription drugs.
In the past, iodine was used in bread dough conditioners, but due to the lower cost of bromide and that iodine was thought to interfere with the thyroid gland, bromide became the preferred conditioner. Bromide is used as an antibacterial agent along with chlorine in hot tubs and pools. From all accounts it seems that over the last few decades we have become over-chlorinated, over-fluorinated, and over-brominated, all the while becoming deficient in iodine.
A very large population-based study in 2018 examined the impact of chronic low-level fluoride exposure on thyroid function, while considering iodine status. The objective of this study was to determine whether urinary iodine status modifies the effect of fluoride exposure on thyroid stimulating hormone (TSH) levels. Or more simply – does an individual’s iodine status and their exposure to fluoride, impact the function of their thyroid. The weighted sample represented 6,914,124 adults in Canada aged 18-79 who were not taking any thyroid-related medication and urinary fluoride concentrations were measured in spot samples. Conclusions drawn from this study were that adults living in Canada who have moderate-to-severe iodine deficiencies and higher levels of urinary fluoride, may be at an increased risk for underactive thyroid gland activity.12 I discuss the individual health impact of chronic exposure to these chemicals in a separate blog, the important point here is that these other halogens kick iodine out of the body.
9. Those Frequently Exposed to Perchlorates, Thiocyanates, and Nitrates. Perchlorate can occur naturally, but it is also a man-made type of chemical which is used extensively in the manufacture of flares, fireworks, explosives and especially in rocket fuel. It is also often commonly present in various bleaches, fertilizers, batteries and even airbags.
A perchlorate is a chemical compound containing the perchlorate ion, ClO−4. The majority are commercially produced salts mainly used for propellants. Reports show an extremely high concentration of perchlorate particulates around airports. Perchlorates have been found to have leached into the ground water supply from military facilities and the aerospace industry. They are now found in the food supply, with some studies showing that when lettuce was tested in southern California, 83% of the samples showed significant levels of perchlorate.44
Perchlorates, nitrates, and thiocyanates are chemicals that can have an impact on thyroid hormone levels by causing iodide uptake inhibition. 13 At high doses, perchlorate, thiocyanate, and nitrate have been shown to inhibit iodine uptake into the thyroid and decrease thyroid hormone production. All three chemicals are ubiquitous in the environment, and exposures can occur through diet (for example, milk, cruciferous, and leafy vegetables) and drinking water. For more information on perchlorates, nitrates, and thiocyanates click here.46
Exposure to these chemicals may also occur because of the impact humans have on nature. We have seen that perchlorate is used for rockets, missiles, and fireworks. Thiocyanate is found in vegetables and other foods and is a metabolic component of cigarette smoke. While nitrate is a preservative that can be added to food such as fish and meat, and is used as fertilizer.47 Both perchlorate and nitrate are also found in drinking water. Hence, assessing the effects of cumulative exposure to these chemicals that can cause the inhibition of iodine, is of public health interest.Studies suggest that combined exposure to perchlorate, thiocyanate, and low iodine markedly reduces thyroxine production and highlights the potential importance of examining the combined effects of multiple agents when evaluating the toxicity of thyroid-disrupting agents. Researchers concluded that people who have all three factors at the same time have substantially lower thyroid hormone levels than people who do not, and the effect of this combined exposure is substantially larger than the effects seen in analyses focused on only one factor at a time.48
10. Those with Frequent Exposure to Radiation. Nuclear accidents can release radioactive iodine into the environment, increasing the risk of thyroid cancer in people who are exposed to the radioactive iodine, especially children. People with iodine deficiency who are exposed to radioactive iodine are especially at risk of developing thyroid cancer. The U.S. Food and Drug Administration has approved potassium iodide as a thyroid-blocking agent to reduce the risk of thyroid cancer in radiation emergencies.1,3
A Word on Selenium
When selenium levels are low, the thyroid will work harder to produce thyroid hormones, and the body will have a difficult time changing these hormones into forms utilized by cells. It’s important to treat both deficits to re-establish normal thyroid health. A deficiency in selenium will also lead to increased oxidative stress on the thyroid because of reduced glutathione peroxidase enzyme activity, for which selenium is an integral component. Oxidative stress damages our cells. Please see our blog.
It is also worth noting that selenium is hard to get from the plants in our diet as selenium levels in soil are now very low, so a supplement may be indicated. Selenium food sources include; meat, fish, shellfish, liver, kidney, broccoli, brazil nuts, onions and eggs, Shiitake and white button mushrooms, chia seeds, brown rice, seeds (sunflower, sesame, and flax.)
The History of Iodine
If you’d like to read about the history of iodine please click here.
Iodine was discovered in 1811 by a scientist who was experimenting with seaweed and burning the ash when he developed iodine. In 1829, there was a French physician, Dr. Lugol, who created Lugol’s solution and anybody that knows about iodine is familiar with Lugol’s solution. He discovered that bonding iodine to a potassium molecule made it water-soluble and unlocked its antiseptic qualities (more on this later). Then in 1860, a Swiss physician that found that iodine could be used to treat goitre.14
Switzerland and the U.S. were the first countries to iodize salt. At the time, deficiencies in iodine were increasing, iodizing salt made a significant difference in lowering iodine deficiency.14 Since 1924, table salt has been iodized, which means iodine is artificially added to sodium chloride. Although salt is still iodized, the U.S. government noticed a decline in American iodine levels between 1971-1974 and 1988–1994, which they linked to lowered dietary intake of iodine likely due to dietary changes. Less iodine in milk and dairy products, might be one factor for this decline.15
Signs and Symptoms of Iodine Deficiencies:
The American Thyroid Association outlines these three main areas relating to deficiency, yet you’ll see below there are many early signs of iodine deficiency, that can have a significant impact on your health when overlooked.
1.GOITRE – Without adequate iodine, the thyroid progressively enlarges (develops a goitre) as it tries to keep up with demand for thyroid hormone production. Worldwide, iodine deficiency is the most common cause of thyroid enlargement and goitre. Within a goitre, nodules can develop. Patients with a large goitre may experience symptoms of choking, especially when lying down, and difficulty swallowing and breathing.
2. HYPOTHYROIDISM– As the body’s iodine levels fall, hypothyroidism may develop, since iodine is essential for making thyroid hormone. Iodine deficiency is the most common cause of hypothyroidism worldwide. People with hypothyroidism usually have weight gain, which can also lead to sluggish feelings, brain fog, and low energy. Pregnant women with hypothyroidism have water retention, leading to puffy, swollen skin. For more information click here.
Where iodine-rich foods are widely available, the most common cause of primary hypothyroidism is autoimmune thyroiditis, an inflammation of the thyroid gland. Autoimmune thyroid diseases include Graves’ Disease and Hashimoto Thyroiditis, among others. Secondary hypothyroidism refers to an underactive thyroid caused when the pituitary gland fails to signal thyroid hormone production through the release of thyroid-stimulating hormone (TSH).16
While genetic factors, congenital disabilities, autoimmune disorders such as Hashimoto’s disease, thyroid surgery, radiation treatment, pregnancy, or the long-term use of certain medications can also cause hypothyroidism, iodine deficiency however, is the most common cause throughout the world.17
3. FEMALE and PREGNANCY-RELATED PROBLEMS– Iodine deficiency is especially important in women who are pregnant or nursing their infants. Severe iodine deficiency may result in greater oxidative stress in the mother. Greater oxidative stress is a reduction in the body’s ability to break down free radicals, associated with miscarriages, and polycystic ovary syndrome (PCOS), pre-eclampsia, gestational diabetes mellitus, preterm delivery, stillbirth, and congenital abnormalities in their babies.18
Children of mothers with severe iodine deficiency during pregnancy can have intellectual disabilities and problems with growth, hearing, and speech. In the most severe form, an underactive thyroid can result in cretinism (a syndrome characterized by permanent brain damage, deaf mutism, spasticity, and short stature), although this has become rare worldwide.
Iodine deficiency is the most common preventable cause of intellectual disabilities in the world. 19 Even mild iodine deficiency during pregnancy may be associated with low intelligence in children. Delays in language skills, motor skills, low IQ and cases of ADHD and autism, are also linked to iodine deficiency in mothers during pregnancy. 20 More on this in a moment.
A Word on “Periods.”
Our periods are supposed to just turn up. No pain, no cramps, no clots, no tender breasts, no mood swings. Anything else that occurs is just feedback from the body. Feedback asking women to make some different choices about how they eat, drink, move, think, breathe, believe and/or perceive. And it is feedback that they want to act on and yes you guessed it – iodine plays a role.
Symptoms experienced with the menstrual cycle typically involve too much oestrogen and not enough progesterone, or, for more and more women, both. In both situation’s oestrogen is in excess—or oestrogen dominance as it is often referred to. If you are ovulating and your luteal-phase progesterone level is low then you will typically feel highly anxious, have a low mood, and feel like you can’t get your breath past your heart in the lead-up to menstruation. You may also have premenstrual spotting, heavy bleeding, and PMT. If you have low progesterone, then you will need to increase it to feel better. To do that, the focus needs to be on supporting the health of the ovarian follicles themselves. Getting optimal amounts of the nutrients that the ovaries need to correct functioning is essential. These include iodine, selenium, zinc, and magnesium. Interesting hey?.
Early Signs of Iodine Deficiency: 14, 19,21 |
|
Those with iodine deficiency may experience some or many of the following. | |
– Anxiety and depression | – Impaired kidney function |
– Atherosclerosis | – Increased infant mortality |
– Breast cancer | – Lethargy or fatigue |
– Breast heaviness and issues with menopause | – Memory problems and brain fog |
– Constipation and poor gut health | – Menstrual problems |
– Decreased fertility rate | – Muscle weakness and joint stiffness |
– Difficulty losing weight | – Puffy face |
– Dry skin and thinning hair | – Recurring infections |
– Fibrocystic breast disease | – Sensitivity to cold and cold hands and feet |
– Headaches | – Shortness of breath |
– High or increased cholesterol levels | – Swelling of the neck |
– Hoarseness | – Thinning hair |
What is Hyperthyroidism?
If you’d like to read about hyperthyroidism, please click here.
An overactive thyroid causes hyperthyroidism. With this condition, the thyroid releases excess thyroxine (T4), leading to a metabolic imbalance, weight loss, fatigue, and nervousness. While the incidence of hypothyroidism has reached epic proportions, hyperthyroidism appears to effect less than two percent of the U.S. population has this condition. 25
Women are 2 to 10 times more likely to develop hyperthyroidism than men13 and individuals over the age of 60 are also at increased risk (13). People with type I diabetes, adrenal insufficiency, thyroiditis, ovarian or testicular cancer, a family history of thyroid disease, or pernicious anaemia due to a deficiency or malabsorption of vitamin B12 are more likely to develop hyperthyroidism. 13
Because thyroxine regulates metabolism and how the body uses energy in virtually every cell in the body, early symptoms include fatigue, nervousness, increased appetite, irregular or rapid heartbeat, difficulty sleeping, mood swings, trembling, muscle weakness, and unexplained weight loss.22 Other symptoms of an overactive thyroid include:
- Goiter
- Menstrual disorders
- Flushing of the skin
- Intolerance to heat
- Diarrhea
- Hair loss
- Protruding eyes
Left unchecked, hyperthyroidism may increase the risk of heart disease, stroke, or osteoporosis. Hyperthyroidism can also cause Graves’ ophthalmopathy, a condition that may result in eye pain, light sensitivity, double vision and, in rare cases, loss of vision.22
For people with hyperthyroidism, iodine reduces hormonal secretion, although scientists do not yet understand precisely how or why.23 Studies found that injections of iodine in hyperthyroid patients successfully slowed down thyroxine production.24 Sometimes radioactive iodine is used in severe cases.[7] Treatment depends on how severe the condition has become so always consult your healthcare provider for guidance.
Iodine, Mood, and the Brain.
Iodine helps ensure that there’s enough T4 and T3 in the brain to help it activate key neurotransmitters such as dopamine, norepinephrine, serotonin, GABA, and acetylcholine. Without enough T4 and T3, people may experience insomnia, fatigue, depression, and difficulty concentrating and focusing. As hormones, T4 and T3 regulate gene expression. Think of genes as a light switch and hormones as your hand; you use your hand to turn on or turn off the switch. Similarly, hormones turn on or turn off genes. Not consuming enough iodine can result in not having enough T4 and T3 to turn on the genes that regulate the very neurotransmitters that regulate your mood. To look at this more closely click here.
Serotonin – Studies have shown that low levels of T3 results in low levels of serotonin which can lead to decreased mood/happiness, depression, changes in social behaviour, and increased anxiety26
Dopamine – T3 also regulates the action of dopamine (which is converted into norepinephrine/epinephrine) which affects memory, feelings of pleasure and reward, focus and attention, and improved behaviour and cognition27
GABA – Is the ‘Zen’ neurotransmitter. Think of it as your brain’s natural benzo. T3 is needed for optimal GABA production and therefore helps you respond to stress better. Low T3 via low iodine intake can result in impaired GABA production and increased anxiety28.
Acetylcholine – As well-known as other neurotransmitters, acetylcholine is needed for learning and forming new memories. Low iodine intake and low T4 and T3 can result in low acetylcholine levels in the brain affecting cognition, memory, recall, and mood.29
Norepinephrine – While similar to epinephrine, norepinephrine acts like a neurotransmitter rather than its hormone sibling. Low iodine intake and low T4 and T3 levels can lead to low levels of norepinephrine leading to depression, anxiety, and low energy.29
Is Iodine Good for Anxiety? This question gets asked a lot. As mentioned above, iodine is crucial for two key neurotransmitters that are related to anxiety: serotonin and GABA. Given that some of the common symptoms of low iodine-related hypothyroidism such as depression, fatigue, and trouble concentrating, are associated with anxiety, ensuring you’re getting enough iodine is worth looking into.
Iodine Deficiency and Autism
Although scientists have yet to determine the exact origin of autism, some research has shown a potential link between iodine deficiency and autism. Research conducted by Arizona State University included hair analyses on 51 autistic children, 29 mothers of autistic children, and a control group. This study found that iodine deficiency in mothers could be a cause or exacerbating factor for autism. The study also found that children with autism spectrum disorder had up to 45% lower levels of iodine than the control children. 30
An Italian study found that women from an iodine deficient area of the country had reduced levels of thyroid hormones when compared to women who lived in iodine rich areas. 31 Researchers hypothesized “the imbalance of maternal thyroid hormone homeostasis during pregnancy was a consequence of endemic iodine deficiency may be responsible for the impaired psychoneurological development observed in children from that area. Appropriate iodine and/or thyroxine prophylaxis to women in that area may prevent the neurobehavioral, cognitive, and motor compromise of that population.”32 Proper thyroid activity doesn’t happen without adequate iodine levels.33
There is direct a link between the underproduction of thyroxin in the thyroid and weakened neural connections in the brain.34,35 Children with autism, and their mothers, consistently have lower iodine levels.30 The American Thyroid Association urges pregnant mothers to take iodine supplements, one reason is to ensure the mental health of their offspring.
For more information on each of the following, please see our blog, What Else Do I Need To Know About Iodine:
Where Do We Find Iodine?
How do I Know if I’m Iodine Deficient?
How Much Iodine Should I Take?
Types of Iodine in Supplements.
Side Effects of Iodine Ingestion.
Iodine and Medications.
How Do We Use Iodine as a Family?
Yours in health,
Jennifer Barham-Floreani,
Bach. Chiropractic, Bach. App Clinical Science
Registered internationally, no longer practicing as a chiropractor in Australia.
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