Holistic Nutrition & Prevention

The unexposed iodine deficiency epidemic

By Nonie DeLong, ROHP, CNP

This week’s column was prompted by Bernadette in Bradford, Ontario, who wrote:

Dear Nutritionist,

I would like to know the most important supplement for a pregnant woman, in your opinion.

Can You Guess the Answer?

This is a great question, but before we get to the answer, let’s do a little quiz to see if readers can identify it. The answers will be included in my response below.

A lack of this supplement in children can cause serious problems with learning.

30-million children worldwide are known to have this deficiency.

It is a mineral.

A deficiency in adults impacts the heart, liver, and kidney.

Most people have sub-optimal to deficient levels.

High cholesterol levels can be caused by a deficiency.

Depression and fatigue can be caused by a deficiency.

Premature hair loss can be caused by a deficiency.

Cranberries are high in it.

Fluoride in the water supply increases deficiency.

Many people are not aware of this deficiency as an epidemic.

Nope! Not Folate!

While folate is essential during pregnancy, it is a B vitamin, not a mineral. And it’s well understood so most pregnancy supplements contain it. Most physicians know to advise it. But the supplement I feel is most important isn’t added in optimal levels to pregnancy supplement blends. It’s not as well known or understood, even by physicians. And the impact on the growing brain is astounding! So it’s super important to be aware and add it to your pregnancy vitamin list.

Did you guess iodine? It’s an essential trace mineral because it’s only needed in very small amounts. Despite this, most of the world’s population – it’s estimated between 72-96 per cent – are to some degree iodine deficient. And the amount we get from our diets has decreased drastically over the last 50 years – some professional organizations say by 50 per cent!

We are also exposed to more toxins that block iodine from being taken up by our cells. Fluoride and chlorine in our drinking water and bromide in our bread and baked goods add to the problem. You see, fluoride, chlorine, and bromide all compete with and displace iodine in the body, causing a myriad of health issues. Exposure to any one of them can take the place of iodine in the cells and increase iodine deficiency.

Historically, iodized salt was one way many people protected against extreme iodine deficiency, but more recent recommendations to cut salt from the diet may leave many with inadequate levels of this essential nutrient.

Additionally, modern farming practices create crops that are deficient in iodine and other minerals. Where fertilisers used to be natural, they are more and more chemical compositions that don’t replace missing nutrients in the soil. Too, people consume far more processed food now, which is certainly deficient in iodine and other nutrients. It’s even elective whether companies put iodine into salt, so the salt content in processed foods may or may not be iodized today.

Why Is It So Important?

You may not be aware of how important iodine is in the body. It’s required to produce the thyroid hormones for proper thyroid function. The thyroid is a butterfly shaped gland in the throat that regulates metabolism, energy, and body temperature. When it’s not working right, we often see dysfunction in weight, energy levels, sleep, brain function, sexual function, body temperature, and mood. Thyroid dysfunction also impacts all the other hormones in the body, because hormones work in tandem.

Low thyroid function is becoming epidemic in clients I see, especially those from South Asia. It causes a myriad of health conditions that can be really debilitating and what’s worse, it can go undiagnosed for long periods. This could be because it primarily impacts women and women’s health conditions are still frequently dismissed by health professionals and/or because thyroid function that is above the threshold for diagnosis can still often cause many health symptoms that have serious impact. So you can seem to be within the normal range on tests, but still have all the symptoms of the disease. Furthermore, the most common thyroid tests run by physicians only tests for one or two factors in thyroid health, they don’t test to determine if the gland is actually functioning optimally. In the extreme, when thyroid dysfunction goes unnoticed for too long, thyroid issues can cause auto-immune disease. This is particularly difficult to treat and impacts health immensely.


Deficiency Symptoms

Some health conditions that can be linked to iodine deficiency are:

  • Fibrocystic breast disease
  • High cholesterol
  • Heart, kidney, liver dysfunction?
  • Fatigue
  • Depression
  • Difficulty losing weight
  • Dry skin
  • Headaches
  • Memory problems
  • Menstrual problems
  • Constipation
  • Thinking problems
  • Memory problems
  • Muscle weakness
  • Joint stiffness
  • Hair loss
  • Sensitivity to colds
  • Tendency to get infections
  • Poor circulation
  • Impaired kidney function
  • Impaired liver and heart function
  • Increased risk of certain cancers

But What About Pregnancy?

Why is this the supplement I suggest most frequently for pregnancy? People generally know about the importance of folate, but this nutrient is still relatively under-appreciated. Additionally, we are seeing an exponential rise in learning, attention, and behaviour problems in children and iodine is especially important to the developing brain and intellect. Even a small deficiency can negatively impact the baby’s brain development. Children without enough iodine can suffer from learning troubles and low IQ, and severe iodine deficiency can stunt physical and mental growth. (Sources: 1, 2, 3, 4, 5) In fact, the WHO has stated that iodine deficiency impacts over 30,000 children worldwide and is the most prevalent cause of impaired cognitive development. 

From the (U.S.) National Institute of Health’s Fact Sheet for Health Professionals on Iodine:

“Most fruits and vegetables are poor sources of iodine, and the amounts they contain are affected by the iodine content of the soil, fertilizer use, and irrigation practices. This variability affects the iodine content of meat and animal products because of its impact on the iodine content of foods that the animals consume. The iodine amounts in different seaweed species also vary greatly. For example, commercially available seaweeds in whole or sheet form have iodine concentrations ranging from 16 mcg/g to 2,984 mcg/g.”

Link to Learning Disabilities?

As far as I can tell, there has been very little research into ADHD and learning disabilities and iodine supplementation and most parents/pregnant moms I consult with have no idea it’s even a factor in child development. But the data is there to show how essential it is. From a 1996 study of 100 male children from Moderate Iodine Deficiency (MID) and Severe Iodine Deficiency (SID) areas(PMID: 8615364)

“The results are suggestive of neural impairment as well as poor socio-psychologic stimulation, resulting in learning disability and lowered achievement motivation. Unless iodine nutrition is improved in the community as a whole, these abnormalities may prevent millions of children from the SID areas from achieving their full potential even if learning opportunities are made available to them.”

How to Supplement

Iodine works synergistically with other nutrients, as most nutrients do. Having low selenium (and most clients I see do) also contributes to an iodine deficiency. Optimizing selenium helps the body to recycle iodine effectively.

Selenium is best gotten from fresh Brazil nuts. Two to four a day is usually sufficient. Minerals from supplements instead of food are a less desirable source because they need to be wrapped in a protein to make them moderately absorbable. Natural rocks aren’t absorbed by the body, so we chelate them in protein to trick the body to take them in. This is not the natural way. In nature, water that flows through and over rock formations chelates the minerals naturally and holds the ionic form for us, which is very easily absorbed. Plants that take this up, then give us the nutrient. Animals that consume those plants hold the nutrient. Can you see the levels of dysfunction in today’s food systems?

Additionally, sea vegetables and seafood are generally rich in iodine. Using kelp as a snack and as part of a meal a couple times a week to supplement the diet is extremely beneficial.

The recommended dietary allowance (RDA) for iodine in Canada is much, much lower than what experts in thyroid health like Dr. Brownstein recommend for optimal health. We know the RDA is meant to keep us from keeling over dead, but how many of us are just walking dead? Let’s focus on what’s optimal if we are going to aim for something. Dr. Brownstein recommends closer to 5-50mg of iodine a day. That’s mg, not mcg! This would translate as 5000mcg to 50,000mcg/day. If we look at the RDAs we can understand the spectrum between what is optimal and what is sufficient to keep us alive. The RDAs are:

  • 1–8 years old – 90 micrograms (mcg) per day
  • 9–13 years old – 120 micrograms (mcg) per day
  • 14+ years old – 150 micrograms (mcg) per day
  • Pregnant mothers – 220 micrograms (mcg) per day*
  • Nursing mothers – 290 micrograms (mcg) per day
  • *The WHO recommends 250 micrograms (mcg) per day for pregnant women.

Now, taking the right form is imperative. Testing can be done via urine samples to determine a baseline and monitor levels, which is important if you’re supplementing in the higher range. Long term exposure can be seen in the hair (I always test hair for various reasons). Some telltale signs of too high a dose of iodine are a metallic taste in the mouth and sore or burning teeth and gums, nausea, vomiting, and stomach pain. I have never seen or heard of an iodine overdose in clinical practice. Properly functioning kidneys clear iodine from the body.

Keep in mind that bromine in store-bought baked goods is displacing iodine in the body. Coupled with problems with glyphosate-sprayed red wheat and gluten sensitivity, we really need to consider if flour-based baked products have any place in a healthy diet today.

There are several foods that are rich in iodine that we can use to naturally boost our levels:

  • Seaweed/kelp
  • Cod
  • Scallops
  • Yogurt & raw milk
  • Cranberries
  • Shrimp
  • Tuna
  • Eggs
  • Potatoes
  • Lima Beans
  • Navy Beans

Of course, crops are only as rich in iodine as the soil to grow them. A few ways I suggest clients get more iodine in their diets is by having organic yogurt in their smoothies and adding kelp to their salads or snacking on seaweed crisps. If you’ve never tried them, these are light, slightly salty, paper-thin green seaweed wafers that come in a little pack. They are very satisfying and a pack contains close to 60 per cent of our minimum daily iodine requirement, which is a good start. I also advise many clients to add kelp flakes to their foods and replace iodized salt with Himalayan sea salt that contains a broad spectrum of minerals.

Kelp flakes floating in organic miso broth is one of the most nourishing foods you can take in. It helps balance the microbiome and contains minerals and amino acids. It’s a wonderful digestive or morning hot drink. Make it with bone broth and miso to take it to a totally different level and heal a multitude of digestive woes.

The best way to get iodine is from iodine-rich foods, as we always want to get our nutrients from foods when we can. After that kelp tablets are a safe way to supplement, taking only what a client needs to get levels into the normal range. Iodoral supplements are very beneficial and recommended by Dr. Brownstein. For iodine supplements I recommend seeing a licensed nutritionist or reading Dr. Brownstein’s books to learn about how to understand which dose is best.

Listen to Dr. Brownstein talk about iodine here.

Thank you for the great question, Bernadette!

As always readers can write me at nonienutritionista@gmail.com with their nutrition and health related questions. I also provide 1:1 consulting for those who need more personal help with their mental and physical health via my site at hopenotdope.ca.

If you want to learn more you can find other articles like this one at askthenutritionist.substack.com.


Nonie Nutritionista

Nonie DeLong is a registered orthomolecular health practitioner, licensed nutritionist in both Canada and the U.S., and student of the Ontario College of Homeopathy.  

Photo credit: © RODNAE Productions via Canva.com

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