The human body is a complex, well-oiled machine that, in order to function properly, requires the right ratio of macro and micronutrients. But most of us don’t really understand what each nutrient does and why they are so important. As one of the first telehealth functional medicine clinics in the world, my clinical team and I have been helping people around the world understand these nutrients so they can begin to take back control of their health.

One of these essential nutrients is iodine. Read on to learn more about why you should be keeping an eye on your body’s iodine levels.

Iodine’s Role in the Body

Iodine is an essential trace mineral that synthesizes thyroid hormones. For example T3 and T4 stands for the amount of iodine atoms that it takes to produce these two thyroid hormones. Healthy thyroid hormone levels are vital to your overall health since every single cell of your body relies on thyroid hormones. In fact, low thyroid function, or hypothyroidism, affects around 20 million Americans, and 1 in 8 women will experience a thyroid issue in her lifetime. Thyroid dysfunction can lead to a wide variety of uncomfortable symptoms including:

• Low libido
• Weight loss resistance
• Fatigue
• Blood sugar imbalance
• Hair loss
• Brittle nails

Iodine deficiency can lead to an enlarged thyroid also known as a goiter as your thyroid gland tries to keep up with the demand for thyroid hormone production. Since the body doesn’t naturally produce iodine on its own, the only way to get iodine is through diet and supplementation.

On the other hand, too much iodine can actually increase thyroid antibodies and perpetuate thyroid symptoms in cases of Hashimoto’s disease. This is important to note since iodine is typically the main ingredient in thyroid supplements proving one of the main principles of functional medicine - that every person’s biochemistry is different and there is no “one-size-fits all” approach to health.

Considering this, studies are looking into the rise of iodized salt in favor of natural sea salt. By fortifying table salt with iodine we could be unknowingly contributing to the rise in thyroid problems through too much iodine intake.

The Importance of Labs

Because everyone’s health is different, it’s important to run labs to better determine where you stand with your iodine health. By looking at your iodine levels and thyroid hormones you can better determine the next steps for improving your health.

A functional medicine look at your labs is often more in-depth and includes a broader range of tests and considers a narrower range of optimal results. Blood tests can look at both iodine and thyroid hormones. Here are some of the thyroid markers that I consider in relation to iodine, what they actually mean, and what kind of results are ideal:

1. Free T4

This will tell you the levels of free or active form of T4. This will be low in cases of hypothyroidism but can be normal in subclinical, early stages of thyroid dysfunction.

Lab range: 0.8-1.8 ng/DL Optimal range: 1.0-1.5 ng/DL

2. Total T3

This lab shows us the total amount of the metabolically active thyroid hormone. It allows a doctor to check your body’s ability to convert T4 to T3 and to rule out an overactive thyroid.

Lab range: 80-200 ng/DL Optimal range: 100-180 ng/DL

3. Thyroid Antibodies

High levels of thyroid antibodies show an autoimmune attack against the thyroid. The overwhelming majority of low thyroid cases are on the autoimmune spectrum, the most common being Hashimoto’s disease.

Thyroid Peroxidase (TPO) Ab optimal range: 0-15 IU/mL Thyroglobulin Ab optimal range: 0-0.9 IU/m

Tools to improve iodine levels

1. Be mindful of salt

Switching to sea salt is one way to ensure you aren’t overdoing it on iodine. While sea salt does contain a small amount of naturally-occurring iodine, it’s not enough to make a significant difference in your overall iodine levels therefore this shouldn’t be something to rely on if you are looking to incorporate more iodine into your diet.

2. Focus on iodine-rich foods

Sea vegetables like seaweed, dulse, and kelp are an often overlooked food medicine that is packed with iodine. Kelp’s iodine levels are sky-high, with some varieties having up to 2,984 micrograms it has the highest iodine content of any sea vegetable. Kombu, a specific variety of kelp, has the highest iodine content.

Some other higher sources of iodine include:

• Cod (3 oz.) - 158 mcg
• Oysters (3 oz.) - 93 mcg
• Egg (1 cooked) - 26 mcg

3. Supplements

The recommended intake of iodine varies for each individual but in general men and women should be getting 150 mcg of iodine per day and pregnant women 220 mcg per day. If you determine that supplementation is necessary, work with your doctor to determine the right dosage for you.