Iodine is essential for the proper functioning of the thyroid.
The thyroid, a small butterfly-shaped gland located in the neck, is important for regulating the body's metabolism, growth, development, and more. Iodine is essential for the proper functioning of the thyroid, so much so that iodine deficiency symptoms can sometimes mimic the symptoms of hypothyroidism and/or lead to outright hypothyroidism (1).
This blog post covers how iodine impacts thyroid function and the many areas of the body that may be compromised by suboptimal thyroid function.
The Role of Iodine in Thyroid Function & Hormone Production
Iodine is an essential trace element that the body cannot produce, making dietary intake critical. The thyroid gland absorbs iodine from the bloodstream and uses it to produce thyroid hormones thyroxine (T4) and triiodothyronine (T3) (2). These hormones regulate many body functions as described below.
The process is straightforward:
Iodine Uptake: The thyroid gland captures iodine from the bloodstream.
Hormone Production: Iodine is incorporated into the structure of T4 and T3.
Hormone Release: These hormones are released into the bloodstream where they travel throughout the body to influence various areas.
Key Functions of Thyroid Hormones
When considering the impact of iodine deficiency or insufficiency on thyroid function, it is important to understand the diverse roles that thyroid hormones play in our well-being. Here is a list of the key functions of thyroid hormones T3 & T4:
1. Regulate Metabolism (3)
2. Promote Healthy Growth and Development (4,5)
3. Maintain Heart Function - Especially Heart Rate & Blood Pressure (6)
4. Regulate Body Temperature via Heat Production in Cells (7)
5. Affect Digestion & Gastrointestinal Motility (8)
6. Influence Muscle Strength & Function (9)
7. Maintain Skin Hydration & Texture and Hair Growth & Quality (10)
8. Regulate Menstrual Cycle & Reproductive Health (11)
9. Support Nervous System Function - Particularly Reflexes & Cognitive Function (12)
10. Promote Protein Synthesis for Tissue Repair & Growth (13)
11. Regulate Cholesterol Levels & Other Blood Lipids (14)
12. Support Psychological Well-being, Mood, & Mental Health (12)
An understanding of the wide range of thyroid functions in the body helps to make it clear why low iodine, and by extension low thyroid, may include symptoms like weight gain, dry skin, fatigue, cold limbs, brain fog, low mood, constipation, and more.
What To Do If you Suspect Iodine Deficiency?
The first step to take if you suspect that you aren’t consuming enough iodine is to assess your diet — a nutritionist can help with this. If your diet is low in iodine, you may wish to supplement with iodine-containing foods and/or iodine supplements. You may also wish to discuss a 24 hour urinary iodine concentration test with your healthcare provider.
- For more information about iodine testing, signs of iodine deficiency, and foods high in iodine, see: The Importance Of Iodine At Any Age - Dr. Green Mom
How Much Iodine Is Safe To Supplement With?
When supplementing a healthy diet in adults and teens, the usual dose of iodine is usually 150 mcg per day, which is equal to one drop of our Liquid Iodine With Kelp. For children iodine needs are lower and therefore the usual dose is 1 drop daily or several times per week. Higher doses may be required to correct a deficiency. Most people notice a boost in energy when supplementing with iodine, particularly if they are deficient.
The tolerable upper limit for iodine is 200 mcg (age 1-3 years), 300 mcg (age 4-8 years), 600 mcg (age 9-13 years), and 900 mcg (age 14+). Excess iodine consumption may cause health issues. Always check with your healthcare provider before starting iodine supplementation for yourself or your children.
Summary
The iodine-thyroid connection underscores the importance of this essential nutrient — iodine — in maintaining thyroid health and overall well-being. By understanding the role of iodine and ensuring a balanced intake, we can support our thyroid function and prevent related health issues. Remember, both deficiency and excess of iodine can disrupt thyroid function, so finding the right balance through diet, lifestyle, and supplementation is important.
RELATED ARTICLES
References:
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