We are independent & ad-supported. We may earn a commission for purchases made through our links.
Advertiser Disclosure
Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.
How We Make Money
We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently of our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

What are the Symptoms of Iodine Deficiency?

By Tony Hernandez
Updated: Mar 03, 2024

Iodine is a chemical found in the human body in very small amounts. Not having enough iodine in the body is called an iodine deficiency. Iodine is extremely important to the functioning of the thyroid gland, so an iodine deficiency causes problems with the thyroid gland. The physical symptoms of iodine deficiency include a slowed metabolism, fatigue, a loss of bone density and high blood pressure. Among the mental signs of iodine deficiency are depression, irritability and poor memory.

The thyroid gland produces the hormones T3 and T4, which affect most of the body’s systems. They help the body to produce heat and consume oxygen, and they aid in growth and development, including brain function. Iodine deficiency causes the thyroid to decrease its production of T3 and T4. This causes another gland in the body, the pituitary gland, to produce a hormone called thyroid stimulating hormone (TSH) in an attempt to stimulate the thyroid to produce more T3 and T4.

As a result of TSH, the thyroid can become enlarged. Enlargement of the thyroid gland is called goiter. The thyroid gland affects so many body systems and relies so heavily on iodine that an iodine deficiency is responsible for a host of symptoms, both mental and physical.

Perhaps one of the most obvious physical symptoms of iodine deficiency is slowed metabolism. This manifests itself as weight gain. Many people who complain to their doctors of weight gain that cannot otherwise be explained will undergo thyroid testing. There are other causes of thyroid problems, but iodine deficiency is one of the main causes.

Other physical symptoms of iodine deficiency include osteoporosis, or a loss of bone density; hypertension, or high blood pressure; fatigue; dry skin; hair loss; and puffiness in the hands or feet. People who have an iodine deficiency might also experience intolerance to cold, muscle cramps and infertility. These are only a few of the many physical signs of iodine deficiency.

Iodine deficiency also has mental symptoms. This is because it impairs the proper production of hormones that also affect mental function. The sufferer might experience depression, irritability, difficulty concentrating and poor memory.

Eating foods that are high in iodine should aid in restoring the thyroid gland to health. This will cause the thyroid to produce healthy amounts of T3 and T4, which will make many if not all symptoms of iodine deficiency go away. Shellfish are an excellent source of natural iodine and should be a staple in the diet of anyone with an iodine deficiency. Sea salt, iodized salt, cheddar cheese, eggs, mayonnaise and most fresh water fish also should be consumed.

One way to test for iodine deficiency is to use the iodine patch test. This involves placing a small amount of a chemical called tincture of iodine on the skin, leaving it on overnight, and seeing how much of it remains on the skin by morning. If the tincture of iodine is completely gone, the skin has absorbed it. The iodine patch test is said to be complete, and this indicates an iodine deficiency.

The Health Board is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.
Discussion Comments
By anon992644 — On Sep 21, 2015

I am a vegan, and eat no fish, no eggs, no fowl. I have all the symptoms, but the doctor says thyroid test is OK. I was on thyroid meds many years ago and within week all swelling went down and I felt good for a change. Perhaps I should try iodine? What is a good brand and where do I buy it? The grocery store? GNC?

By anon964975 — On Aug 08, 2014

Most people in the US are indeed deficient in iodine. The RDS is somewhere around 300 mcg (if memory serves), that however, is the base minimum.

The Japanese take in an average of well over 10k mcg, and they are world renowned for their youthful appearance and health, as well as low cancer rates. Immigrants from Japan to the US or other western countries usually start to develop these problems once they adopt the diet of the area.

Take some nascent iodine supplement, if you're reading this. Take it every day for a month and you will feel better. I started a month or so ago and my mind is sharper, and and I'm more alert. I sleep like a baby at night and I have energy I didn't know I had. Its not a "miracle cure" or "miracle substance" by any means, but it will benefit you.

Iodine still needs Tyrosine for proper thyroid function, but most people are not deficient in it. Still you can derive it from almonds and various seeds, bananas and dairy products like milk and cheese.

By Talentryto — On Jul 13, 2014

@ocelot60- Iodine deficiencies are actually not very common, because so many foods contain a lot of salt. Most people who eat a regular diet get enough iodine, whether they add salt to their food or not. However, there are things that can reduce the level of iodine in the body, such as extreme exercise and dehydration.

If your friend is having symptoms of an iodine deficiency, it would be a good idea for her to have her iodine levels tested to be sure that this is or isn't the problem. If by some chance she does have an iodine deficiency, more than likely, she should be able to treat it easily with diet and lifestyle changes.

By Ocelot60 — On Jul 12, 2014

How common is it for a person to have an iodine deficiency? I have a friend who has some of the symptoms that are mentioned in this article, and I was wondering if this is her problem. So far, all of the diagnostic tests her doctor has ordered have been negative, so I think it may be a good idea for her to have an iodine deficiency test. Does anyone have any suggestions?

The Health Board, in your inbox

Our latest articles, guides, and more, delivered daily.

The Health Board, in your inbox

Our latest articles, guides, and more, delivered daily.