Iodine and Hair Loss: What You Need to Know

Not seeing the full head of hair you expect when you look in the mirror these days? There are a lot of possible reasons why your hair might be thinning out, but one possible explanation could involve iodine.

Iodine is an important nutrient which is often overlooked, but which plays a key role in regulating a number of aspects of your health.  

Iodine and Hair Loss: What You Need to Know

If you are getting too little iodine—or too much—it is possible that you could find yourself losing hair.  

In this article, I am going to tell you everything you need to know about the link between iodine and hair loss, and how you can make sure you are getting the iodine you need for a full head of hair.

What Is Iodine?

First of all, let’s talk about iodine. Iodine is a trace element. It is a component found in two key thyroid hormones: thyroxine (T4) and triiodothyronine (T3).  

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It also is involved in the correct functioning of thyroid-stimulating hormones (TSH). These hormones, which are produced by the pituitary gland, are responsible for controlling the production of thyroid hormones.

If you do not get enough iodine or if you get too much of it, TSH levels are thrown off.

This in turn leads to improper production of thyroid hormones. The result may be hypothyroidism or hyperthyroidism.

It is also believed that iodine is important in immune system functioning, and that it may help counteract fibrocystic breast disease (FBD).

If you are pregnant, getting sufficient iodine is critical for fetal development. Iodine also is necessary for proper cognitive functioning during childhood.

The most famous use of iodine perhaps concerns nuclear fallout. After a nuclear event, the environment may become saturated in radioactive iodine.

Safe iodine supplements are taken in order to reduce the body’s intake of this radioactive iodine.

The National Institute of Health has published a great guide to iodine here. On that page, you can read about these uses and benefits of iodine in greater detail.

There are a range of other uses for iodine as well. For example, applying iodine topically to foot ulcers may help diabetic patients. Cancer patients undergoing chemotherapy sometimes use it to try and prevent mouth irritation from their treatments.

Could Iodine Deficiency Be Causing Your Hair Loss?

Now that you have some context for understanding the important roles that iodine plays in your body, let’s get back to the topic of hair loss.

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As mentioned before, getting the right amount of iodine is essential if you want to prevent hypothyroidism and hyperthyroidism. Too little or too much can cause issues.

That is where this discussion wraps back around to hair loss.

  • Hyperthyroidism is when your thyroid is overactive. It is linked to excess iodine.
  • Hypothyroidism is when your thyroid is under-active. It can result from iodine deficiency.

According to the British Thyroid Foundation, “Severe and prolonged hypothyroidism and hyperthyroidism can cause loss of hair.”

If you have this kind of hair loss, it will usually be characterized by the following traits:

  • It will be diffuse, not concentrated.
  • It will be relatively uniform.
  • There is often a delay of several months between detection of thyroid disease and hair loss becoming apparent. This may even happen during treatment.

Thankfully, hair loss which results from thyroid disorders is usually temporary. Once the thyroid condition is treated and hormones are once again in balance, hair growth should return to normal (or close to it).

The reason there is sometimes a delay between the diagnosis of a thyroid disorder and the onset of hair loss is because of the slow growth cycle of hair.

Patients who are taking a medication to treat their thyroid disorder or who are making other lifestyle changes sometimes make the mistake of believing that their treatments are the cause of the hair loss.

At this point, they may reverse their course of action and cease their treatments. This of course does not cure the hair loss. It only makes the entire situation worse.

If you do discover you have a thyroid condition (and they are quite common), you should treat it in order to protect your general health.  

Do not worry if the hair loss seems to start during the treatment. That is probably a coincidence. As your other symptoms abate, your hair loss should eventually subside as well.

Issues with Iodine and Thyroid Function May Also Lead to Alopecia Areata

You now know how too little or too much iodine may lead to a thyroid disorder, causing hair loss. But the relationship between iodine and hair goes even deeper.

It is common for patients with thyroid disorders to have autoimmune thyroid disease as well.  

This increases your chances of developing other autoimmune problems, one of which may be alopecia areata.

Alopecia areata is a disorder where your immune system turns against your hair follicles.  

Your hair then falls out. Alopecia areata hair loss is characterized by:

  • Hair loss which is concentrated, not diffuse.
  • The hair falls out in sections which are often circular in shape.

Sometimes alopecia areata is fleeting, but in other cases, it can progress to baldness. Thankfully the hair usually grows back. Repeated episodes may occur.

While on this topic, it should be pointed out that there are other autoimmune conditions which may sometimes lead to hair loss as well. A couple examples are lupus and polycystic ovarian syndrome (PCOS).

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How Common is Iodine Deficiency?

Just what are the chances you actually have iodine deficiency (or excess)? They may be higher than you think.

According to recent data, iodine deficiency has more than quadrupled over the past four decades. It is estimated that around 74% of adults who are otherwise considered to be “healthy” are not getting sufficient iodine.

Certain people are at a higher risk for iodine deficiency than others. These include:

  • People living in regions where the soil is deficient in iodine and there is no way to receive iodine-rich foods form other sources (typically isolated regions like the Alps and Himalayas).
  • Those who are getting insufficient iodine and are choosing to eat foods which contain what are called “goitrogens.” Goitrogens are substances that get in the way of proper iodine uptake.
  • Pregnant women. If you are pregnant, your RDA for iodine jumps from 150 to 220 mcg/day.
  • Anyone who doesn’t eat iodized salt (I will elaborate on this later in the article).

It is worth taking a close look at your diet and doing some calculations. How much iodine are you actually eating?  It may be less than you realize.

If you do figure out that you are particularly low in iodine, it could be throwing off your thyroid function, leading to hair loss.

It is less likely that you are getting too much iodine, but that is a possibility as well. If you are, it is time to curb your intake.

How Much Iodine Should You Get?

Before you can figure out whether iodine deficiency or excess could be responsible for your hair loss, you need to know whether you are getting the right amount to begin with.

Here are the recommended dietary allowances (RDAs) for iodine for all age groups:


Birth to 6 months: 110 mcg* 110 mcg*

7–12 months: 130 mcg* 130 mcg*

1–3 years: 90 mcg 90 mcg

4–8 years: 90 mcg 90 mcg

9–13 years: 120 mcg 120 mcg

14–18 years: 150 mcg 150 mcg 220 mcg 290 mcg

19+ years: 150 mcg 150 mcg 220 mcg 290 mcg

Dietary Sources of Iodine

Iodine and Hair Loss: What You Need to Know

If you are not getting enough iodine, one of the things you can do to remedy the situation is to get more iodine through your diet. Here is a list of foods and beverages which contain significant amounts of iodine:

  • 1 gram of seaweed: Anywhere from 11-1,989% DV
  • 3 ounces of cod: 66% DV
  • 1 cup of plain, low-fat yogurt: 50% DV
  • 1.5 grams of iodized salt: 47% DV
  • 1 cup of reduced fat milk: 37% DV
  • 3 ounces of fish sticks: 36% DV
  • 2 slices of enriched white bread: 30% DV
  • ½ cup of canned fruit cocktail in heavy syrup: 28% DV
  • 3 ounces of shrimp: 23% DV
  • ½ cup chocolate ice cream: 20% DV
  • 1 cup of enriched, boiled macaroni: 18% DV
  • 1 large egg: 16% DV
  • 3 ounces of drained canned tuna: 11% DV

There is also significant iodine in creamed corn, prunes, cheddar cheese, raisin bran, lima beans, apple juice, green peas, and bananas.

If you are eating a lot of the foods on this list on a regular basis, you may be getting enough iodine, but you will need to do the math and figure that out for yourself.

As you might expect, iodine deficiency is less common in the Far East where the intake of foods such as seaweed and fish is much higher than it is in the West.

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The Complicated Matter of Salt

Now, I want to touch down specifically on the matter of salt, because it probably accounts in large part for why so many people are not getting enough iodine.

For a really long time, I didn’t eat table salt. I had switched over entirely to sea salt, and I had decided on the stuff that was totally raw and unprocessed. After all, “natural” is always better, right?

I was buying a lot of “natural” non-enriched foods. So there was no iodine in my macaroni, cereal, or other foods either.

I wasn’t eating an abundance of seaweed, and while I did eat fish, it wasn’t like it was something I was doing every day.

Looking back, it occurs to me I probably was getting very little iodine in my diet in those days. And I was doing it all in the name of “natural” healthy choices.

During that time, I did end up developing some issues with my health—including a hormonal imbalance.  

Was that imbalance the result of my lack of iodine? I have no idea. There is no possible way I could say, because the type of disorder I have is one which is not yet very well understood from a scientific standpoint.

But one thing I can say, and that is that not getting enough iodine in my system probably did nothing to help.

It was only years later that I realized that I needed to be eating iodized salt.  So I started adding it back into my diet.

Now that I think of it, there was another reason I wasn’t getting enough iodine in those days well.

Not only had I switched entirely to “natural” salt which had no iodine in it, but I was also eating as little of it as possible.

Somewhere along the line, I had heard that “salt is bad for you,” and had taken it to heart.

Salt does contain sodium, and too much sodium is bad for your heart health.

But if you decide to give up salt in order to protect your heart, you will also be giving up a primary source of iodine.

So it is wiser to adopt a path of moderation (which is usually good advice when it comes to any aspect of diet).

According to the American Heart Association, you should try to restrict yourself to 1,500 mg of sodium per day.

The American heart Association also states that around three quarters of the sodium in American diets tends to come from processed foods, not from table salt.

So simply avoiding these processed foods (and eating out less at restaurants) may be all you need to do in order to make sure you are not overloading on sodium.

Reportedly, 1.5 grams of sea salt contains 468 mg of sodium. This is significantly less than 1,500 mg.

The type of salt that number pertains to is not iodized—I did not find the data for iodized table salt. But we can presume that the sodium content is likely similar.  

This means that you can feasibly get all the iodine you need from table salt without exceeding sodium limits, assuming the other foods you eat are not excessively high in sodium.

Here is a recommended iodized salt product you can consider:

  • Morton Iodized Sea Salt. This product measures the same way table salt does, making it easy to incorporate into your recipes. You can enjoy the taste of unrefined sea salt while getting the iodine you need.

There really are not a whole lot of other options for iodized sea salt.  As to iodized table salt, you can pick that up at pretty much any grocery store.

Don’t Want to Eat a Lot of Salt?  Seaweed Is Another Option

If you still aren’t all that keen on iodized salt, there is another excellent way you can load up on iodine, and that is to introduce more seaweed into your diet.

The iodine content of seaweed can vary a great deal, as indicated earlier (1 gram of seaweed might provide anywhere from 11-1,989% of your daily value of iodine). The best types are kelp, kombu, wakame, and nori.

Finding good deals on seaweed can take some shopping around. Here are some tips:

  • The seaweed spices in a jar are a good deal. Spicing your food with seaweed will not add as much iodine to your diet as eating a sheet of it, but the spices are delicious and last a long time.
  • Any seaweed sheets which have been salted, oiled or seasoned in any way are generally going to be significantly more expensive than those which have not.
  • Do not buy those little seaweed “snack” packs which are popular right now unless you want to waste money. You get tiny little sheets and you pay a lot for them.
  • The most cost-effective seaweed tends to come in large sheets. Buy the bulk packages and they will last you quite some time.

“How can I eat seaweed if I don’t have any sushi?” you might ask.

There are a ton of options. You can crush up the sheets and put them in rice or soup, or add them to other cuisine. You also can just eat them as a snack on their own.

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Consider these seaweed products:

Please note that you will find much cheaper deals on seaweed on average if you can buy it in person at a local Asian grocery store. Check around for one in your area if you want to save a lot of money.

Other Ways to Supplement with Iodine

If you prefer, you can also supplement your iodine intake using supplements. These may include capsules, tablets, or tinctures.  

Here are a few products which are popular and highly-rated:

  • Life Extension Sea-Iodine.  This product contains 60 vegetarian capsules, each with 1,000 mcg of iodine. The iodine has been derived from organic sea algae. This is a very cost-effective supplement. Aside from the ingredients used to make the vegetarian capsules themselves, there are no other added ingredients.
  • Pure Encapsulations Iodine. This is also a very affordable product which includes 120 capsules. The dosage is lower (225 mcg), but in some cases, that may be a better fit for certain needs.
  • NOW Kelp. These vegetarian capsules contain 325 mcg of kelp-based iodine. Each bottle comes with 250 in all.
  • Nascent Iodine Supplement.  You can also opt to take iodine in a liquid form. This tincture contains nascent iodine, kosher vegetable glycerin, and purified water. You can take six drops directly, or you can mix them in with juice and drink it. One serving (six drops) contains 2,694 mcg of iodine. If you want a smaller dosage, you can just take less.  The reason it is significant that it is “nascent” iodine is that this is the same form that your thyroid produces, which means your body has an easier time processing and using it.

Topical Iodine Treatment for Alopecia Areata

While you can take iodine orally to help correct deficiency and stimulate your thyroid to prevent hypothyroidism, there is another way it may be helpful when it comes to treating hair loss as well.

Iodine may be applied topically to treat alopecia areata. To do this, you can just use a tincture like the nascent one which I linked to above. This may help to stimulate growth.

Conclusion: Iodine Is An Important Nutrient for Healthy Hair Growth

Iodine has a complex relationship to hair growth.  It is involved with regulating the thyroid, which in turn can help you maintain a healthy head of hair.  But if you get too much or too little of it, it can result in hair loss.  If you develop an autoimmune condition as a result of a thyroid condition, that can also add to your hair loss—but iodine may be helpful in treating that as well.  

Because so many people are not getting enough iodine in their diets, it is wise to check your own iodine intake.  If you are indeed not getting enough, it may be time to start taking a supplement or eating more seaweed or salt.  If iodine deficiency is involved with your hair loss, correcting it should hopefully result in new growth!

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