Home General Info & Awareness Spotting The Signs Of Iodine Deficiency

Spotting The Signs Of Iodine Deficiency

by InvisiblyMe
A green coloured diamond pattern background with a large white circle in the middle where the title can be found : Spotting the signs of iodine deficiency.

Iodine rarely gets a look in when it comes to general health and wellbeing unless you’ve already developed a thyroid problem. Here’s a look at what iodine is, the sources of iodine, the symptoms of iodine deficiency, and how to get tested.

What Is Iodine?

This chemical element is a vital contributor to functions such as regulating energy, keeping you warm, and helping your body to produce adequate thyroid hormones. Your thyroid, located in the neck, utilises iodine to make the hormones that support your body.

We don’t tend to think of the foods containing iodine as we might with things like calcium, magnesium, iron or vitamin C. The body doesn’t create iodine so it needs to come from your diet or supplements. 

How Much Do Iodine Do We Need?

Guidelines suggests adults should aim for 150 mcg (micrograms) each day. Pregnant women require 50% more. Iodine is naturally found in seawater and the soil. Iodine deficiency is often found in countries where iodine in the soil is lacking, such as South and Southeast Asia, parts of Europe and New Zealand.

What Are The Best Sources Of Iodine?

Iodine can be found in various foodstuffs at differing quantities. Shellfish, seaweed and fish are packed with iodine, though this can vary depending on what country products come from (ie. seaweed from Japan is usually higher in iodine). Dairy products are another source. If you don’t eat fish and you’re not able to eat dairy, then think things like nuts, fruit and vegetables, potato and cereals.

There are also fortified products, like plant milks or ‘iodized’ salt, with added iodine. To support your diet or boost your levels due to deficiency, it’s also possible to use supplements. 

A birds-eye photo of a white marble tabletop on which is a range of food products, like seafood, milk, dairy, leafy vegetables. In the middle is a mini chalk board with 'iodine' written on it, to show the dietary sources of iodine.

Iodine Supplements

It’s always best to check before using any supplements, especially if you’re taking other medications so as to avoid any interactions. For example, iodine with certain blood pressure medications or diuretics can cause potassium to rise, and taking iodine with hyperthyroidism medications could reduce thyroid hormones too much. 

It’s also worth keeping in mind that intake shouldn’t go above 1,100mcg as too much iodine can also be harmful. What’s more, a regular intake in supplement form could be problematic if your body isn’t used to it (ie. you get very little iodine in your diet) or if you already have a thyroid condition. 

Getting Iodine Levels Checked 

Speak to your GP if you’re concerned of the possibility of iodine deficiency or thyroid issues.

Your doctor or endocrinologist can do a urine analysis to test your iodine levels, but confirming deficiency isn’t always that straightforward. A urine test will tell you what sort of iodine intake you’ve had recently but not the bigger picture. Iodine levels can vary quite considerably from hour to hour, let alone day to day. As such, 10 or more tests are often required to get a more accurate picture of what’s happening. 

Normal levels and the level at which deficiency is diagnosed may vary between countries and practices, but the American Thyroid Association notes deficiency as involving a urinary iodine concentration of lower than 100μg/L (or less than <150 μg/L in pregnant women).

Many with thyroid conditions don’t have iodine mentioned to them by medical professionals. If you have concerns or questions, always ask and persevere.

You can also get private home tests if you’re in the UK from Medichecks. You can find more information on the Medichecks service here. They have an iodine urine test, as well as various thyroid blood tests available do to at home as a fingerprick sample or in clinic by a nurse. Browse the range of home blood tests at Medichecks & use the code INVISME10 at the checkout for 10% off.

What Are The Symptoms Of Iodine Deficiency? 

There are a few symptoms to be aware of that could indicate low levels of iodine, but symptoms usually don’t present until a deficiency is more severe. 

1. Enlarged Thyroid Gland / Goiter

If daily iodine intake drops below 100mcg, your body produces more TSH (a thyroid hormone). In turn, this can lead to the thyroid gland becoming enlarged, which is one of the most commonly experienced symptoms. A very large goiter may be uncomfortable or cause troubles with breathing or swallowing, but often the enlargement isn’t discovered until a CT or ultrasound is done. 

2. Hypothyroidism / Underactive Thyroid

This can be triggered with daily iodine dropping below 10 – 20mcg, and hypothyroidism can come with a host of symptoms. For instance, dry skin and hair, weight changes (often gaining), fatigue, constipation, muscles aches, depression, hoarseness, puffy face and cold intolerance. Such symptoms are quite common across various conditions, so having hypothyroidism properly diagnosed is vital; once diagnosed, iodine should be checked and a treatment plan should be put in place. 

3. Symptoms associated with low iodine and poor thyroid hormone production can also include :

Fatigue, unexpected weight gain, dry/flaky skin, hair loss, impaired memory, heart rate changes, feeling colder than normal. For women there can also be issues with pregnancy and heavy or irregular periods.

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As always, please raise any concerns with your GP or specialist. If in doubt, ask.

Have you ever had issues with iodine?

Caz  ♥

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Anne Fraser @theplatinumline.blog August 31, 2021 - 4:15 pm

I have an underactive thyroid. I think symptoms are very much caused by slowing of the metabolism especially in cold weather. It is often a family problem. My mum suffered from it as well.

InvisiblyMe September 3, 2021 - 3:50 pm

The cold weather can make various conditions worse, including hypothyroidism. I’m sorry your mum had to contend with it as well. I hope your medication, if you take it, helps to alleviate some of the symptoms ???? xx

doublegenealogytheadoptionwitness August 31, 2021 - 4:21 pm

Interesting. One does not often hear of an iodine check – maybe overlooked these days. Thanks.

InvisiblyMe September 3, 2021 - 3:52 pm

I agree, you don’t tend to hear about it much, if at all. It’s very much under-appreciated. Thanks for reading ???? x

Ashley L. Peterson August 31, 2021 - 4:32 pm

I didn’t realize that iodized salt wasn’t common in the UK. In Canada, and I believe in the US, aside from sea salt, your basic table salt that you buy at the grocery store is all iodized.

InvisiblyMe September 3, 2021 - 4:24 pm

It’s strange, isn’t it? You’d think all the big Western countries would be in alignment about something like this, but iodised salt isn’t widely available here, just within certain stores that stock such brands.

Cheryl, Gulf Coast Poet August 31, 2021 - 5:03 pm

I once tried a kelp supplement, and my next blood panel was abnormal. I stopped the kelp and it was OK again. As you say, you have to be careful with iodine supplements. Thank you, Caz for an informative article. <3

InvisiblyMe September 3, 2021 - 5:06 pm

I’ve never tried kelp but it’s interesting that it threw something out of whack for you. I’m sorry that it did, though I absolutely agree with the point here. While “natural” supplements can be great, it doesn’t mean they’re safe or suitable for everyone. It’s hard to know really unless you can test for a deficiency, so I think sometimes it’s trial and error while keeping a cautious check of how things go. Thanks for the comment, Cheryl ???? x

Nanette “Champ” Gorena December 23, 2021 - 10:09 pm

I read kelp has a bad effect on thyroid. Along with Brussels sprouts, broccoli to name a few

InvisiblyMe December 24, 2021 - 2:44 pm

It seems that eating kelp within the recommended limits is okay for most, though not all – it’s kelp supplements that should particularly be treated with caution as these can have much higher concentrations and cause problems for those with thyroid issues. Really good to know the foods and supplements that can cause problems too, so thanks for adding this, Nanette! x

Cynthia Covert August 31, 2021 - 5:14 pm

Iodized salt is used pretty much everywhere in the US. Which for me is unfortunate being that I am allergic to iodine, LOL..Cooking for my self is best. I use sea salt and not all, but many also carry salt without iodine. However, finding restaurants that cook without iodized salt is very hard. Ask the wait staff and nobody knows. Bad thing is that it is not always labeled in bulk sales. But I can tell within minutes if something was baked or prepared with iodized sale because my hands will break out in a blistery rash.

Thanks for writing about this, because after reading the list of foods it is found in, I now understand why I feel like crap after eating them.

InvisiblyMe September 3, 2021 - 6:03 pm

D’oh! We don’t have iodised salt as standard here in the UK, which could be useful for some people. It’s just typical that where you are it’s everywhere and you’re allergic. Salt seems to be added to a lot of things so I can see why cooking your own stuff is best so you know exactly what’s in it. It sounds like an horrendous reaction you get. It’s surprising to see where iodine is found so perhaps swapping out some of those foods will help you a little. Thanks for sharing your experiences, Cynthia ???? xx

Carolyn Page August 31, 2021 - 10:41 pm

Great information, Caz.
I love sushi and have it a couple of times each week. Add a couple of salmon meals and here’s hoping the iodine levels are happy!

InvisiblyMe September 3, 2021 - 6:03 pm

Sounds like a good diet to keep your iodine and thyroid balanced, Carolyn! ???? xx

Sandee September 1, 2021 - 12:01 am

Good information to know. I didn’t know this about iodine. Thank you for all the research you do.

Have a fabulous day, Caz. Big hug. ♥

InvisiblyMe September 3, 2021 - 6:04 pm

I’m glad this helped you learn something new, Sandee. Iodine barely gets mentioned so I thought it might be good to cover it. I hope you have yourself a great weekend lovely xx

Despite Pain September 1, 2021 - 12:54 pm

I’ve never heard of iodized salt. I had a bunch of blood tests done recently, so hopefully that was on the list. Helpful post, Caz. It’s really something that I’ve never thought about before.
Hope you’re doing okay.

InvisiblyMe September 3, 2021 - 6:06 pm

Iodine rarely gets a look in, and I don’t think I’ve ever had any tests for it. It’s a shame not many doctors think to include it so I hope they do a thorough work up for you. Fingers crossed you get your results soon, Liz ???? xx

Kymber September 1, 2021 - 2:19 pm

Another interesting and informative article, Caz. xoxo I think you’ve hit upon some very important points.

InvisiblyMe September 3, 2021 - 6:07 pm

Thank you, Kymber, I’m glad you liked it. I hope you have yourself a restful weekend ???? xx

Masha September 1, 2021 - 2:46 pm

I only recently found out about iodine deficiency, up to that point I wasn’t getting enough iodine in my daily diet, I have an inactive thyroid and iodine supports the health of my thyroid, but like you mention here, I have to be careful not to consume too much or too little. I also haven’t talked to my doctor about taking iodine supplement and how it can interact with medications that I take, good point. Thanks for posting this. xo

InvisiblyMe September 3, 2021 - 6:09 pm

It’s not something that often gets mentioned, is it? I imagine a lot of people are unaware of iodine, or whether they’re getting enough/too much. It sounds like a good balance would be very important for you given your thyroid function, so I hope your doc can advise on your current level and what to safely do to get it optimal. I hope the post could be helpful, Masha ???? xx

Terri, Reclaiming Hope September 1, 2021 - 4:36 pm

Another great post Caz! I had sub-acute thyroiditis years ago, and one thing my Endocrinologist commented on was how my TSH levels started to normalize after I had a scan that involved swallowing an iodine-based capsule for contrast. That made me realize just how important getting enough iodine is to our thyroid health. Thanks so much for sharing this information – it could potentially keep someone from going through what I did.

InvisiblyMe September 4, 2021 - 4:17 pm

That’s really interesting about the little extra iodine in the capsule making a difference to your TSH. Do you now add iodine/ensure to eat more sources of iodine? Iodine rarely gets a mention so I thought it important to write about it. I hope it can help someone else, and I’m glad your endocrinologist spotted the issue because it couldn’t have been easy dealing with sub-acute thyroiditis like you did. Thank you for the comment lovely xx

The Oceanside Animals September 1, 2021 - 4:50 pm

Chaplin: “We don’t know about iodine, but Mama has noticed that my black furs are turning a bit brownish so she thinks I’m not getting enough, um, tyrosine, I think it was, in my special food and she’s looking for a supplement. I’m hoping it’ll be fish or mouse or bird or Charlee’s food or something like that.”
Charlee: “Stay away from my food, Chaplin!”

InvisiblyMe September 4, 2021 - 4:19 pm

Your mama is smart. I’ve never heard of tyrosine before. I hope Charlee’s food gets your furs looking black again! ????

annieasksyou September 1, 2021 - 5:53 pm

A valuable post on a rarely discussed topic. Well done, Caz!

InvisiblyMe September 4, 2021 - 4:29 pm

Thank you Annie, I’m glad you liked it. Iodine really is very rarely mentioned, but it can nonetheless be pretty important. ???? xx

Blushstopshere September 2, 2021 - 6:41 pm

I’ve been having a daily seaweed snack to see if that will help my underactive thyroid.

InvisiblyMe September 4, 2021 - 4:47 pm

That’s a great idea – I hope it can be helpful! ????

James Viscosi September 3, 2021 - 3:45 pm

I take a number of supplements for vitamins and minerals ― after “The Event”, I went over them with my neurosurgeon to make sure they were okay. For me, the most important one, I think, is calcium citrate, not because I need the calcium, but because a doctor once told me there was evidence that the citrate reduced the incidence of kidney stones. I used to get those suckers every 5 years like clockwork, and it’s been over 10 years now since my last one, so maybe it works … *knocks wood*

InvisiblyMe September 4, 2021 - 11:18 pm

Wow, I had no idea calcium citrate and helping to prevent kidney stones. It’s brilliant that’s done the trick keeping those nasty things away for you for a good while now – Long may it last! ????

Blanca September 3, 2021 - 7:22 pm

I suffer from underactive thyroid but fortunately my levels of iodine always came fine. But funnlyy enough, I can´t take supplements of iodine because it triggers my autoimmune system to attack my thyroid gland.

InvisiblyMe September 4, 2021 - 11:21 pm

I’m sorry you’ve got an underactive thyroid but it’s great your iodine has been checked and found to be fine. It’s interesting how iodine supplements can have an adverse effect indirectly on your thyroid because of your immune system. It’s a fine balance with iodine, isn’t it? Thank you for sharing your experiences ???? x

Lauren September 3, 2021 - 8:01 pm

This is a really interesting and useful blog post for many people to be aware of as your health is so important. Thank you for sharing.

Lauren – bournemouthgirl

InvisiblyMe September 4, 2021 - 11:23 pm

Thank you, Lauren – I hope it can be of use to someone in some way, even if just to make them aware of the potential for iodine imbalance. I hope you have a restful Sunday tomorrow! xx

Holly September 4, 2021 - 9:13 pm

You’re absolutely right Caz; iodine is something few think about. Here in the U.S., iodine is already included in so many foods. We prefer to use Himalayan pink salt when it comes to salt, but I wasn’t aware that rich amounts of iodine were also found in some of our favorite foods. Although I don’t like fish, I do love potatoes, fruits, veggies, and nuts!

I did take an Iodine supplement once that had herbs geared specifically for under-active thyroid. That was an issue I was dealing with, fairly severely at that time. Honestly, it really did help with my energy levels and other symptoms of low thyroid. What you said is true though; supplementing without really knowing what’s going on in our bodies is a dangerous thing to do! We could have dangerously high levels of something and be clueless of it until it’s too late. Even though I’m a big big believer in natural health – it’s still wise to use good sense.

Thanks for sharing this great article, Caz. It’s important to be reminded of vitamins, minerals, and other chemical compounds in our bodies that are often overlooked. ❤️ Holly xx

InvisiblyMe September 6, 2021 - 5:02 pm

It’s interesting how iodine is added over in the US, but not the UK. Very little attention is ever given to iodine so many people don’t know about it, how you can be deficient or what the sources are.

I’m sorry you had such a horrible time with your thyroid, but I’m glad the supplement could be helpful. It’s hard to know what to do for the best when you don’t know what’s going on with your body and different levels of things, I absolutely agree. I suppose for those who can’t get certain things tested, whether it’s because of price, lack of access to a doctor or the doctor simply refusing to do it, it’s a case of being mindful of unwanted effects from supplementing. It might all be absolutely fine, but overdoing things or not tolerating them well is still possible.

Thank you for the great comment and for sharing your experience, Holly ???? xx


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