sea kelp

Q. When my internist noted a low-normal thyroid value, he suggested a thyroid supplement. I suspected I had an iodine deficiency from years on a low-salt diet. I proposed a trial of sea kelp and he agreed. Two 100 mg tablets a day brought up the thyroid value to normal and warmed my cold toes. I also noted my foot fungus receded 90 percent.

A. Using iodine to treat an underactive thyroid gland is controversial. Very few Americans get too little iodine, though your years of avoiding iodized salt may have resulted in an inadequate iodine intake for you.

In a case report, a woman who used kelp as an iodine supplement aggravated her thyroid disease (Journal of General Internal Medicine, June 2006). We’re glad you worked with your doctor and got good results, but we don’t generally recommend this approach.

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  1. Sharon

    Hi all I to am having problems with hypothyroidism and my doctor does not believe in treating it with meds because it is on the low side of normal, I als have an enlarged womb and a very large fibroid that I am waiting to have removed but my ob gynaecologist is thinking about a hysterectomy so I await further tests, I put myself on kelp without any advice from anyone and it seems to work on my hair and nails but nothing else and now after reading about the possible over dosing off kelp , I am wondering if my selinium supplement might be better, I have also taken both together with terrible side effects. So I would be so grateful for any advice, kind regards Sharon

  2. Jacqueline
    Chicago, IL

    I just started using the powdered kelp because my thyroid is not functioning properly. I’m always tired, thinning hair and eyebrows, brittle nails and can’t seem to lose weight no matter what I do. I’ve been using the powder for almost a week now and it makes me tired but when I sleep, it is very soundly. I have also noticed my memory has improved.

  3. Carissa

    I tested low for thyroid 5 1/2 weeks ago. Was prescribed synthroid but only took one pill. My sister has relieved some of her symptoms by adding kelp powder to her salt. Took her a year to test within the normal range, but that inspired me. I’m always leery of prescriptions, try and take a natural approach ( I have my babies at home in a birthing tub, haha) I was not happy with the prospect of a life long pill that comes with its own side effects.

    Anyway, the day after the diagnoses I started taking kelp tabs (600 mcg). I also started eating a few Brazil nuts (2-3) every day or so for the selenium. I was making Maca smoothies every morning.

    I started wondering if I was just feeling worse because I know “knew” I had low thyroid, like if was all mental, but I was feeling soooo low energy. I happened to accidentally miss my maca smoothies two days in a row and felt better. I decided to test the theory and do a week on and a week off of Maca root powder. After the week off I felt so much better that I didn’t want to go back on them. I don’t want to feel like crap again for the sake of fulfilling my experiment. So pretty sure it was the culprit, but not positive. I continued with the kelp and Brazil nuts for about 3 more weeks without the maca.

    Found out I was pregnant 4 days ago and I know that low thyroid can cause miscarriage and even birth defects / low IQ in babies. Heaven forbid! I went and had my TSH levels rechecked just to make sure the kelp was working for me. IT WAS NOT!! It apparently does not work for me like my sister. My TSH levels went from 7.3 five and a half weeks ago to 11. 7 today. I’m soooooo bummed. I really want to treat this naturally but I can’t endanger my baby to figure it out. Any advice would be greatly appreciated. I feel like I’m in a position where I need to just do what the doc says because everything I tried backfired and there’s too much riding on my figuring this out NOW.

    Just my experience, but know that kelp and/or maca doesn’t work for everyone.

  4. Doly

    Two members of my family is with goiter, my mom and one sister. They took natural vitamins and big lump in the neck was gone. For me, it didn’t work as I didn’t religiously took the vitamin. After 3 years, I notice my lump gets bigger and bigger. Although I had normal TSH yearly, I had to consult a doctor. When I took levothyroxine, I have fainting spells in the morning and night time.
    I’m very scared I might fall when walking without someone to look at me. There was a time, when I look at the switched lights at home, computer monitor or any glaring glass in the office, street lights in the city. I have to close my eyes for a second not to fall. I knew I might loss consciousness. So I researched and this is the side effects of levo in the eyes. I told my doctor, he laughed at me. He said, I’m dreaming. No I am not as I really fall in the bathroom after switching ON the lights with my head up and looking at my things to use.
    Sure, he doesn’t tell me side effects. I respect my doctor’s advice, but I insisted, I stopped the levo. My TSH were normal anyway but with enlarged thyroid growing bigger. I had been to three doctors prior to that. 2 doctors recommend surgical operation which I’m very scared of. The other is a homeophatic doctor. I remain with 1 medical endocrinologist doctor. AFter 1 aspiration, I felt better, 2nd aspiration, quite bit painful but I felt good. I started using kelp (dried seaweed by Korea) available in natural vege stores. I have read this is available in the City as there are many koreans. I knew I feel better concentrating in my work this time. I work in a bank and for the past years, I felt my memory is so bad. I’m sure I am lack of iodine.
    I want to share in the future what’s gonna happen to me after me taking up this kelp, spirulina tablets (green algae) in AM and a natural green tea with honey. Wish everyone to be well.

  5. Taj S.

    I have been told I have low thyroid readings. I know nothing about thyroid but in 3 months I will see if it has changed and may have to take meds at that time if it is worse. Meanwhile, I have been told to take kelp and also selenium supplements. I guess I am to take them together….?
    Has anyone tried this before meds were prescribed? Can I get some feed-back on your experience and if it helped or made you sick? I have had hair loss and fatigue, high cholesterol, thinning brows, weight gain and dealing with osteo-arthritis and fibromyalgia so I ache everywhere anyways and may not be able to detect side effects of kelp and selenium. I would love to hear your comments on this, Thanks.

  6. BJM

    20+ years ago I was having thyroid problems, missed periods, couldn’t get pregnant, tired ALL the time. Sleep all day and night and still be tired. A friend suggested I tried kelp. 6 months later I had more energy, periods were regulated, then I got pregnant. YAY KELP
    My fiance is having problems with his tyhroid and would like to try a more natural supplement so I’m going to start him on some kelp.

    • glo
      san fran

      hi there, I’ve been hypo for over 7 years. check out the mary shomon site – she has lots of great advice. also learn to read your own tsh results, be leery of doctors who won’t Rx Armour, and be leery when they tell you that your TSH is normal- in the greater scheme of things this is almost irrelevant. normal doesn’t mean optimal for you. if a dr. treats you based on your test results only and not your symptoms, immediately find a dr. who will treat you based on your symptoms. you may want to try a naturepath dr.

      good luck,

    • Jolie

      Check your vitamin D. I have been in pain and stiff joints for years. 3 months ago I was tested for vitamin D and came out low. The doctor started me with Vitamin D3, 50,000 iu weekly for 3 months then she will check again to lower it to 2000 iu weekly for the rest of my life. Within 3 weeks my pain and stiffness got like 50% better and energy improved.

  7. Joe

    Kelp, selenium, Maca, this combo is very powerful.

  8. Brandi

    I was diagnosed with hypo around 13 years ago. 16 yrs ago I had my first son. Soon after that I had to have my gallbladder removed due to gall stones. It has been brought to my attention now that being hypothyroid can cause gallbladder problems. When they removed mine they did not mention or check my thyroid. At this point in time I do believe I would have been diagnosed hypo if checked.
    After removal of gallbladder I became pregnant with my second child. After the birth of her I felt like I was ovulating every day all day. Very weird feeling so I went to my OB and explained to him the problems and he immediately tested my thyroid. Back then I was started off at .5mg synthroid. Got the medicine and went on my way. Got it checked every 6 months like I was told and eventually my dose started getting increased. I still didn’t think twice about it. I had my last child 9 years ago. After having him my thyroid function decreased even more so again my dose kept increasing. I still was not informed of the thyroid and the role that it plays in your health. Completely my fault for not researching before now to make myself more knowledgeable on this disease. In January of this year my health started taking a big dive. I was having panic attacks, breaking out in hives, I didn’t want to leave my house. I felt like crap every single day so what do the docs do put me on 200mg of Zoloft. At that point I was ready to try anything.
    Here I am almost 10 months later still on the 200 Zoloft, still going through all the symptoms back pain, extreme leg pain, extreme fatigue, no eyebrows, hair falling out, loss of toenails and I can not keep any weight on. Yes I am hypo. So they tell me. My body temp is always low. My blood pressure is always low. I am on .150 synthroid daily and still feel no improvement. :(. I am so confused as what to do. I can’t continue feeling like this. Someone just told me today of kelp.
    Is it dangerous to try kelp while taking synthroid ??? Please help

  9. brooklyn23

    I know I’m late, but I wanted to know how did everything with the kelp work out? I’m on levothyroxine 0.05mg and I think my test for august came back fine. But I’m gonna lay off that once my kelp supplements come from walgreens and take that until my next blood test which will be like in november.

    • dbynum

      Curious – Did the kelp work for you? I know that the medical community does not recommend getting off and on Levo so, I was wanting to follow your results!

    • glo


      If you read this – try switching to armour – this has t4 and t3 and it’s natural. synthroid only has t4 that’s suppose to convert to t3 but this is not always the case. also find a dr. that will treat your symptoms and not your labwork. you must learn to interpret your own labwork.

      good luck,


  10. Jean l.

    I am still not taking the thyroid hormone which was originally prescribed for me years ago. I buy as many things as possible. “low salt or no salt” and then add iodized salt for flavor. I feel fine and have plenty of energy. Body temp is usually 98.6F or close to that. I also try to eat foods fairly high in iodine, such as fish or other seafood.

  11. GC

    Hypothyroid, but underweight, exercise 90min/day, vegetarian 25 years – am now 44, no blood disorders, eat very little ‘junk’ or sugar but plenty fruit. Think am low vit b12. Vestibular problem due to traumatic head injury. How ‘hypo’?

  12. Charlie

    Jean I just read your post and I would like to know how your Hypothyroid symptoms are now after several years. Are you still supplementing your RX for a more natural approach? I just started on kelp caps and I have been hypo for many years. Looking for alt thyroid help for if there comes a time when prescriptions might now be available.

  13. Diana

    I was diagnosed with low thyroid function and prescribed Levothyroxine over a year ago. I started to have itchy skin rashes about one month after commencing Leevothyroxine. I have been prescribed many different ointments and creams, and have taken three courses of prednisolone. The rash always comes back, and at present is widespread. I have decided it must be caused by the thyroxine and have just stopped taking it and am taking Sea Kelp 800mg daily. This is only day 2 so no improvement yet. What do you think?

    • Danielle

      Hi you all need to eat healthy green tea high protein foods low carbs I was a size 6 uk and went to a size 14 in space of a couple of months then got diagnosed with underactive thyroid and now with in the year I am a uk size 8 I’m on levothyroxine on 50mg I double up on my tablets don’t care what doc said in space of 6 mths was level I also take t9s they help too

      • Danielle

        Also take vitamin c

    • brenda
      new carlisle, IN

      i’m newly hypo & took levothyroxine & had what i would call cystic acne around my mouth & jawline. it was red under the skin bumps that hurt & some fluid filled, itchy & very ugly. i went to the doc & he took me off so waiting six weeks to go back. was wondering if yours was like that & if it cleared up & are you still taking kelp & how is your low thyroid & TSH levels now? I did find a site that had 80 comments from people who had cystic acne from taking the levo & took it to my dr because he said he had never heard of it. Thanks for any help.

  14. Val

    In case you want to try kelp in food, let me suggest a very simple combination that tastes pretty good. Be sure to use granulated kelp, not powdered. Take half a sliced Haas avocado and spread it over a slice of whole grain toast. Sprinkle the granulated kelp on top. I like about a quarter teaspoon. I used to eat this in the 1970s, but I tried it a couple times lately and it is still pretty tasty and pretty healthful.

  15. carrie

    i have gained 50+lbs since I had my thyroidectomy + feel worse than before an extra moody even on 150mg of thyroid meds. why? if would have known this I prob. wouldnt have done it.

  16. NCS

    I have had low TSH readings for the past 4 years, however my doctor, responded that it was not out of the range when I mentioned this several times. (I am over 60, and still very active, but gaining belly fat, losing eyebrows, last winter began losing massive amounts of hair, plus weak fingernails).
    I decided to take action on my own, and tried powdered kelp sprinkled on a cracker. I also used a salt substitute with kelp. My mood and energy level improved. The sprinkling thing became tiresome. I then went to my local high quality vitamin shop and purchased a bottle of kelp (100mg). After taking 1 per day in the AM,Two weeks ago, I decided to increase to 1 in the AM, and 1 in the PM. My nails are now growing, and seem to be stronger. Eyebrows are still sparse. My belly seems to be getting smaller… and I do have good energy.
    I am taking no other medication, except for 1 baby aspirin per day. By the way, my cholesterol level (previously in the high 200s,) has now gone down 22 points. Can’t wait to see what the doctor says about this!! I forgot to mention that drinking any alcohol, even wine, causes my thyroid gland to flutter the next day. So I have stopped drinking any form of alcohol.

  17. Ro C.

    Where did you order the saliva test from?
    Where did you get Naltrexone?
    What test did you do to see your antibodies?
    I am trying to combat menopausal symptoms eg: hot flashes, and took Estrovan. I have not eaten soy since being diagnosed with Hashimoto’s almost 9 years ago, so this supplement threw me for a loop. I gave it 28 days (amount in package) and gained almost 10 pounds! I feel bloated, my breasts seem larger. I know it was a mistake but now I have to reverse what I did. I also think my numbers were thrown in a tizzy because I also have the fuzzy thinking that is indicative to me and high TSH.

  18. Denise Jarratt

    I’ve read and heard varying information about kelp to help with hypothyroidism. I’m a little reluctant to try it as I’ve been working on balancing my thyroid for the past 6 years. I was diagnosed with Hashimoto’s Hypothyroiditis appx. 6 years ago at age 44. I wanted to stay as “natural” as possible, so decided to use Armor. I’ve been on many different doses of Armor over the years, but finally settled on 180 mg. for the past couple years. In addition, I also take Low-Dose Naltrexone to help lower my antibodies associated with Hashimoto’s.
    Over the course of 3 years I’ve lowered my antibodies from a staggering 8,830 to 1,470 (a normal antibody reading is 35 and under, so I’m still working on getting to that number). I also began using bio-identical hormone replacement therapy 3 years ago in capsule form (200 mg.) After doing everything I could think of over the past 6 years to help with the symptoms of Hashimoto’s and a hormone imbalance I was still experiencing all the annoying symptoms.
    I heard saliva testing is a more accurate way to test for a hormone imbalance, so I recently took a saliva hormone panel test. The results showed I was still in estrogen dominance, which means my hormones are not balanced, I have too much estrogen and not enough progesterone. My cortisol levels are too high, which explains the belly fat (I work-out 6 days a week and watch my diet) and I’m also suffering from Hypo-Adrenia, a non-Addison’s form of adrenal fatigue disease, which explains my lingering fatigue.
    Western medical doctors only test for Addison’s disease by way of a blood test, so unless you’re suffering from Addison’s disease, they will tell you your adrenals are fine. As a result of the saliva test I’ve switched to a cream-based bio-identical progesterone. After only one month of taking the recommended natural supplements, my TSH levels are now too high, so my medical doctor recently lowered my dose to 150 mg. of Armor.
    I’m currently taking all natural supplements to help offset the effects of estrogen dominance, to help lower my cortisol levels and to give my adrenals a boost. I’m also working on changing my eating and sleeping habits associated with adrenal fatigue After only 2 weeks of adding more progesterone and a month or so of taking supplements and changing my eating and sleeping habits, I’m already feeling my energy levels increasing and my symptoms receding.
    I’m thinking of adding kelp to my diet to help boost my thyroid even more. I will do another round of bloodwork in 3 months to test my thyroid and another saliva test in 2 months to test my hormone levels. I will let you know the results and if I think the kelp helped improve my thyroid levels.

  19. GretaT

    I started taking kelp capsules after hearing it could possibly correct the swelling of my thyroid. A biopsy didn’t show up anything but it remains swollen. Unfortunately, although I am not sure the capsules are the reason, I noticed that shortly after starting the kelp my urine has an awful odor. Could that be the reason?

  20. Debi O

    I just started using kelp.. I took the online test and I am confused cuz I have symptoms of over and under active thyroid… I am hoping this herb will help me… I have three months til I see my doc again….

  21. Sara G

    Kelp is wonderful for thyroid and just about anything for metabolic purposes. Whole Foods has a great kelp tab. I also like cod liver oil and sharks cartilage for joint mobility. Marine protein is really good for me. Try it, you will enjoy the benefits.

  22. NI

    hi there, just after some advice…
    I’m 27 and was diagnosed with hypothyroid in Oct 09. my thyroid level was 98. I was always so tired I would sleep for 15hrs and still wake up tired, was so cold that would suffer from chill blaines, my hair and eyebrows began thinning out. I was also told I was anemic and had vitamin D deficiency which made me feel worse. My immune system was so weak I was constantly ill.
    I’ve been taking 125 Levothyroxin since diagnosed and now my thyroid level is within the correct range but still feel so tired. I’ve also gained loads of weight, uk size 10 to 14. I’m trying to lose the weight but nothings working. I go gym/swimming 3/4 times a wk, cut out carbs + fizzy drinks, eat 5 smaller healthier meals but just doesn’t work. What would you suggest?
    Also I’m thinking of taking kelp but worried in case it makes my health worse…

  23. sandy

    I take 175 MCG Levothyroxin, and on my last two blood test done, it showed low. I called the doctors office, and he does not want to change the dosage at this time. I am losing my eyebrows, have a hoarseness to my voice at times, and seem to be more tired. (I don’t sleep very well). I bought a bottle of kelp, and thought I’d try taking 1 tablet a day… but now I am afraid to try this. I am now thinking of taking an all natural supplement. Very confused as what to do. I also take Lisinop-HCTZ TAB 10 – 12.5. (I am 66)
    Thank you in advance!

  24. Kara L.

    I am hypothyroid and on Armour. I do take kelp too. I got my thyroid levels correct first and then I did a few iodine patch tests to see if it picked up a deficiency. It showed I was deficient, so I started the kelp. Many people do fine with a little bit of iodine, then there are others that don’t.
    I started out by taking powdered kelp, but the problem with powdered kelp is that there are no dosages. Plus, iodine deficiency is a symptom, not a cause. There are other, more pressing headaches associated with hypothyroidism. Metabolism, for starters, which can play hell with your immune system, and also your mental health. If you look at a nurses’ guide, you’ll see that thyroid issues can lead to some chemical difficulties in brain/body day-to-day functioning.

  25. James K.

    I would check your TSH level again and see how you are doing?

  26. Jean L.

    About 4 years ago I decided to stop using the synthetic thyroid hormone doctors had prescribed for me for many years. It was a fairly low dose anyway. Also I never felt very good. I was a little overweight and my doctor said my blood pressure was pre-hypertensive. Also I was always chilly (my body temp was usually only about 97 deg, even in the late afternoon) and had very dry skin in the winter.
    I was a little worried about dropping the synthroid, but I had heard of several people who did it and felt fine afterwards. To try to boost my own thyroid gland to compensate for the loss of synthroid I started using iodized salt and started substituting distilled water for tap water to avoid the fluoride. I also started using a no fluoride toothpaste. It took about 6 mos. but then I think my thyroid gland gradually started producing more hormone. My blood pressure was normal, I was not so chilly all the time, and my body temp was usually 98 or 98.6 F.
    At the very beginning my neck seemed to swell just a bit and I was really worried I was going to get a goiter, but this subsided after a month or two. I feel great, have lost about 5 lbs without trying, and have plenty of energy. One of the main reasons I wanted to drop the thyroid pill is that I was worried about how I would get the pills if we had a major natural or unnatural disaster happen.

  27. md

    Can you please explain the iodine/thyroid connection and the thyroid/skin and nails connection? Is there a thyroid/weight control connection and will iodine help?
    I read an article that indicated fluoride and other chemicals that are added to drinking water can give a false read on thyroid test results. Apparently they are in the same classification as iodine. So a lot of people that have been diagnosed with “metabolic syndrome” may actually just need to have their thyroid “tweaked” to enable them to lose weight which in turn will lower cholesterol readings and blood pressure.
    Is any of this true? I use sea salt all the time – I can’t remember the last time I consumed iodized salt. And I am trying to keep my salt consumption to a minimum.
    I have endured eczema and dry brittle nails for years. Several different medications from a dermatologist have not helped at all – 2 different cortisone type creams, an anti-fungal cream as well as anti-fungal oral medication, antihistamines (in addition to Singulair and Clarinex that my other doctor has prescribed – and no, she didn’t think that 3 antihistamines a day was unwise) have done nothing to resolve either the itchy, dry, scaly skin or the breaking, peeling nails.
    I was desperate. A woman at my local health food store suggested I try kelp tablets to see if the extra iodine would help. After 2 weeks of taking 2 tablets a day I can report that my face no longer is dry and itchy. My nails seem to be growing, and I have lost 2 pounds for no apparent reason (no increase in activity or decrease in food consumption).

  28. Robert O.

    Presently I am taking Levothyroxine 0.125mg daily. Can I also take some Kelp with it or take Kelp alone for some trial?

  29. DP

    In 1959, I was a 19 year old nursing student at a big teaching hospital. In those days the med. students used us as part of varying research projects and took blood tests and other data. From these studies I learned I had low thyroid values. The older doctor in charge of our student health told me I was too young to be placed on thyroxin and to have it checked again in 5 years. I forgot about it completely until I was 29 and had occasion to have it drawn again. My Dr. suggested I try kelp tablets since we rarely ate fish at home, and the level was still just below normal. So I did, once a day. To my surprise I began having once a month menstrual periods! All my life I had had a period once every two or 3 months. My hands and feet weren’t freezing any more.
    Several years later, my oldest son complained to me that he was worried, at 15, because he hadn’t showed signs of puberty yet and his younger twin brothers were showing signs already at 13. I thought maybe because I had been skinny and low thyroid during his pregnancy maybe his thyroid might also need a little iodine as I had. So we gave him 1 small kelp tablet daily. In a month he began showing secondary sexual changes. Boy was he relieved! Was it the kelp or just his time? I don’t know.
    I stopped taking it many years ago when our diet became more healthful and the thyroid tests were at normal and still are. Thyroid is complicated business.

  30. sdkpak

    Great to know your experience with Kelp. I am totally amazed that Kelp could correct Thyroid values and would like to know more if you can share. I currently am thinking of taking up Kelp, but fear of overdosing is stopping me.

    • BP

      I don’t use iodized salt, so I take a daily kelp supplement with 225 micrograms (mcg) of iodine. According to the NIH, a normal adult needs 150 mcg daily, but up to 1100 mcg is considered safe (This is the “Tolerable Upper Intake” level). When researching supplements, I saw several with considerably more iodine than that! Since getting too much iodine can actually cause thyroid problems, make sure you do your research and don’t overdo supplementation. The NIH data is here:

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