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Thorne Research, Thyrocsin, Thyroid Cofactors, 120 Veggie Caps

Thorne Research, Thyrocsin, Thyroid Cofactors, 120 Veggie Caps

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In Stock
  • Expiration Date: Jan 2018
  • Shipping Weight:
    0.3 lbs
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  • Product Code: THR-78401
  • UPC Code: 693749784012
  • Package Quantity: 120 Veggie Caps
  • Dimensions:
    2.2 x 2.2 x 4.4 in, 0.25 lbs
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Save $4.01 when you purchase these items today for only $32.14
Total: $36.15
Combo Discount: - $4.01
Together: $32.14

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Product Overview


  • Dietary Supplement
  • Hypoallergenic
  • For Nutritional Support of Thyroid Function
  • Contains Nutrients and Botanicals That Enhance T4 Production
  • Provides Key Nutrients for Peripheral Conversion of T4 to T3
  • Helps Optimize Metabolism
  • Unique, Non-Glandular Formulation Available Only from Thorne Research

The hormones thyroxine (T4) and triiodothyronine (T3) are produced by the thyroid gland. These hormones are essential to the proper development of cells in the body. Thyroid hormones regulate the metabolism of proteins, fats, and carbohydrates, affecting how these compounds produce energy. Individual thyroid hormones have important functions in the body; for example, T4 supports cardiac output, heart rate, respiratory rate, and basal metabolic rate (BMR). A low BMR may cause one to be fatigued, chilly, and have trouble losing weight.

Thyrocsin provides supportive nutrients for a healthy thyroid gland. Not only does Thyrocsin support healthy thyroid function, it also provides nutrients necessary for conversion of T4 to T3 in the tissues outside the thyroid gland.

Iodine is necessary for formation of T4, while L-tyrosine is a necessary component of both T4 and T3 formation. Animal studies indicate the Ayurvedic botanical ashwagandha can increase T4 concentrations. Several nutrients are also necessary for conversion of T4 to T3, including the minerals selenium, zinc, and copper. Thyrocsin contains vitamin B12 because its insufficiency appears to interfere with the activity of thyroid hormones. Conversion of T4 to T3 can be inhibited by heavy metal toxicity and lipid peroxidation; the antioxidant vitamins C and E can counterbalance this inhibition.

Thyroid hormones are involved with metabolism throughout the body. Thus, a deficiency or excess of thyroid hormones can have far-reaching effects. High cortisol levels can interfere with thyroid function, resulting in low T4 or poor conversion of T4 to the active form, T3. Nutrients that support normal levels of cortisol may be of benefit for this population.

Suggested Use

Take 2 capsules two times daily or as recommended by a health-care practitioner.

Other Ingredients

Hypromellose (derived from cellulose) capsule, leucine, silicon dioxide.

This product is contraindicated in an individual with a history of hypersensitivity to any of its ingredients.

This product does not contain wheat, gluten, corn, yeast, soy, egg, dairy products, or artificial colors, sweeteners, or flavors. This product also does not contain lactose, palmitic acid, or magnesium, calcium, or vegetable stearates.

Iodine may occasionally cause an allergic reaction in some individuals.


Tamper Evident: Use only if bottle is sealed. Store tightly sealed in a cool, dry place.

If pregnant, nursing, or trying to conceive, consult your health-care practitioner before using this product.

Supplement Facts
Serving Size: Two Capsules
Servings Per Container: 60
  Amount Per Serving %Daily Value
Vitamin C (as Ascorbic Acid) 200 mg 334%
Vitamin E (as d-Alpha Tocopheryl) 100 IU 334%
Vitamin B12 (as Methylcobalamin) 100 mcg 1,666%
Iodine (as Potassium Iodide) 225 mcg 150%
Zinc (as Zinc Picolinate) 5 mg 33%
Selenium (as Selenium Picolinate) 100 mcg 143%
Copper (as Copper Picolinate) 500 mcg 25%
L-Tyrosine 500 mg *
Ashwagandha extract (root) (Withania somnifera) 150 mg *
*Daily Value (DV) not established.
iHerb Customer Reviews

Thyroid health

Posted by 5099128245360572303 on May 05, 2017 | Verified Purchase

This product supports my thyroid along with my thyroid medicine. Was recommended by my doctor and I think it has kept my thyroid healthier.

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Actually effective

Posted by Reviewer2423343 on Apr 28, 2017 | Verified Purchase

It seems to work

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update, it is working!

Posted by 4852656070965980049 on May 05, 2017 | Verified Purchase

I was put on thyroid meds years ago, but I decided stop taking it because I didn't like the way I felt. My thyroid levels were borderline, and I have always had the symptoms of low thyroid function. Everyone in my family is on some for of meds or their thyroid as well. I have done a lot of research on the thyroid, and I have learned that it is actually an autoimmune problem. I can't go into detail, but if things are not right with your gut etc, your thyroid will be attacked and will not work like it should. Sooooo, I didn't want to go on meds and decided to try this for myself and my daughter. She has DS and always had low thyroid function. Overall, I feel that these supplements are helping me and my daughter. I feel better, and she said that she feels great! Not as tired all of the time. She is very high functioning for a teen with Down's, or "up's" as she calls it lol. I will have to see overtime since it has only been a few weeks. My daughter is going to have blood work done, and I will update then. I will be ordering this product again... Update/5/5/17: My daughter had blood work done which was recommended by the Endocrinologist. I told her that my daughter was taking Thyrocsin, and she was a bit skeptical, which I expected and said she would probably need medication because of her past results, and the fact that individuals with Down Syndrome almost always have thyroid issues. Sooooo, I got the results after she has been on Thyrocsin for awhile, and the Dr said her levels were great! I recall her being very low in the past and needing the meds, but I took her off because her heart was beating out of her chest even when the Dr said she was on the right dosage. Everything is great, and the doc said test her once a year, but no meds needed! :-)

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Amazing - a life saver!

Posted by 5205679328919602852 on Feb 23, 2017 | Verified Purchase

I had suspected I was hypothyroid for many years but GP tests (after I pushed for it) came back showing levels in the normal range but like most of us I know my body and knew it wasn't right. I have always been a bit overweight, could sleep all day and night, depression and thin hair are also symptoms and I had developed brain fog and poor concentration. I felt I was falling apart and the depression meds just numbed me. I did a lot of research and came across Thyrocsin after trying liquid iodine drops which were a bit unpredictable. I noticed a difference immediately and thought I was imagining it! I was more alert and upbeat, I could feel the fog lifting and I felt awake for the first time in my life and this has continued to the extent I no longer need any depression medication and I am finally losing the extra weight from my middle that no amount of diet of exercise could shift. I wish I had found it sooner. Brilliant speedy delivery to the UK. It was here 2 days after ordering. Just to note for UK buyers, customs duty is payable so be prepared for an additional cost from the courier.

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New Product for my daughter who is 9yrs

Posted by 5163288688297141300 on Feb 21, 2017 | Verified Purchase

My daughter has Hypothyroidism. I have taken her off synthetic medication and trialling her naturally. She hasn't really been on this product long enough for me to say whether or not it is good or not. Time will tell. On the plus side. She hasn't had any side effects at all.

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