Nutrient Depletions In Hashimoto's V: Zinc Zinc is an essential element to our well-being.


Zinc is an essential element to our well-being. Zinc acts as a catalyst in about 100 different enzyme reactions required by our body, and is involved in DNA synthesis, immune function, protein synthesis, and cell division. It is required for proper sense of taste and smell, detoxification, wound healing, and thyroid function. Zinc is not stored in the body, thus a daily intake of zinc is required to maintain sufficient levels.

One in four individuals in the general population may be zinc deficient, and most people with hypothyroidism are in fact zinc deficient. Zinc deficiency prevents the conversion of T4 into the active T3 version.  This perpetuates the Hashimoto's vicious cycle by a slowed metabolism of proteins. 

Zinc is also needed to form TSH, and may become depleted in those with hypothyroidism who are constantly producing more TSH.

Zinc deficiency has also been associated with increased intestinal permeability and susceptibility to infections as well as reduced detoxification of bacterial toxins.

Oysters have the highest concentration of zinc, but they are not something most people would enjoy eating every day. Beef, liver, pork, lobster, and chicken are the next best sources of zinc, as it is easiest to extract zinc from meat compared with non-meat sources. Thus, vegetarians also have an increased risk of zinc deficiency.

Absorption of zinc may be impaired by damage from intestinal disease such as celiac disease and other malabsorption syndromes. Phytates found in grains, legumes, nuts and seeds can bind zinc and prevent its absorption when eaten alongside zinc containing foods. Taking iron supplements in conjunction with meals may also prevent the absorption of zinc from food.

Zinc deficiency can show up on a liver function blood test as low alkaline phosphatase levels. The importance of alkaline phosphatase will be discussed in further detail...

In order to address deficiency, zinc supplementation may be utilized, with doses of no more than 30 mg per day. This is because Zinc supplementation above 40 mg may cause a depletion in copper levels. If choosing to take zinc, one should also take a copper supplement. Usually 1.5 mg–3 mg of copper should be sufficient. (General recommendations are to take 1 mg of copper for every 15 mg of zinc).

Caution: Zinc can cause depletion in copper and iron. Fifty milligrams of zinc given over ten weeks impaired both iron and copper absorption in one study.

Symptoms of copper deficiency are: anemia not responsive to iron supplementation, trouble with walking and balance, fatigue, and light headedness.

Not all supplemental zinc formulations are created equally...I prefer the Zinc Picolinate version because it is absorbed better. 
To ensure proper absorption, Zinc supplements should be taken with food. 

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NOTE: These statements have not been evaluated by the Food and Drug Administration. The products discussed are not intended to diagnose, treat, cure, or prevent any disease.

Your Thyroid Pharmacist,
Dr. Izabella Wentz, Pharm D.

PS. You can also download a free Thyroid Diet Guide, 10 Thyroid friendly recipes, and the Nutrient Depletions and Digestion chapter for free by going to You will also receive occasional updates about new research, resources, giveaways and helpful information.  

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  1. Daher R, Yazbeck T, Bou Jaoude J, Abboud B. Consequences of dysthyroidism on the digestive tract and viscera. World J Gastroenterol 2009; 15(23): 2834-2838 Available from: URL:
  2. Wada L, King JC. Effect of low zinc intakes on basal metabolic rate, thyroid 
hormones and protein utilization in adult men. J Nutr 1986;116:1045–53. 


Archived Comments

This is very timely as I was just told my zinc is very low! I'm a vegan with Hashi's, so I guess that's a double whammy. I've been taking a multi which contains 100% of the RDA of zinc, but that clearly wasn't enough for me. I'm glad to have learned about needing t watch my copper while supplementing with zinc. Thank for the info!
Thanks for writing Geralyn, Often the zinc in the multi's doesn't get absorbed as well...
Thanks so much for this post Dr. Wentz! Can you comment on pyroluria? I'm wondering if this might not be a possible "root cause" of hashimoto's since it is a genetic condition causing zinc deficiency and since zinc is so vital for the thyroid. Also, would taking more than 30 mg of zinc be a good thing for someone with pyroluria in order to draw excess copper out of the body? I have hashimoto's and I'm being tested for pyroluria. Thanks!
I found out I'm severely copper toxic through Genova diagnostics heavy metal urine testing with dmsa provocation... Hair tissue mineral analysis,...and blood testing copper, zinc serum, ceruloplasm and total body histamine... In serum if zinc is at 1.0 then copper should be no higher than . 7 in ratio.... My copper was double my zinc.... Once your copper poisoned so much your estrogen receptors shut down.... My estrogen and testosterone is extremely low...furthermore while I'm copper toxic I'm also copper deficient due to biounavailability This has been a nightmare 3 year's for me... Seeing a Dr trained in methylation soon to help me sort it all out.... I encourage every woman to get tested because it accounts for just about every illness known to man

Dear Dr. Weintz, I love all the amazing information in your book! So much to learn. My question is regarding Betaine Pepsin vs. Zinc supplements. Since the former helps you extract zinc, why would you also need to add an actual zinc supplement? If one does take zinc, should it be permanent or for a short while, since it has side effects? Thanks!