Expert Advice

Selenium Rich Foods for Hypothyroidism

Acella Pharmaceuticals, LLC., is partnering with Lindy Ford, RD, LDN to bring greater awareness to the importance of thyroid care and education. This post is sponsored by Acella Pharmaceuticals and should not be construed as medical advice. Please talk to your doctor about your individual medical situation.

Selenium plays a crucial role in thyroid health, improves symptoms of depression, repairs DNA, and strengthens the immune system.1

Selenium is an essential mineral that can only be obtained through diet. Selenium deficiency has been associated with a thyroid condition called Hashimoto’s thyroiditis, a type of hypothyroidism in which the immune system attacks the thyroid gland.2

The thyroid gland produces two important hormones called triiodothyronine and thyroxine (T3 and T4). Selenium aids in the activation of T4, the storage form of the thyroid hormone that gets converted to the active form of T3.3

This activation of T4 to T3 enables the body to use the thyroid hormone for a wide range of metabolic functions.

There are two reasons why selenium deficiency is on the rise. The amount of selenium in food depends on the selenium concentration of the soil. This varies from region to region.4

Probably the biggest problem with deficiency is poor digestive or gut health. Even when adequate amounts of selenium are present in the diet, the mineral is not absorbed optimally. This is why I say to my patients daily, “You are not what you eat, you are what you absorb.”

Gut health is essential, but we still want to make sure we are getting an adequate amount of this crucial mineral. Excessive amounts are also detrimental.


1. Brazil Nuts

These nuts contain the highest amount of selenium. One single nut has around 68 to 96 mcg (more than 100 percent of the daily value). A 1-ounce serving contains 537 mcg of selenium.

We need to approach Brazil nuts with caution. The National Institutes of Health warns consumers that too many Brazil nuts can cause the upper limit for selenium to be exceeded.5 That is why I recommend no more than one or two Brazil nuts per day.

2. Oysters

Most shellfish contain significant amounts of selenium, but oysters reign supreme out of all of them. They also contain a good amount of zinc, vitamin B12, and copper.

3. Yellowfin Tuna

All tuna contains significant amounts of selenium, but yellowfin is the highest. The only caveat is that yellowfin is relatively high in mercury and must be limited.

Tuna is also an excellent source of omega-3 fatty acids. Most of us don’t get optimal amounts of this crucial nutrient. Omega-3s are beneficial to thyroid health. Limit yellowfin tuna to one serving per week.

4. Mussels

This seafood is not far behind oysters in selenium content. Mussels are relatively inexpensive and are an excellent source of B vitamins, omega-3s, manganese, iron, and zinc.

5. Sunflower Seeds

Other than Brazil nuts, sunflower seeds are the best plant-based source of selenium. They don’t have to be limited. A 1-ounce serving contains about 23 mcg. Sunflower seeds also contain a significant amount of manganese, vitamin E, fiber, and copper.

I do sometimes supplement selenium in individuals with hypothyroidism and low dietary intake. Please consult with a health care practitioner before using supplementation.

Did you get your selenium today? Make sure you are optimizing your gut health for better absorption of this crucial mineral and include these selenium-rich foods in your diet.

Check out my YouTube Gut Health Series: 

When your thyroid works more efficiently, your body rewards you.

Selenium Foods for Thyroid Diet

Important Risk Information

Drugs with thyroid hormone activity, alone or together with other therapeutic agents, have been used for the treatment of obesity. In euthyroid patients, doses within the range of daily hormonal requirements are ineffective for weight reduction. Larger doses may produce serious or even life-threatening manifestations of toxicity, particularly when given in association with sympathomimetic amines such as those used for their anorectic effects.
  • NP Thyroid® is contraindicated in patients with uncorrected adrenal insufficiency, untreated thyrotoxicosis, and hypersensitivity to any component of the product.
  • In the elderly and in patients with cardiovascular disease, NP Thyroid® should be used with greater caution than younger patients or those without cardiovascular disease.
  • Use of NP Thyroid® in patients with diabetes mellitus or adrenal cortical insufficiency may worsen the intensity of their symptoms.
  • The therapy of myxedema coma requires simultaneous administration of glucocorticoids.
  • Concomitant use of NP Thyroid® with oral anticoagulants alters the sensitivity of oral anticoagulants. Prothrombin time should be closely monitored in thyroid-treated patients on oral anticoagulants.
  • In infants, excessive doses of NP Thyroid® may produce craniosynostosis.
  • Partial loss of hair may be experienced by children in the first few months of therapy but is usually transient.
  • Adverse reactions associated with NP Thyroid® therapy are primarily those of hyperthyroidism due to therapeutic overdosage.
  • Many drugs and some laboratory tests may alter the therapeutic response to NP Thyroid®. In addition, thyroid hormones and thyroid status have varied effects on the pharmacokinetics and actions of other drugs. Administer at least 4 hours before or after drugs that are known to interfere with absorption. Evaluate the need for dose adjustments when regularly administering within one hour of certain foods that may affect absorption.
  • NP Thyroid® should not be discontinued during pregnancy, and hypothyroidism diagnosed during pregnancy should be promptly treated.


NP Thyroid® (thyroid tablets, USP) is a prescription medicine that is used to treat a condition called hypothyroidism from any cause, except for cases of temporary hypothyroidism, which is usually associated with an inflammation of the thyroid (thyroiditis). It is meant to replace or supplement a hormone that is usually made by your thyroid gland.

NP Thyroid® is also used in the treatment and prevention of normal functioning thyroid goiters, such as thyroid nodules, Hashimoto’s thyroiditis, multinodular goiter, and in the management of thyroid cancer.