Thyroid Hormones T4, T3, rT3 & Selenium
Selenium is an important mineral and an essential component of various enzymes and proteins called selenoproteins, which helps to make DNA and protect against cell damage and infections; these proteins are also involved in reproduction and the metabolism of thyroid hormones.
Your thyroid gland produces two main hormones: triiodothyronine (T3) and thyroxine (T4). These hormones travel through your bloodstream and reach nearly every cell in your body.
In order for the thyroid gland to work properly we need the thyroid hormone T4 to revert to T3 in its active form. In some cases, T4 does not convert into the active form of T3 but into rT3.
If you’re experiencing chronic stress, depression, brain fog, anxiety, weight fluctuations etc it is advised to also check (rT3).
Below you can also observe factors that contribute to the production and conversion of the hormones:
How does selenium help with the reversion of T4 to T3 in its active form?
The production of thyroid hormones requires optimal levels of two essential trace elements: iodine and selenium. Neither is made by the human body, so they must be acquired either through food or supplementation.
Selenium deficiency alone typically does not lead to disease, however it can contribute to fatigue, brain fog, a weakened immune system, hair loss, muscle weakness and infertility. A simple blood test is all it takes to either confirm or eliminate selenium deficiency as a cause of those symptoms.
What is the best source of selenium?
Selenium is deficient in many soils as fertilizers can make selenium unavailable in the soil. It is difficult to get selenium from plants and animals.
The amount of selenium in different foods depends on the amount of selenium in the soil where the food was grown. Rain, evaporation, pesticides, and pH levels can all affect selenium levels in soil. That makes selenium deficiency more common in certain parts of the world.
Regardless of where you live and the type of food that contains selenium , certain factors can make it harder for your body to absorb selenium.
How much selenium should I consume?
Too little selenium can cause health problems but too much selenium can also be toxic. Based on the National Institutes of Health the daily recommended amount of selenium — for those over the age of 14 — is 55 mcg /daily.
While women who are pregnant or lactating need up to 60 mcg of selenium per day.
Eating 1 Brazilian nut per day is a good amount for selenium intake.
- Brazil nuts -1 Brazilian nut contains between 68 to 91 (mcg)
- Fish — Tuna contains about 92 (mcg) of selenium per 3 ounces (oz) or 85 (g)
- Eggs — One hard-boiled egg provides about 20 mcg
- Baked beans — cup of baked beans and you’ll get about 13 mcg
- Mushrooms — 100-gram serving have 12 mcg of selenium
- Spinach — one cup serves 11 mcg of selenium
https://www.healthline.com/health/selenium-foods
https://www.drberg.com/blog/eat-one-brazil-nut-each-dayhttps://www.verywellhealth.com/reverse-t3-thyroid-hormone-overview-3233184
https://medcraveonline.com/JNHFE/brazil-nuts-and-thyroid-glandnbsp.html
https://bostondirecthealth.com/thyroid-testing-why-you-should-check-your-t3-and-reverse-t3/
https://pubmed.ncbi.nlm.nih.gov/26545554/
https://link.springer.com/article/10.1007/s42000-020-00173-2
https://www.researchgate.net/figure/Factors-that-Affect-Thyroid-Function-The-Institute-for-Functional-Medicine-2014_fig1_321145710
https://www.medicalnewstoday.com/articles/foods-with-selenium#why-we-need-selenium
