TopicsSupplements and minerals
Selenium
For nutrient support for thyroid autoimmunity
A promising idea, with a smaller group behind it so far.
Selenium may help thyroid health, but individual needs and soil content vary widely.
Who is behind it
Voices including a nutritional sciences PhD, a licensed acupuncturist and clinician-educator and a registered nutritional therapist.
How strong the research is
Well studied in published research, as well as in practice.
In their words
“If you're over 120 for your plasma selenium, 200 micrograms per day is definitely too much.”
a nutritional sciences PhD
Selenium deficiency leads to thyroid cell damage, inflammation, and impaired control of thyroid hormone production.
Selenium alongside magnesium helped all women reach optimal levels and conceive within 8 months in one study.
a certified naturopathsponsored
With care
Some of the minds attach conditions. These are worth reading before you begin.
People with Hashimoto's and antibody production may require slightly higher selenium intake, but supplementation should not be perpetual or at high doses due to toxicity risks.
Two Brazil nuts provide sufficient selenium, but caution not to eat a handful as that is too much.
Selenium is included as a foundational supplement to support health related to infections and liver/gallbladder function.
Talk it through
Entrain shows what the experts teach, so you can make better decisions with your own clinician. It does not diagnose or prescribe. If something is worrying you, start there.
How this reading was made
Every line here comes from a doctor, scientist or coach speaking publicly, and links to the moment they said it. Entrain listens for where independent experts arrive at the same place on their own, and shows where they part ways. Well studied in published research, as well as in practice.
Some statements come from sponsored segments or people speaking about their own products. They are marked where they appear and count for less. Last refreshed 23 September 2026.
The research beneath it
- Supplementation with Selenium and Coenzyme Q10 Reduces Cardiovascular Mortality in Elderly with Low Selenium Status. A Secondary Analysis of a Randomised Clinical Trial.PloS one, 2016
- Foods, fortificants, and supplements: Where do Americans get their nutrients?The Journal of nutrition, 2011
- Effects of long-term selenium supplementation on the incidence of type 2 diabetes: a randomized trial.Annals of internal medicine, 2007
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