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NOW Foods Selenium 200 mcg bottle
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NOW Foods Selenium 200 mcg Review

NOW Foods Selenium 200 mcg is an essential trace mineral incorporated into selenoproteins, which are vital for antioxidant defense, thyroid hormone metabolism, and immune function.

Product Focus: Thyroid HealthAlso graded for:Eye HealthAlso covers:HormonesImmune system
Tier ⓘ
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Members see this product's tier and why. Tiers run from 1, the strongest evidence, to 5. How we grade →
Evidence ⓘ
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How strongly the evidence says this product works: human studies count most, then real reviews, then our biohacker panel.
Positive Reviews
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Biohacker Mentions
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Cost per month
$2
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Study, Trial or Testing Result Summary

MembersHuman studies

This product gives 200 micrograms of selenium a day as selenomethionine, a dose that matches what thyroid studies used. The shows up mainly in people with autoimmune thyroid disease, such as Hashimoto thyroiditis. …

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Review Totals and Summary

Members21,367 reviews
21,367 reviews · IHerb 21,268 · Walmart 60 · Naturitas 20 · Swanson 19

Reviews for NOW Foods Selenium 200 mcg are , with users expressing levels of and noting noticeable after incorporating the supplement into their daily routine. A number of reviewers from iHerb, Walmart, and other sites mention how easy the tablets are to swallow and appreciate their taste, which makes them convenient for regular use. …

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Biohacker Summary

MembersWhat our biohacker panel says

Nearly of the panel selenium, and eight of the nine who spoke about it gave a latest position of , while one was . The common reason is thyroid , especially the body convert thyroid hormone and supporting people with autoimmune thyroid , and others cite antioxidant and detox support, male fertility, hair , and immune . …

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RAL Summary

MembersThe tier and why

One review judged the evidence too for routine use. …

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More Details

MembersBody systems · Combine with · Possible side effects

Body systems: Endocrine system, Immune system. Combine with and possible side are for members.

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Supplement Facts

Selenium 200 mcg
Supplement Facts
Serving Size 1 Veg Capsule
Servings Per Container 180
Amount Per Serving% Daily Value
Selenium (elemental) (from 40 mg L-Selenomethionine)200 mcg364%

Directions: Take 1 capsule daily with a meal.

Barcode (UPC) 733739014863 · Label source: Swanson · Report a label change

Where to Buy

NOW Foods · iHerb · Swanson
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We sell no supplements. Prices change; check the store.

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Our articles on this subject

Graded October 23, 2026 by the Reverse Age Lab evidence engine, from human studies, real reviews and our biohacker panel. How we grade. Is this medical advice? No. Rala organizes the published evidence; go over any change with your doctor, especially if you take meds.