Equipment Reference
NOW Foods
NOW Foods Selenium 200 mcg
NOW Foods Selenium 200 mcg review — yeast-free L-selenomethionine capsules for thyroid conversion and glutathione enzymes (and why 1 capsule is plenty).
L-selenomethionine — one capsule, not a second, and not on top of Brazil nuts
NOW’s 200 mcg L-selenomethionine is the common Amazon selenium. The adult upper limit is 400 mcg/day from all sources. One capsule plus a high-selenium multi plus a handful of Brazil nuts is how people overshoot. Thyroid context belongs with a clinician. See the selenium guide. This is not a cancer protocol.
Health Disclaimer
This content is for general informational and educational purposes only. It is not medical advice, diagnosis, or treatment. Consult a qualified healthcare provider before starting any supplement, peptide, or health protocol. Read our full health disclaimer.
Typical price: $12 – $20 USD / 300 veg capsules
How It Works
Selenium is required for glutathione peroxidases and thyroid hormone conversion. Deficiency is the interesting problem. Excess is hair loss, nails, and garlic breath — selenosis — not ‘more antioxidant.’
200 mcg, Once
RDA is 55 mcg. 200 mcg is a high supplement dose still under the 400 mcg UL — until food is counted.
Selenomethionine
The organic form NOW uses here. Do not add a yeast-selenium on top.
Brazil Nuts
One nut can rival a capsule, and the next nut can triple it. Pick nuts or the bottle, not both daily.
What You'll Experience
If Diet Is Low
WeeksYou may feel nothing. That is fine. The point is not a buzz.
If You Double It
StopTwo capsules plus nuts is not a protocol. Stop and tell a clinician if nails or hair change.
Benefits
Known Form
Moderate EvidenceL-selenomethionine, 200 mcg, labeled.
Cheap
Moderate Evidence300 count is a long bottle. You still only need one a day, if any.
Risks & Considerations
Upper Limit
high risk400 mcg/day from all sources. Stacking is the failure mode.
Thyroid
medium riskSelenium can matter in thyroid disease. That is a clinician, not a second capsule.
Community Reviews
Synthesized consensus from Reddit, forums, and expert sources.
NOW selenium is a frequent cheap bottle. Smart comments mention the 400 mcg ceiling. Brazil-nut stackers are the cautionary reviews.
- ·200 mcg
- ·Once daily
- ·Not with nuts
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Read guideLast updated: 2026-09-22 · Informational only. Not medical advice. Health disclaimer.