Evidence brief · Supplement
Selenium for Prostate cancer prevention
Evidence grade D — SELECT null, possible harm
- Overall grade
- Grade D
- Last revised
- 1
- graded outcome
- 0
- references listed
Assembled by the app from other entries in this library. It adds no evidence of its own — follow the links to the entries it draws on.
1 at grade D — 1 graded row
What is known
Each outcome with its grade (how strong the evidence is, A to D), the size of the effect where the entry records one, and how often studies agree.
- Prostate cancer preventionEvidence grade D
SELECT null, possible harm
Trivialhigh
What is uncertain
Read off the same rows as above. Nothing here is added that the entry does not itself record.
- Thin evidence: Prostate cancer prevention (grade D).
The evidence in words
The verdict
For prostate cancer prevention, Selenium earns evidence grade D (trivial effect, high consistency) — the evidence does not support the claim. SELECT null, possible harm
How it might work
Selenoproteins recycle antioxidants and convert thyroxine (T4) to active T3, tying selenium to both oxidative defense and thyroid function.
How to use it
A couple of Brazil nuts or a modest multivitamin dose covers requirements. Therapeutic use in thyroid disease belongs under a clinician; avoid standalone high-dose selenium.
Safety & cautions
Toxic in excess: hair and nail loss, GI and neurological effects. The gap between adequate and harmful is smaller than for most nutrients.
Bottom line
Get enough (a Brazil nut or two), avoid megadosing. The 'antioxidant prevents cancer' pitch failed in trials and high intakes carry real downsides.
How it is used
As the entry records it, from the studies it summarises. Not a recommendation for you — doses that suit a trial population may not suit you.
- Adequacy
- Modest dose or 1–2 Brazil nuts; avoid high-dose standalone.
Goes with
- SeleniumRead the full Selenium monographEvidence grade C
Related reading
Entries that share this one's tags or conditions.
- Selenium for Autoimmune thyroiditis antibodiesEvidence grade C — Under careEvidence grade C
- Selenium: dosage and how to take itModest dose or 1–2 Brazil nuts; avoid high-dose standalone.Evidence grade C
- Selenium: side effects, safety & interactionsToxic in excess: hair and nail loss, GI and neurological effects. The gap between adequate and harmful is smaller than fEvidence grade C
- Astaxanthin for Exercise recoveryEvidence grade C — PreliminaryEvidence grade C
Sources
This entry lists no references of its own — it is assembled from the entries it links to, whose sources are on their pages.
Last revised . A grade is this entry's reading of the evidence, not medical advice.