Unclear
Colloidal silver
silver particles in water, sold as a supplement. Claimed cures.
Safety: It can permanently turn the skin blue-gray (argyria), and it reduces the absorption of some antibiotics and thyroid medicine.
- Verdict
- UnclearThere isn't enough human evidence to say either way.
- How sure
- Rung 1 · UnprovenLab or animal data only, or never directly tested in people.
The rung shows how sure the science is, not how big the effect is. How to read these ratings
Cancers affected
None studied
What the evidence shows
Silver has no known use in the body when swallowed. The FDA says colloidal silver isn't safe or effective for treating any disease, and the FDA and FTC have acted against companies making false claims.
What to do
Don't take it. Tell your doctor if you do, because it can stop some medicines working.
Sources
To take it to your doctor, print this page.
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Related
Every myth and exposure we rated, or follow one cancer step by step: breast cancer, colorectal cancer, lung cancer and prostate cancer.