Q: Is it beneficialand safeto take colloidal silver?
A: No on both counts. The Food and Drug Administration (FDA) banned the use of colloidal silver and silver salts in over-the-counter drugs in 1999, declaring them neither safe nor effective. Dietary supplements containing them can still be sold, however, if they don't make medical claims. The government has taken action against many companies that do make such claims, but that hasn't put an end to the products.
Colloidal silver is a suspension of fine silver particles, usually marketed as a liquid or as lozenges. Though it's touted as a cure-all for everything from acne and arthritis to herpes and cancer, there's no evidence that colloidal silver has any health benefits.
In addition to dietary supplements, colloidal silver products also are available in suspensions that can be applied to the skin. Silver was used medicinally before less-toxic drugs were developed and there are still a few approved topical uses for it. But silver is not an essential mineral and it has no known function in the body.
Colloidal silver can, on the other hand, have side effects. Silver particles can accumulate in tissues and organs and turn your skin, nails and the whites of your eyes a harmless, but permanent, blue-gray color. Of more concern, colloidal silver can damage the kidneys and nervous system and have other serious effects. It may cause seizures and also can interfere with medications, including some antibiotics and certain thyroid drugs. Don't take colloidal silver or silver salts.
By the way: There's also no credible evidence to back up the farfetched claims made for other "colloidal mineral" products, which typically include a mix of minerals, amino acids, enzymes and other substances.
Source: Adapted from an article originally published in The University of California, Berkeley Wellness Letter (September 2011)