Is ingesting colloidal silver helpful for any condition and is it safe to use?

Answer:

What are the health benefits of colloidal silver?

Colloidal silver (a solution with silver particles) has antiseptic (disinfectant) activity, and, for this reason, has been promoted for a wide number of uses, from treating sinus infections and ear infections to boosting the immune system. It has also been promoted to help treat diabetes, arthritis, thyroid conditions, and even cancer. However, there is no clinically-proven benefit from ingesting colloidal silver, and there are potential risks.

What problems can be caused by ingesting colloidal silver?

Long-term ingestion of colloidal silver can cause "blue man syndrome," or generalized argyria, a permanent gray or blue discoloration of the skin. Rarely, chronic consumption of colloidal silver has been associated with the development of seizures; in one case, this led to coma and death (Mirsattari, Neurology 2004; Stepien, Ann Clin Biochem 2009). Colloidal silver can also cause permanent discoloration of nails. A 79-year-old man developed permanent blue-gray discoloration of his fingernails (also referred to as azure lunula, a subtype of generalized argyria) after regularly consuming colloidal silver (30 ppm i.e., parts per million) mixed with a liquid silver as a supplement. The nail discoloration remained, but did not worsen, six months after he stopped supplementation as advised by his physician. Be aware that blue-gray discoloration of the nails can also result from conditions such as lead or mercury poisoning, cyanotic heart disease, and melanoma, so it's important to consult with a physician to help to determine the cause and proper treatment (Slater, Cureus 2022).

Consuming colloidal silver can also cause a grayish discoloration of the white portion of the eyes (called argyrosis, a subtype of argyria) and affect tests used to examine the eyes including fluorescein angiography optical coherence tomography (OCT), as reported for a man who had consumed colloidal silver for approximately 8 years (Docherty, Can J Ophthalmol 2019).

Long-term use of an oral colloidal silver supplement is suspected to have caused bone marrow damage and contributed to the development of cancer of the blood and bone marrow (acute myeloid leukemia, or AML) in a 79-year-old man who had been taking this supplement for more than ten years. His blood silver level was found to be approximately five times the maximum normal level. The man died due to progressive respiratory failure (a complication of AML) and pulmonary embolism. His physicians at a UCLA Hematology-Oncology clinic noted that there is evidence that silver may cause changes in bone marrow and blood cells, and has been shown to promote tumor growth in laboratory studies. They also speculated that colloidal silver may have altered the "normal bacterial flora" in the man, making him more susceptible to respiratory infection (Keung, J Oncol Pharm Pract 2019).

A 19-year-old woman who consumed colloidal silver for one month for "internal cleansing" developed inflammation of the small blood vessels in the skin (leukocytoclastic vasculitis) that presented as a severe, itchy rash and fever. Her condition slowly improved over a 5-day stay in the hospital where she received treatment and stopped taking the silver (Mohan, Am J Case Rep 2019).

Colloidal silver may cause fetal abnormalities if taken during pregnancy (Fung, J Toxicol Clin Toxicol 1996).

Quality concerns with colloidal silver products

Tests of 16 colloidal silver products (brand names not provided) in the U.S. found that 10 of 13 that listed an amount of colloidal silver did not contain within 20% of that amount -- three of which contained only 0.5% to 15% of what was listed. Taking the dose recommended on products would yield from 5.6 mcg and 961 mcg of silver per day — an enormous range. These were all far below the level associated with acute adverse effects but, as noted by the researchers, there are potential risks associated with chronic ingestion of even small amounts of silver, including changes the microbial balance in the gut, and possible toxicity to the lining of the small intestine. Some products also contained nanoparticles of silver, which, due to their small size, may be more toxic than larger silver particles to the cardiovascular system, and, if inhaled (as from a spray) may have inflammatory effects on tissue in the nose and lung (Rogers, Sci Total Environ 2018).

The bottom line:

There is no clinical evidence that colloidal silver supplements effectively treat infections, diabetes, arthritis, thyroid conditions or cancer. Furthermore, colloidal silver can cause permanent blue discoloration of the skin nails, eyes, as well as cause vasculitis. Rarely, seizures have been reported. Pregnant women should not use colloidal silver.