'Open up the conversation' about dietary supplements to prevent colloidal silver ingestion

Key takeaways:

• Ingesting colloidal silver is unsafe and can lead to serious health effects, like argyria.
• Ask patients about dietary supplement use to help prevent adverse events from colloidal silver ingestion, experts said.

Ingesting colloidal silver supplements is popular but unsafe and, in excess, can lead to a patient’s skin permanently turning blue, according to experts.

Colloidal silver is made up of miniscule particles of silver that are suspended in liquid, according to Sekai Chideya, MD, MPH, program director of clinical research at NIH’s National Center for Complementary and Integrative Health.

“It's taken as a dietary supplement, often promoted online for its supposed health benefits, though evidence supporting these claims is lacking,” Chideya told Healio. “There is no established ‘safe’ level of colloidal silver.”

The FDA has previously issued warnings that colloidal silver is not effective or safe for the treatment of any condition, Chideya said. The FDA and Federal Trade Commission have also taken action against some companies for their misleading claims about colloidal silver, she added.

However, the 1994 Dietary Supplement Health and Education Act means that products marketed as dietary supplements are not as heavily regulated by the FDA. Colloidal silver supplements are currently available for purchase, with sellers claiming it can boost immune function and potentially offer other health benefits. One such product — posited as safe and effective for adults and children aged at least 4 years — has more than 37,900 ratings on a major retailer’s website, averaging 4.7 stars, and is listed as a number one best seller.

“It’s marketing,” Lewis Nelson, MD, professor and chair of the emergency medicine department and chief of the division of medical toxicology at Rutgers New Jersey Medical School, told Healio. “People take these things because they are being marketed for this purported health claim some would say borders on quackery and unethical marketing behaviors.”

Dangers

The main issue with colloidal silver is its ingestion, Nelson, who is also a member of the Healio Primary Care Peer Perspective Board, said.

“Unlike many things that we eat — our kidney filters them or our liver filters them — silver is very poorly eliminated,” he said. “Your body has no way to get rid of it.”

When ingested, much of the silver is absorbed into the body and builds up over time. With nowhere else to go, it deposits in a patient’s skin, Nelson explained. This is notably different from the FDA-approved silver sulfadiazine because, as a topical antibacterial, only a small amount of silver is absorbed through the wound, he said.

“People have unrealistic expectations of the benefits of dietary supplements and, to some extent, the risks,” he said. “You're taking a drop of liquid a day — how bad could it be?”

Chideya and Nelson said that colloidal silver intake can cause serious adverse events. For example, Chideya said it can cause low absorption of some drugs like thyroxine and certain antibiotics, and there is some research indicating that it can cause nervous system, liver and kidney problems.

“It's hard to know if somebody [who] has argyria has cancer because they smoked or because they took silver, just as an example,” Nelson explained. “It's very hard to make these connections, ... but animal models support that it is toxic to various organs.”

Both experts agreed the most serious and common side effect is argyria, a typically permanent discoloration of the skin from a buildup of silver in tissues.

“Suddenly your skin starts turning color,” Nelson said. “Before you know it, you can turn a pretty deep shade of gray or blue gray.”

Argyria

The complications of argyria are rare — according to the FDA adverse events reporting system public dashboard, there have been seven cases in the last 10 years — and almost entirely cosmetic, but this does not mean they are insignificant.

“In the big picture, argyria is a small problem. But to those people, it's a terrible disease,” Nelson said.

“This is permanent ... their skin is never going to look normal again, and it is completely preventable,” he added. “It’s a matter of getting people to stop taking more. There’s really nothing to do for it.”

Enlarge 

Chideya said that although argyria has no specific treatment, prevention includes avoiding all colloidal silver products and ensuring open communication between patients and primary care providers. She stressed that it is crucial for PCPs to be informed about dietary supplement trends, educate patients on health practices that are evidence based and encourage open communication about all health practices.

“As with all treatments, health care providers should ask their patients why they want to use colloidal silver and think it may be more beneficial than other options,” she said. “This discussion may help health care providers understand the underlying motivations and guide them to safer, more evidence-based therapies for the condition(s) under consideration.”

An important message for PCPs is that it is “always worth asking” patients about their dietary supplements — to, “at the very least, just open up the conversation,” Nelson said.

“Many patients don't bother to tell you about them, because they think that they're natural and therefore safe, and they often feel like their doctors are going to be judgmental about their dietary supplement use,” he continued. “There are some that certain people at certain ages or stages of life shouldn't take, and then there are some that are patently unsafe, like this one.”

References:

• Dietary supplements. Available at: https://www.fda.gov/food/dietary-supplements. Accessed Aug. 12, 2024.
• FDA adverse events reporting system public dashboard. Available at: https://fis.fda.gov/sense/app/95239e26-e0be-42d9-a960-9a5f7f1c25ee/sheet/45beeb74-30ab-46be-8267-5756582633b4/state/analysis. Accessed Aug. 13, 2024.
• NCCIH. Colloidal silver: What you need to know. Available at: https://www.nccih.nih.gov/health/colloidal-silver-what-you-need-to-know. Accessed Aug. 12, 2024.