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Natural supplements and holistic remedies that offer proven health benefits are big in my house. One that I always keep on hand is colloidal silver. This sometimes controversial supplement was used before antibiotics existed for bacterial infections and to support the immune system.
Colloidal silver products are still often used today and many holistic health experts say that it’s a highly beneficial cure-all. On the flip side, the Food and Drug Administration (FDA) has not approved the use of colloidal silver for any health purpose, and other health care experts like doctors from Mayo Clinic also do not believe that it is safe.
Despite this, with the rise of antibiotic resistance, silver is making a comeback as a powerful broad-spectrum antimicrobial. Many swear by colloidal silver for everything from pink eye to ear infections.
So is colloidal silver really a safe and useful natural remedy?
What Is Colloidal Silver?
Colloidal silver is made when silver nanoparticles are synthesized and suspended in a solution of simple sugars and ammonia. These particles are so small that they aren’t visible to the eye and can be as tiny as one ten-thousandth the width of a human hair. That’s extremely tiny!
Modern medicine still relies on silver for antibacterial benefits:
- Many medical companies coat their devices with silver to avoid bacterial biofilms.
- Hospitals treat newborns with silver nitrate drops to prevent gonorrhea eye infections.
- Silver solutions or gauze are used to help treat burn wounds.
Colloidal silver is generally considered safe to use, but it is important to be informed about what studies say with respect to its safety and effectiveness, and whether excessive use may harm us or the environment.
The size of the colloidal silver particles is the most important thing that determines if they have health benefits or not, with smaller particles and lower concentrations being most effective against harmful antibiotic-resistant bacteria.
How Does Colloidal Silver Work?
Scientists have observed that silver kills germs, but they still don’t completely understand how. A lack of strong scientific evidence means the use of colloidal silver is still somewhat controversial.
The general idea is that silver nanoparticles bind to bacteria cell walls. A fraction of these nanoparticles may react to substances in the body or the environment and become silver salt, which is antimicrobial.
Although most colloidal silver is made from silver salts, they are different things. Silver salts are a lot more toxic to both humans and bacteria than colloidal silver. Silver salts have a positive charge that binds up proteins, cause DNA damage, and disrupt the respiratory processes in bacteria. Silver nanoparticles may be neutral or negatively charged, depending on how it is synthesized.
Silver ions are more likely to cause silver toxicity or argyria in humans than the colloidal version. However, because a fraction of colloidal silver may become silver salt, overconsumption of colloidal silver can still cause silver toxicity when taken at very high doses.
Since it is potent, it’s important to be careful when using this supplement.
Benefits of Colloidal Silver
Silver is a metal and a non-essential element in the body. It is much safer to a human body than other heavy metals like lead and mercury. We can accumulate much more silver in our bodies before it becomes toxic.
Research suggests that colloidal silver works for:
- Killing and preventing bacterial growth, including bacteria that is antibiotic-resistant.
- Treating burn infections as a topical antimicrobial
- Killing some strains of pathogenic yeasts, including Candida and Cryptococcus
- Preventing certain viruses, like HIV/AIDS and RSV, from entering human cells
- Reducing inflammation from contact dermatitis and irritating rashes in animal studies
- Disrupting bacterial biofilm (a slimy shield that allows bacteria to hide from antibiotics) in sinus infections in sheep
- Being toxic to certain cancer cells
- Effectively fighting bacteria that can cause deadly diarrhea (Vibrio cholera and a dangerous strain of E. coli).
- Fighting fungal infections on the skin.
A Note About Bacteria, Viruses, and Yeasts
To date, all studies that test the effects of colloidal silver with bacteria found that it is effective. There are mixed reviews when it comes to yeasts and viruses.
A comprehensive study by naturopathic doctors in the Journal of Alternative and Complementary Medicine found that it is only effective against some strains of yeasts but not others. That same study found that colloidal silver is not effective against viruses.
Another in vitro study in the Journal of Wound Care tested 3 different market brands and found no effectiveness whatsoever.
Colloidal silver is a powerful antimicrobial. However, its effectiveness as an antiviral or antifungal can vary depending on the particular infection and quality of the product itself.
Is Colloidal Silver Safe?
Natural remedies are appealing, but safety is an important issue.
There have not been large studies done in humans to truly examine whether colloidal silver is safe or effective. Most tests are done in vitro, meaning that they’re done in test tubes or Petri dishes. This allows researchers to understand how it behaves in isolated situations. But the human body isn’t isolated, and having a whole-body understanding is different from in vitro studies.
A human body is a lot more complex than a Petri dish! Just because something kills germs in a Petri dish doesn’t mean we should take it to prevent or treat an infection. We still need to understand how silver affects the rest of the body, and whether it can travel to where we need it most if taken internally. More studies are needed to understand how it works in our bodies (in vivo).
With the evidence that we do have, though, we can make some conclusions:
As with many supplements, colloidal silver can affect other parts of the body that go beyond the reason it’s being taken. Two animal studies independently looked at how the gut bacteria balance of mice and rats was affected by being fed colloidal silver. The results found a disruption in gut flora.
Another study that examined digestive tissue after the ingestion of colloidal silver found that it can damage gut cells. Yet a newer study in Nanotoxicology that looked at mice found no changes to gut bacteria or cell structure.
So, there are mixed reviews.
It’s also not known how effective colloidal silver is outside of the gut, elsewhere in the body. When colloidal silver is taken internally, the small intestine can absorb around 10 to 18% of silver nanoparticles into the bloodstream. The remaining silver nanoparticles pass through the gut.
In the blood, nanoparticles bind to a protein called albumin as it gets carried around the body. Silver proteins are a lot less effective against germs than silver alone, so we really don’t know how it behaves throughout the body.
Skin Discoloration (argyria)
It is possible to get too much silver build-up in the body. This condition is called argyria or argylosis, where silver accumulates in tissues and turns the person blue or gray… permanently! When this happens, the silver does not usually cause health problems in other ways, although it can be traumatic to have discolored skin.
Colloidal silver might seem like a promising option over antibiotics, but it still has some of the side effects of antibiotics. For this reason, I’ve always exercised caution and not over-used it, as evidence shows it may be harmful if used regularly or over a long period of time.
Gut bacteria can also become resistant to colloidal silver, just like with antibiotics. This is especially true when it has been used for several generations.
Silver nanoparticles cause some environmental concerns. Currently, silver nanoparticles are present in the environment at concentrations that are about one thousand times the dose that would be toxic to fish and other marine animals.
Silver nanoparticles are also found in sewage sludge that is used in landfills. This presents a risk of it getting reabsorbed back into the food supply. While it is somewhat known how colloidal silver affects human gut bacteria, it is still not completely clear how it affects the health of bacteria, yeasts, and other microorganisms in the environment.
Since the health of our soil is closely linked to the health of the gut, we need to be careful about messing it up.
Group B Strep (GBS) is a bacteria that is commonly found in humans, but during pregnancy it can represent the risk of infection for the baby during the birthing process. Antibiotics are given to prevent complications. Mothers wanting to avoid antibiotics might wonder if colloidal silver is a safe alternative.
Colloidal silver has not been studied specifically for GBS or generally for pregnancy. Because it can be toxic—and because supplements in pregnancy can have unknown effects on the developing baby—it’s important not to use supplements to self-medicate during pregnancy, either internally or topically.
Cautions for Colloidal Silver
Colloidal silver is a natural remedy that has been used for thousands of years. Does that mean it should still be used today? There is reason to be careful about using it.
- Colloidal silver is marketed as a dietary supplement and is relatively unregulated. Only the manufacturer is responsible for the safety and effectiveness of their products. A random test of colloidal silver products for sale found several that were ineffective or even contaminated with bacteria. Yuck!
- While colloidal silver might be safe and effective when used externally, or when targeting pathogens in the gut, it can also have unintended consequences. Because colloidal silver does have some side effects, research suggests using it carefully rather than liberally.
- Colloidal silver can mess with or enhance the effects or side effects of some medications. Always check with your doctor before starting it or using it alongside anything else.
As discussed above, the safest use based on studies is external application to wounds and as a sinus rinse.
Colloidal Silver Products
If you choose to buy colloidal silver, it’s important to make sure you’re getting a pure product. Colloidal silver ingredients should only include silver and water. There should not be anything else in it.
When choosing your product, you also want to keep the particle size in mind. This refers to how big (or small) the nanoparticles of silver are. The concentration of particles per unit of water is listed in parts per million, or PPM. Basically, how many silver particles are collected per serving of water.
When you’re looking at buying colloidal silver, higher PPM is not better. Supplements are considered to be safest when they are between 10 and 20 PPM. Taking in too much colloidal silver can result in becoming toxic or having other complications, like the graying of skin.
If you choose to use colloidal silver, be sure to buy from a reputable brand. There are many available, but this is the brand I keep on hand for external use and as a sinus rinse.
How to Use Colloidal Silver
While we’ve covered some concerns, there are lots of ways to use colloidal silver safely as a part of your natural medicine cabinet.
Check out the ways that you can use colloidal silver:
- Nasal rinse: Add a few drops to distilled water (don’t combine with salt!) and use your neti pot as usual to rinse the sinus cavity.
- Ear infections: Use 2-3 drops in the ear, a few times a day, until symptoms subside.
- Pink eye: Add 2-3 drops directly to the infected eye, 3-4 times daily or until symptoms go away.
- Skin fungus or ringworm: Treat patchy skin infections with a few drops applied directly 2-3 times per day. Let dry on the skin to get the full effect.
- Toenail infections: Add 2-3 drops to the top of the infected toenail. Use 3-4 times a day until symptoms clear up.
- First aid disinfectant: Use as you would other antibacterial creams for minor cuts, scrapes, or bug bites.
- Acne: Add 1-2 drops to acne breakouts 3-4 times a day.
- Gingivitis: Add 1 teaspoon to purified water and swish in the mouth, 2-3 times per day.
This article was medically reviewed by Dr. Scott Soerries, MD, Family Physician and Medical Director of SteadyMD. As always, this is not personal medical advice and we recommend that you talk with your doctor.
What’s your experience with colloidal silver? Please share in the comments below.
- National Center for Complementary and Integrative Health. (2017). Colloidal silver. https://www.nccih.nih.gov/health/colloidal-silver
- Bauer, B.A. (2017). Colloidal silver: Is it safe? https://www.mayoclinic.org/healthy-lifestyle/consumer-health/expert-answers/colloidal-silver/faq-20058061
- Alexander, J.W. (2009). History of the medical use of silver. https://www.liebertpub.com/doi/abs/10.1089/sur.2008.9941
- Mijnendonckx, K., Leys, N., Mahillon, J., Silver, S., & Van Houdt, R. (2013). Antimicrobial silver: uses, toxicity and potential for resistance. https://link.springer.com/article/10.1007/s10534-013-9645-z
- Zhang, X. F., Liu, Z. G., Shen, W., & Gurunathan, S. (2016). Silver Nanoparticles: Synthesis, Characterization, Properties, Applications, and Therapeutic Approaches. https://www.mdpi.com/1422-0067/17/9/1534
- Panacek, A., Kvitek, L., Prucek, R., Kolar, M., Vecerova, R., Pizurova, N., Sharma, V.K., Nevecna, T., and Zboril, R. (2006). Silver colloid nanoparticles: Synthesis, characterization, and their antibacterial activity. https://pubs.acs.org/doi/10.1021/jp063826h
- Wiemken, T. L., Kelley, R. R., Carrico, R. M., Binford, L. E., Guinn, B. E., Mattingly, W. A., Peyrani, P., & Ramirez, J. A. (2015). Efficacy of a novel skin antiseptic against carbapenem-resistant Enterobacteriaceae. https://www.ajicjournal.org/article/S0196-6553(14)01377-7/fulltext
- Huang, L., Dai, T., Xuan, Y., Tegos, G. P., & Hamblin, M. R. (2011). Synergistic combination of chitosan acetate with nanoparticle silver as a topical antimicrobial: efficacy against bacterial burn infections. https://journals.asm.org/doi/full/10.1128/AAC.01803-10
- Morrill, K., May, K., Leek, D., Langland, N., Jeane, L. D., Ventura, J., Skubisz, C., Scherer, S., Lopez, E., Crocker, E., Peters, R., Oertle, J., Nguyen, K., Just, S., Orian, M., Humphrey, M., Payne, D., Jacobs, B., Waters, R., & Langland, J. (2013). Spectrum of antimicrobial activity associated with ionic colloidal silver. https://www.liebertpub.com/doi/10.1089/acm.2011.0681
- Rai, M., Deshmukh, S.D., Ingle, A.P., Gupta, I.R., Galdiero, M., and Galdiero, S. (2013). Metal nanoparticles: The protective nanoshield against virus infection. https://www.tandfonline.com/doi/abs/10.3109/1040841X.2013.879849
- Bhol, K. C., & Schechter, P. J. (2005). Topical nanocrystalline silver cream suppresses inflammatory cytokines and induces apoptosis of inflammatory cells in a murine model of allergic contact dermatitis. https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-2133.2005.06575.x
- Nadworny, P. L., Wang, J., Tredget, E. E., & Burrell, R. E. (2008). Anti-inflammatory activity of nanocrystalline silver in a porcine contact dermatitis model. https://www.sciencedirect.com/science/article/abs/pii/S1549963408000452
- Rajiv, S., Drilling, A., Bassiouni, A., James, C., Vreugde, S., & Wormald, P. J. (2015). Topical colloidal silver as an anti-biofilm agent in a Staphylococcus aureus chronic rhinosinusitis sheep model. https://onlinelibrary.wiley.com/doi/abs/10.1002/alr.21459
- Juarez-Moreno, K., Gonzalez, E. B., Girón-Vazquez, N., Chávez-Santoscoy, R. A., Mota-Morales, J. D., Perez-Mozqueda, L. L., Garcia-Garcia, M. R., Pestryakov, A., & Bogdanchikova, N. (2017). Comparison of cytotoxicity and genotoxicity effects of silver nanoparticles on human cervix and breast cancer cell lines. https://journals.sagepub.com/doi/10.1177/0960327116675206
- Salem, W., Leitner, D. R., Zingl, F. G., Schratter, G., Prassl, R., Goessler, W., Reidl, J., & Schild, S. (2015). Antibacterial activity of silver and zinc nanoparticles against Vibrio cholerae and enterotoxic Escherichia coli. https://www.sciencedirect.com/science/article/pii/S1438422114001532
- Ayatollahi Mousavi, S. A., Salari, S., & Hadizadeh, S. (2015). Evaluation of Antifungal Effect of Silver Nanoparticles Against Microsporum canis, Trichophyton mentagrophytes and Microsporum gypseum. http://www.ijbiotech.com/article_11913.html
- van Hasselt, P., Gashe, B. A., & Ahmad, J. (2004). Colloidal silver as an antimicrobial agent: fact or fiction?. https://www.magonlinelibrary.com/doi/abs/10.12968/jowc.2004.13.4.26606
- Williams, K., Milner, J., Boudreau, M. D., Gokulan, K., Cerniglia, C. E., & Khare, S. (2015). Effects of subchronic exposure of silver nanoparticles on intestinal microbiota and gut-associated immune responses in the ileum of Sprague-Dawley rats. https://www.tandfonline.com/doi/abs/10.3109/17435390.2014.921346
- van den Brule, S., Ambroise, J., Lecloux, H., Levard, C., Soulas, R., De Temmerman, P. J., Palmai-Pallag, M., Marbaix, E., & Lison, D. (2016). Dietary silver nanoparticles can disturb the gut microbiota in mice. https://particleandfibretoxicology.biomedcentral.com/articles/10.1186/s12989-016-0149-1
- Fröhlich, E. E., & Fröhlich, E. (2016). Cytotoxicity of Nanoparticles Contained in Food on Intestinal Cells and the Gut Microbiota. https://www.mdpi.com/1422-0067/17/4/509
- Wilding, L. A., Bassis, C. M., Walacavage, K., Hashway, S., Leroueil, P. R., Morishita, M., Maynard, A. D., Philbert, M. A., & Bergin, I. L. (2016). Repeated dose (28-day) administration of silver nanoparticles of varied size and coating does not significantly alter the indigenous murine gut microbiome. https://www.tandfonline.com/doi/abs/10.3109/17435390.2015.1078854
- Graves, J. L., Jr, Tajkarimi, M., Cunningham, Q., Campbell, A., Nonga, H., Harrison, S. H., & Barrick, J. E. (2015). Rapid evolution of silver nanoparticle resistance in Escherichia coli. https://www.frontiersin.org/articles/10.3389/fgene.2015.00042/full
- Holler, J.S., Nordberg, G.F., and Fowler, B.A. (2007). Silver. https://www.sciencedirect.com/science/article/pii/B978012369413350094X
- McGillicuddy, E., Murray, I., Kavanagh, S., Morrison, L., Fogarty, A., Cormican, M., Dockery, P., Prendergast, M., Rowan, N., & Morris, D. (2017). Silver nanoparticles in the environment: Sources, detection and ecotoxicology. https://www.sciencedirect.com/science/article/abs/pii/S0048969716322070