colloidal silver
Colloidal silver has no proven health benefits, and many known undesirable side effects.
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  • Colloidal silver is not safe and too much of it can cause serious side effects like muscle weakness, kidney problems, and neurological damage.
  • Taking colloidal silver can also lead to an incurable condition called argyria which turns the skin and gums blue.
  • Companies that market colloidal silver as a health remedy are not supported by the FDA and some companies have even been issued FDA warnings for their fraudulent claims.
  • This article was medically reviewed by Alex Berezow, PhD, a microbiologist at the American Council on Science and Health. 
  • This story is part of Insider’s guide on How to Kill Germs.

Silver is known for its antibacterial properties, which kill a range of microbes, bacteria, and fungus. Silver damages bacterial cell walls, enters and disrupts bacterial cells, and stops the replication of bacteria by damaging its DNA. 

“The use of silver as vessels to store food and drink to avoid spoilage was common in ancient civilizations,” says Wong Siew Wei, MD, at The Cancer Centre and Singapore Medical Group. 

One of the most common forms of silver is colloidal silver, a water solution containing small particles — ions and nanoparticles — of silver. It was first used in 1891 to sterilize wounds.

Today, some peddle the metallic ingredient in dietary supplements and beauty products, claiming it can be a miracle cure — despite the fact that there’s a serious lack of evidence to support any health benefits of consuming colloidal silver or applying it to your skin. 

Colloidal silver is not safe to consume 

While the antimicrobial properties of silver are well-studied, the suggested benefits of colloidal silver as a dietary supplement have not been scientifically proven.

"There are currently no FDA-approved prescription or over-the-counter drugs containing colloidal silver that are taken by mouth," says Wong. "In 1999, the FDA warned that oral colloidal silver is neither safe nor effective for treating any disease or condition." 

In fact, the FDA recently issued warnings against seven companies that claimed to sell products that cured or prevented the coronavirus, including colloidal silver. 

Wong says that companies selling products with colloidal silver that claim to prevent or cure illnesses like coronavirus are a major threat to public health, as they might stop or delay consumers from seeking the appropriate medical treatment.

Overall, the FDA and Mayo Clinic, to name just two, point out the lack of scientific evidence for the oral use of colloidal silver. It's important to note that silver has no nutritional function in the body, and is not an essential part of the human diet. 

Colloidal silver can have dangerous side effects 

Proponents of consuming colloidal silver claim that it can help boost the immune system, purify water, and cleanse the gut. Beauty brands suggest the ingredient, when applied topically, is anti-inflammatory and reduces irritation on the skin. 

And while the evidence is lacking for any of these supposed benefits of colloidal silver, there's been plenty of studies proving the harmful effects of the substance. 

"The silver in colloidal silver products gets deposited into organs such as the skin, liver, spleen, kidney, muscle, and brain," says Wong. "This can lead to argyria, a condition characterized by irreversible bluish looking skin that first appears in the gums." 

Wong says that this blue tinge may have led to the rise of the term 'blue blood' as a descriptor for the aristocracy, as the use of silver was widespread among wealthier families in ancient times. One of the most notable recent instances of argyria is Paul Karason, the 'blue man' who appeared on The Oprah Winfrey Show in 2008 after drinking extreme amounts of colloidal silver.

A 2009 case report on argyria noted the increasing use of colloidal silver in alternative and homeopathic remedies and warned against its use. It's important to always know what you're taking, whether it's a natural supplement or not, and make sure to run everything past a licensed doctor or medical practitioner first. 

As if turning blue wasn't a risky enough side effect, colloidal silver can cause problems for those taking certain medications. "Colloidal silver interferes with drug absorption," says Wong, which is how effectively medication enters the bloodstream. "For example, the absorption of antibiotics from the quinolones and tetracyclines families are decreased with concomitant colloidal silver use." 

Quinolone antibiotics include ciprofloxacin, a common treatment for urinary tract infections (UTIs) and respiratory infections, while tetracycline antibiotics are commonly used to treat malaria. Colloidal silver has also been shown to reduce the absorption of thyroxine, a medication used to treat thyroid deficiency. 

According to Mayo Clinic, excessive consumption of silver has been linked to kidney damage and neurological issues, such as having seizures. Another 2017 case study also noted instances of muscle weakness and that some cases of argyria result in myopathy, a disease of muscle tissues.

The bottom line: Don't apply or consume colloidal silver 

Wong, along with NCCIH, says that using silver topically on the skin is fine in medical situations, such as for bandages and dressings when treating infections, burns, or wounds on the skin. 

Outside the body, the amount of silver you might come into contact with through jewelry or household objects is perfectly safe. But applying colloidal silver to your skin has no proven health benefits, and many known harmful side effects. 

And don't consume colloidal silver. There's absolutely no evidence that ingesting it prevents disease or helps the immune system in any way. If you're looking to prevent disease, it's better to stick with tried-and-tested methods: wash your hands, and avoid social contact. 

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