Activated charcoal can be found almost everywhere: in toothpaste, skin care products, baked goods, beverages and water filtration systems. Here's what you need to know about this seemingly ubiquitous ingredient.
What makes it activated?
Activated charcoal is created from carbon-rich materials burned at high temperatures, according to the National Capital Poison Center (Poison Control). For example, carbon-rich materials such as wood, coconut shells or coal, are burned at a high temperature (between 600 and 900 degrees Celsius or 1,110 and 1,650 degrees Fahrenheit) to create a charcoal powder.
The charcoal powder is then typically charred with some additional material, such as chloride salts, to help create the porous structure, according David O. Cooney's book "Activated Charcoal: Antidote, Remedy and Health Aid" (TEACH Services, Inc., 2016). The excess material is then washed away with a dilute acid solution to leave the pure carbon. The charcoal can further be treated to create a finer network of pores, and therefore additional surface area, by exposing it to an oxidizing gas, such as steam or carbon dioxide.
So much additional surface area is created during the activation process that 50 grams of activated charcoal (which is about the weight of 20 U.S. pennies) has 17.5 times more surface area than a full-size football field, according to a 2016 study in the British Journal of Clinical Pharmacology.
What is activated charcoal good for?
Health professionals administer activated charcoal to patients who have overdosed with certain drugs or have been poisoned, according to Poison Control. The fine powder is often mixed with water or other liquid and drunk by the patient or given via a feeding tube to clean out the gastrointestinal tract as an alternative to stomach pumping.
The activated charcoal acts like a sponge: Toxin particles bind to the surface of the activated charcoal so that the toxin is less likely to be absorbed into the body. This works best with toxins that contain organic particles (which are compounds that contain carbon and are usually bonded with oxygen, hydrogen or nitrogen). Depending on the type of overdose or toxin, a single dose of activated charcoal can be a very effective treatment if given quickly enough.
Poison Control recommends that people don't try to use activated charcoal at home to treat a potential overdose or toxin ingestion. Most activated charcoal available over the counter is not as "activated" as what would be given in the emergency room, and it may not be the best solution for your ailment.
There is very little scientific evidence showing that activated charcoal is effective for things like high cholesterol, diarrhea or constipation, gas or indigestion, or that it prevents hangovers (activated charcoal does not bind with alcohol) or promotes wound healing, according to the U.S. National Library of Medicine.
There's no research to suggest that activated charcoal should be consumed as part of a so-called "detox" diet, or that it's healthy to consume activated charcoal at all if you're not poisoned. In fact, it's probably unhealthy to consume it if you don't need it. A 2007 study published in the Journal of Food Quality found that activated charcoal eliminated the healthy vitamins found in apple juice.
Activated charcoal is also commonly found in water filtration systems, respiratory masks and air filters. Just as it removes toxins from our body, the activated charcoal attracts and binds to contaminants in water and air including radon, fuels, solvents and many industrial and radioactive chemicals, and protects us against breathing or ingesting them, according to the United States Environmental Protection Agency (EPA).
What is activated charcoal not good for?
Activated charcoal can now readily be found in many over-the-counter health and beauty products, including toothpaste. Most charcoal-containing toothpastes are incredibly abrasive to tooth enamel and can lead to highly sensitive teeth, which are yellowed due to stripped enamel and more prone to dental decay, according to Benjamin Schwartz, a doctor of dental surgery and a clinical assistant professor at Touro College of Dental Medicine at New York Medical College.
"There are very few clinical studies that outline long-term benefits of charcoal toothpastes. Instead, many of those studies show long-term risks with prolonged use of charcoal toothpaste," Shwartz said.
In addition, most activated charcoal toothpastes do not contain fluoride and may even reverse the benefits of fluoride, which is a key ingredient for preventing dental cavities.
Activated charcoal can be found in everything from shampoos and conditioners to facial washes and masks, with claims that it can soak up excess oils and other impurities. While activated charcoal may be relatively safe when used topically, there is no clinical evidence to support the claim that activated charcoal does anything to eliminate cosmetic imperfections, according to a 2019 study in the journal Clinics in Dermatology.
Many companies advertise the presence of activated charcoal in their product and claim that their offering is therefore antiviral, antibacterial or antifungal. But there is scant scientific evidence that these products provide any health benefits, Schwartz said.
"The charcoal does absorb other minerals, so theoretically it can absorb and inactivate bacterial or viral cells, but to what extent is anyone's guess," he said. "And what is stopping the charcoal from then inactivating the healthy bacteria that reside in the oral cavity?"
If the claims promoting activated charcoal in toothpaste as well as other health and beauty products could somehow magically become substantiated by science, it would be a really big deal, Schwartz said. "If we could use a toothpaste that would selectively attack the microscopic offender, then the fight against dental disease would be much easier to win!"
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Rachel Ross is a science writer and editor focusing on astronomy, Earth science, physical science and math. She holds a Bachelor of Arts in Philosophy from the University of California Davis and a Master's degree in astronomy from James Cook University. She also has a certificate in science writing from Stanford University. Prior to becoming a science writer, Rachel worked at the Las Cumbres Observatory in California, where she specialized in education and outreach, supplemented with science research and telescope operations. While studying for her undergraduate degree, Rachel also taught an introduction to astronomy lab and worked with a research astronomer.