- Rajani Katta MD
Activated Charcoal and the Science of Skin Care: Some Promise, Lots of Hype
Updated: Aug 16, 2020
Activated charcoal has been all the rage lately, and it's no wonder. (Black ice cream! Black face masks!) But when you look at the science behind the use of activated charcoal in skin care, it's definitely being overhyped. While it may help in some types of skin care products and for some types of skin conditions, for others the science just doesn't back it up.
Here are four skin care products that make use of activated charcoal, along with a breakdown of the science behind them.
Activated charcoal is all the hype lately for skin care products, but the science doesn't back it up for many claims
1. Cleansers and masks If you look at the ads, many claim that activated charcoal works like a magnet, "pulling up oil and toxins from your skin and from deep inside your pores."
I doubt it. If you look at the science behind how activated charcoal actually works, it doesn't seem likely that a cleanser containing it can do all that.
Many products containing activated charcoal claim that they will pull (like a magnet!) oil and toxins from your skin and pores. But the science doesn't suggest that's likely
Activated charcoal works by a process called adsorption. This is defined as the "phenomenon in which a solid substance attaches other substances to its surface without covalent binding."
In other words, liquid or gas molecules become attached to the solid surface of the activated charcoal. How do they become attached? Not through magnetism, but rather by weak intermolecular forces. And these forces can be impacted by a lot of different factors.
Activated charcoal works through adsorption, a process whereby a solid substance attaches other substances to its surface via weak intermolecular forces.
I think of it like swimmers clinging to the side of a ship.
I think of it this way. Think about taking a big cruise ship, parking it right offshore, and hoping that you can get swimmers to cling onto the side of your boat. That's adsorption: a solid substance attaching other substances to its surface. If you want a lot of swimmers to latch on, it helps if you're close by, and it helps if you're parked there for a long time.
That's the way adsorption works: it's more effective with shorter distances and with longer contact time.
Because of these weak forces, and the impact of these other factors, you really can't claim that adsorption "works like a magnet".
But wait! There are even more factors that impact this process, which means that the way your cleanser is formulated may impact how well the adsorption works. In fact, I'd love to see the studies done by the manufacturers, because there are hardly any published research studies on the use of activated charcoal in skin care products.
If you look at other research, though, you'll find that lots of other factors can impact the effectiveness of activated charcoal.
Activated charcoal has actually been used, and studied, in water purification for a long time. What we know is that if you want to remove oil from water using activated charcoal, it takes a lot of fine-tuning to make this process work effectively. You need the right binder for the charcoal, and you need the right dose of charcoal. You also need the right temperature and the right pH for the process to work well.
That's one of the reasons I'd love to see the studies: in formulating an effective product, you need to take all of these factors into account.
In terms of cleansers, they may work just fine for skin cleansing--not because of the charcoal, but because most use charcoal along with other ingredients. And those other ingredients may be the ones that are actually doing the heavy work of cleansing.
If that's the case, and the charcoal isn't actually doing much, is there any downside to using it? Well, it's an inert substance, so we wouldn't expect allergic reactions. However, it is slightly abrasive, so if you have sensitive skin, you'd want to be careful.
In terms of masks, they are in contact longer with the skin, but is 5-10 minutes really long enough for it to work? And has the manufacturer really optimized the binder, the dose, and these other considerations? Without seeing the studies, there's no way to know, but I'd be hesitant to say they're likely to work any better than other ingredients.
2. Exfoliants If you're looking for a mild physical exfoliant, on the other hand, activated charcoal may be helpful.
Activated charcoal can be used as an exfoliant. However, chemical exfoliants have been better studied, and are known to be effective
But would I choose it over other exfoliating ingredients? Probably not. If you're looking for exfoliation, you can use physical exfoliation (like a gentle scrub) or chemical exfoliants (such as glycolic acid and salicylic acid). We know, from many years of experience, that glycolic acid and salicylic acid are very effective exfoliating ingredients. We also know how different concentrations of these ingredients are likely to affect your skin. Because of that long experience with these chemicals, I'd be more likely to reach for glycolic acid or salicylic acid if I was looking for an effective exfoliant.
3. Specially formulated wound dressings for chronic odor-causing open wounds There have been published studies on the use of activated charcoal in conjunction with other ingredients in wound care dressings. These are dressings that are used for many hours, or even days, to treat chronic open wounds.
Activated charcoal used in specially formulated wound dressings has been found to help reduce odor and in some cases improve healing of chronic open wounds.
Some studies have indicated that these may help reduce the odor associated with some chronic open wounds. That makes sense, because the gas molecules that cause odor are likely to adsorb onto the surface area of activated charcoal. Some studies, although small, have even found improved wound healing of these chronic open wounds.
However, these studies were done with wound dressings that were carefully formulated by the manufacturer. I definitely wouldn't reach for just any wound dressing, because activated charcoal by itself could be abrasive to the skin.
However, for physicians treating chronic open wounds, the use of these specially formulated wound dressings may be a potential choice.
4. Deodorant If activated charcoal has the potential to absorb odor molecules, could you use it in a deodorant?
Some deodorants containing activated charcoal seem promising, due to the charcoal's odor-absorbing properties--- but be cautious of potential abrasiveness.
There have been some products promising just that. While the science behind this use appears promising, you would still have to be very cautious, due to charcoal's potential to abrade the skin.
You also have to be careful about the other ingredients in these deodorants. Some of these use essential oils, and I'm seeing a LOT of allergic reactions to the essential oils in deodorants. Overall, though, this is one area where I'd like to test out the products.
So how does activated charcoal come out in the final analysis?
1. Cleansers and masks. Research is lacking on its use in cleansers, but based on the science of adsorption, it doesn't appear promising. However, if you can handle its abrasiveness and you like it, it should be fine to use if it's formulated with other effective cleansing ingredients. 2. Exfoliants. Activated charcoal may serve as a mild physical exfoliant, but I prefer chemical exfoliants such as salicylic acid or glycolic acid. We have a lot of experience with these chemical exfoliant ingredients, and they're known to be safe and effective at the right doses. 3. Wound dressings. For chronic open wounds, a carefully formulated and manufactured AND tested product may help reduce odor. These special wound dressings would be prescribed by a physician. 4. Deodorants. Intriguing, since activated charcoal does absorb odors well. I'd be interested to see studies looking at these products. However, I'd need to test these out first, due to charcoal's potential to abrade the skin. And I would be really careful about products with essential oils, especially for people with sensitive skin (due to the risk of allergic skin reactions).
Dr. Rajani Katta is the author of Glow: The Dermatologist's Guide to a Whole Foods Younger Skin Diet. To receive future updates on preventive dermatology and the role of diet, sign up here.
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