Article by: Perry Romanowski

On a Facebook page that I participate in someone there was a discussion about extracts in cosmetics and someone posed the question herbal-extracts

“Do a significant number of cosmetic chemists and formulators really hold that extracts are worthless in a product?”

This quick answer is Yes. Most cosmetic chemists that I know believe that extracts in a formulation are nothing more than claims ingredients added to support the story that the marketing group wants to tell about the product. We do not expect these ingredients to have any impact on the functionality of the product.

This position naturally leads to some questions which I’ll address now.

Why don’t you think they do anything?

There is so much (mis)-information about natural extracts on the Internet that it is understandable people would think they have some benefit. Additionally, there is the wisdom of ancestors that helps reinforce the idea that certain home remedies provide great benefits. On my other website The Beauty Brains we frequently get asked whether this or that treatment suggested by someone’s grandmother is really going to improve hair or skin. And many people use treatments like olive oil, apple cider vinegar, lemon juice or things like this as beauty treatments. There just seems to be a natural inclination to want to believe that nature provides everything we need to have great looking skin and hair.

As a scientist our goal is to create the best performing product that we can make. This mean taking all the materials that we can access, testing them to see their effect, improving on things that work and rejecting things that do not work. Most importantly, we are (should be) driven by testing and data. If aloe vera does not moisturize better than petrolatum there is no performance reason we should use aloe vera. If it did, than we should use it.

So, why don’t chemists think extracts do anything? Because there is no evidence to demonstrate that they do. If there was evidence that extracts did something in the formula, even at high levels, then these things would be used at a high level in formulas. The fact that there is no evidence of functionality is the reason they aren’t used.

Evaluating Evidence of Extract Effectiveness

Now if you want to prove that an extract has an effect you have to do some testing. This is where things get tricky. In the cosmetic area we have a limited amount of reliable testing however, we do have some. We can measure for moisturization, anti inflammatory response, and some other things.

But any claim that can be made about an ingredient should be disbelieved until there is some evidence that it is true.

I think this is where non-scientists and scientists diverge. Non-scientists begin with a conclusion (XX extract has some positive effect) whereas scientists begin with not knowing (XX extract might have some positive effect). If you start an investigation with a belief that something works you are going to collect data that supports your belief and reject data that doesn’t support it. This isn’t scientific and it results in you reaching potentially erroneous conclusions. If you start an investigation with an open mind you are going to make conclusions based on all the data collected, not just the things that support what you want to believe.

So how do you prove an extract “works”?

Here is a three step method for demonstrating an extract works.

Step 1Screen the ingredient at a high level through some standard test. If you want to prove something is moisturizing, conduct a TEWL study. If you want to show that something is an antioxidant, conduct an antioxidant assay. If something is supposed to be good for hair, dunk a hair tress in the extract and measure it for things like shine, detangling, strength or anything else. At this point you don’t even have to test it against anything beyond a blank control. If you can’t see some obvious benefit at this point, it’s not worth pursuing further. If the neat ingredient doesn’t do anything, putting it in a formulation won’t help.  The vast majority of extracts fail at this point.  But if it doesn’t, certainly move on to step 2.

Step 2 – Compare the ingredient to a control.  In the screening phase it doesn’t much matter what you compare the ingredient to. You are just interested in an effect. After you see an effect then you want to quantify this effect. This is what you do next. Conduct the same test you did in the screening step and compare it to your base formula. If you are testing an ingredient for skin moisturization, take a standard skin lotion and compare it side-by-side with the ingredient. If the test ingredient works better than the control then you’re really onto something. Unfortunately, at this point most ingredients that made it through the first phase will fail to make it past this one.

You might say that this is being too restrictive and that the ingredient might have some synergistic effect with the formula. That’s fair enough so if you want to be even more thorough, create a formula with your ingredient (at some high % level) and compare it’s performance to the same formula without your ingredient. Do this on a blinded basis. If you can tell a difference, then go on to step 3.

Step 3 – Test the formula in real life – Now that you’ve made it past the first two hurdles you’re ready for the final, most significant test. Move out of the lab and test your formula with actual consumers. Give them a sample of the formula with the ingredient versus without the ingredient. Let them try the products over the course of two weeks. Then record their responses. Did they notice any difference? Which product did they like? You can even take lab measurements to quantify any difference but these measurements are mostly only relevant for claims support. If consumers can’t tell a difference but you can measure one with a lab instrument it is much less important than if consumer can tell a difference.

Here, in step 3 is where nearly all extracts fail. They just do not provide consumer noticeable effects. And this is why cosmetic chemists think that extracts are simply claims ingredients in the formula.

Why use extracts?

All of this leads to an obvious question. If they are useless in the formula, why do you use them? This is because they are not useless in the formula. While they don’t have any functional impact, they do have one very important impact…they increase product sales. People want to buy cosmetics that have exotic or impressive ingredients in them. If you go to Amazon.com and search the number one selling beauty products, they are products that contain Argan Oil. Now, if you look at the list of ingredients of those formulas, there is little to no argan oil in the formula.

This means that even though argan oil does nothing in the formula, it clearly helps sell the product. And in the cosmetic industry if you aren’t selling your formula you don’t have a product.

We add extracts because they sell product.



  1. Alexis

    Hi Perry,

    Big fan of the show, and I was looking for some guidance formulating with extracts.

    As a MD here in the US, I totally get your skepticism when it comes to “natural” ingredients (I too share your hatred of pseudo-science, woo, and quackery)

    I think the biggest problem with most cosmetic topical applications of extracts (besides the use of stuff with no strong evidence because it “sounds yummy) is a matter of dosage. Because the fact is there are studies to support the use of many extracts. The problem is one of dose – the extracts in question are typically used in concentrations never seen in commercial formulations, and my guess is primarily one of cost? Am I right in that assumption?

    Take for example licorice root. Several studies have supported topical use of glycyrrhiza glabra extract and the multitude of compounds contained therein for anti-inflammatory effects and melanin-inhibition, as well as cytotoxic/anti-neoplastic applications. Yes, one could isolate each compound and synthesize it, and for pharmaceutical applications, I think that makes sense. But there seems to be enough supportive evidence to support formulating with the extract itself.

    So help me understand – why the heck not??

    1. Perry Romanowski

      Thanks for your comments. Yes, one of the problems with using extracts is one of dose. They are not typically put in formulas to have any real effect. Most extracts are supplied as 1% solutions and used in the formula at 0.1% which means the actual ingredient is in the formula at a level of 0.001%.

      The main reason is that these things are used for marketing purposes mostly. The company would get the same consumer acceptance whether they used an active amount or just a tiny amount because the words on the package could be the same. This is because most compounds, while they can be proved in a lab, cannot be proved in a topical application.

      And an ingredient like the one you cite (licorice root), melanin-inhibition is a drug claim. There are only a few approved skin lightening drugs and until the supplier of the ingredient files a NDA to verify the safety and effectiveness of licorice root, you can’t legally use it to make a skin lightening product.

      In fact, you can’t use ANY ingredient in a cosmetic that would affect the metabolism of skin cells. If you do, you are selling an illegal drug.

  2. Jean Qian

    Thanks Perry for revealing the real functional impact of natural extracts in cosmetics. But just curious, my Chinese friends really like the SK-II products, especially for the facial treatment essence, which claims containing more than 90% Pitera and can make your skin radiant. I think it is like an byproduct of Japanese Sake. So do you believe this extract really works on our skin? Or just for selling its product?
    Also, quite a lot of good selling cosmetics which are made in Japan and South Korea, contain a long list of natural extracts…I am really condused now…

    1. Perry Romanowski

      You should never take the opinions of what people like over evidence provided through scientific testing. SK-II products are probably great for them. I don’t know the line but if your friends like them, they should keep using them. It is highly unlikely that the performance has anything to do with the natural extracts in there.

      Yes, putting a long list of natural extracts on your product list helps the product sell better. That is why they are on there. Not because they are providing any functional benefit.

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