In my recent post about cosmetic chemists and marketing I made some assertive claims about the effectiveness of Green Tea extract. Basically, I said it doesn’t do much in a formula and is added just for the marketing story. And I went on to complain about scientific organizations propagating what qualify in my view as marketing stories.
The science strikes back
So, I tweeted my opinion and I received a response from one of my fellow beauty science communicators (Lab Muffin beauty science) directed my attention to some research published in the Journal of the American Academy of Dermatology. It was on Green Tea extract and how it can protect against UV damage. But that’s not all, there’s more!
A search of Google Scholar for “green tea extract skin topical review” since 2018 showed a whopping 10,400 results. Of course, not all of the results are related to cosmetics (many are cancer research papers) but and high percentage likely are.
So, it makes me wonder, am I too cynical or also, am I just wrong?
Skepticism or Cynicism of an industry chemist
To the question of cynicism, there is a fine line between cynicism and skepticism. I see the differences as follows…
A cynic holds a belief that will not change no matter what evidence is provided.
A skeptic holds a belief that gets updated when new evidence warrants updating.
Cosmetic scientists should be skeptics not cynics. And they should be willing to say that a belief they previously held is wrong if new data that they become aware of shows they are wrong. However, the default position for any claim should be one of disbelief. Cosmetic science is complicated especially when you are looking at the way a compound or system affects people’s skin. Coming up with generalizations is just really hard.
But how do you get away from being a cynic? You try to keep up on all of the available research. Google Scholar, industry journals and magazines are all great places to do that.
Of course, there is way more information published on too many topics that you can’t possibly keep up with every subject. And there are significant problems with a lot of this research.
Problems with research
Truth imbalance. It takes almost no effort to make a claim about the effectiveness of an ingredient. It takes vastly more effort to expose flaws or debunk a claim.
Poorly designed studies. In addition to poor design much of the research related to cosmetic ingredients is not relevant to real life conditions. What happens in a contrived lab setting is not the same as what happens to consumers using formulated cosmetic products.
Exaggerating results. This happens a lot with supplier studies. They’ll purposely pick easy targets to compare their raw material to so it will show impressive, statistically significant results. But is it something a consumer will notice or benefit from? Not usually.
Publication bias. There’s a publication bias in favor of publishing positive studies. Studies that are negative are rarely published.
Motivated researchers. And it’s hard to get funding for this type of research, so it is usually bankrolled by a company that makes an extract or ingredient. Also, some researchers embrace the naturalistic fallacy. They’re motivated to find examples in nature that are superior to any synthetic alternatives. Some researchers are motivated to find results in favor of what they want to be true.
Does green tea “work”?
Now, I haven’t gone through the 10,000+ articles on green tea and skin, but let me review my claims.
“Is green tea a potent antioxidant? Maybe but you’re not going to use it in place of BHT.” - That green tea is made up of antioxidants is supported by research. But is it “potent”? What does that even mean? Where does green tea extract fall in the range of other antioxidants out there? I couldn’t find an easy answer to this but compared to other teas, green tea scores the highest on the FRAP scale. But the Epigallocatechin-3-gallate in it is purported to be unstable so how useful is that in formulating?
“Does green tea contain catechins, tannins, and caffeine? Sure, but so what? There’s no benefit to having these things in your formula.” From the study above I was directed to, they extol the UV protection benefits of green tea extract. But that was in a 5% water/alcohol solution. Where is the evidence that putting it in a cosmetically sellable product continued to show effects?
“Does green tea reduce sebum production? No. Not in any consumer noticeable way anyway.” - This study would dispute my dismissal of its anti-sebum effect but this study also has no control and 10 subjects! They don’t even ask the panelists if they noticed a difference so who knows if it works in a consumer perceptible way. Maybe it pans out but this is preliminary research.
“Does it sooth & reduce redness, alleviate puffiness and inflammation and protect skin from free radicals? No, no, no.” I was probably too dismissive here and if you want to see a review of the latest research on green tea extracts go here. I’ll just add that the research cited is not helpful for formulating.
Helpful for formulating
Formulators are trying to make the most effective products they can while balancing costs. The problem with all of this research is that it is not trying to find the optimal ingredient, it is trying to prove that an ingredient has some effect. So they compare it to no treatment or they compare it to a poor placebo cream. But consumers are exposed to properly formulated products. They should compare the ingredient to occlusive agents and silicones and organic sunscreen compounds and all the other standard ingredients that are used for the claimed benefits of green tea extract.
Let’s say green tea has all the benefits claimed.
It’s still going to be more economical to use a standard ingredient to get the benefit, then use a tiny amount of green tea extract to make the claim.
The green tea extract in your formula is not doing anything. It’s a pixie dust ingredient that supports the marketing story. That’s it.
Maybe some things are true under specific conditions. My complaint is that it creates an impression among consumers of a thing that is false. It’s highly unlikely that green tea extract in their product is making the cosmetic work better. This is the story product marketers want to sell. Scientists shouldn’t be helping with that mission because it isn’t true.