Saturday, April 27, 2013

Beauty Bullshit: Revlon Eterna 27

Revlon's Eterna 27 is a line of creams that supposedly helps target wrinkles.


Credit for this observation of pseudoscience goes to Rachel, a reader who observed some rather bizarre claims in the Revlon cosmetics employees training guide.

According to Revlon, their "protective telomeric complex [in Eterna 27]... is like a special 'memory' for your skin that continually reminds our skin cells to reproduce and reproduce accurately - helping keep skin looking younger for longer."

It's not clear exactly what this "complex" is. Presumably it is pregnenolone acetate, which they market as "progenitin", an endogenous precursor to a variety of neuroactive molecules including progestagens, glucocorticoids, androgens, and estrogens.


It is worth noting that not only are there no scientific studies indicating that pregnenolone acetate has any effect on wrinkles, there is no evidence that it is even able to penetrate the skin.

So, on to the science! First of all, what are telomeres? 

Your DNA, as we all know, is a series of nucleotides that together form the genes and regulatory regions that provide the unique code that makes each organism. Since DNA is double stranded, these nucleotides pair up, making hydrogen-bound base pairs. There is a lot of information that needs to be encoded in an organism's DNA. The human genome has about 3.2 billion base pairs. If that was stretched out linearly, each cell's DNA would be about two meters long. Since your cells are not two meters long, they need to be packaged up more parsimoniously.

To deal with this problem, DNA is packaged into a condensed structure called chromatin. Being in the form of chromatin keeps long DNA chains nice and small, protects the DNA from damage, binds the DNA to necessary proteins, and helps control gene regulation. All of this essential in order for the cell to work properly. Chromatin can be more or less coiled up depending on what stage the cell is in.

Human chromosomes.
This coiled up chromatin forms the basis of our chromosomes. Humans have 46 chromosomes. At the end of each chromosome is something called a telomere. Telomeres are a series of repetitive nucleotide sequences that do not code for anything.

Glowing telomeres!
Why do we need telomeres?

Every time your cell divides, you lose a little hunk at the end of your chromosome. When DNA polymerase, the enzyme that replicates DNA, does its job, it can only go in one direction. Your DNA is not symmetrical. We talk about DNA in terms of 5' at one end and 3' at the other. DNA polymerase will only go from 5' to 3' because it needs to act on the 3'-OH of the existing strand to add nucleotides.

DNA replication starts at the center of a DNA strand. One DNA polymerase can go straight through without any problems, because it is traveling from 5' to 3'. This is called the leading strand.

The other strand, though, is more difficult. Instead of traveling straight down the strand, the DNA polymerase works to create a series of short fragments called Okazaki fragments. Sequences of RNA are used as primers a little bit ahead of the initiation site, letting the DNA polymerase start there. Because these fragments are not connected, there is a little bit of excess processing needed to make the strand useful.

Enzymes come and help change those RNA primers to DNA, connecting the Okazaki fragments. However, in order for this to happen, there must be a DNA strand before the primer. The very last RNA primer does not have that. Thus, it is destroyed. As a result, some of the DNA code is destroyed every time DNA is replicated.

If we had useful DNA going straight from one end of the strand to the next, that would mean that you would lose important information when replicating cells. Telomeres protect the DNA code by getting lost-- instead of losing crucial genes, we lose nonsense gibberish.

How do telomeres relate to aging?

Some people hypothesize that telemeres are closely related to the aging process. Because a little bit of telomere is lost at each cell division, individuals who are older have shorter telomeres than individuals who are younger. This fact has led some people to hypothesize that the reason that we age is because our telomeres are getting shorter.

Unfortunately, this explanation does not fit well with the scientific data. For example, rats with dramatically shortened telomeres do not have shorter lifespans. It's also worth noting that rats have super, ridiculously-long telomeres. If the telomere theory of aging was a major component of the story, rats would live much longer than we do... but they don't. Even more damningly, human telomeres can sometimes be maintained in length, and approximately 0% of those people who this happens to are Benjamin Button.

Who knows what is going on with his telomeres.
It also is an explanation that doesn't make a lot of theoretical sense. Telomeres are a code of seriously random nothingness. It doesn't code for anything. It doesn't promote anything. It doesn't regulate anything. It shouldn't matter that they are getting shorter until they reach a certain critical point.

Worse still, telomeres have never been proposed as a mechanism associated with wrinkles. Being less likely to die and being less likely to have crow's feet are hardly analogous.  The idea that shortened telomeres cause wrinkles is absolutely the textbook example of the adage "correlation does not equal causation". To quote Dr. Ron Rosedale, "The telomere theory as a cause of aging was hotly debated over a decade ago in many biology of aging conferences where university researchers got together to discuss their latest findings. Now, this is barely discussed outside of pseudoscientific circles."

Even if telomere protection was a good anti-aging mechanism, we still wouldn't want to implement it. We actually do have the technology to lengthen telomeres, and we have done so in mice. We don't do it in humans because it is a terrible idea. Introducing enzymes that help protect telomeres dramatically increases one's likelihood of getting cancer. If this process was actually occurring in all of your cells, dying of cancer would be a near certainty.

Cancer cells
Now that we have addressed the conceptual problems with telomere anti-aging products, let's go back to the specific claim that Revlon makes: This "protective telomeric complex... is like a special 'memory' for your skin that continually reminds our skin cells to reproduce and reproduce accurately - helping keep skin looking younger for longer."

That makes literally no sense. The "protective telomeric complex" name sounds like they are saying that the product will prevent telomeric shortening, which is problematic for reasons I have already outlined. But telomeres have NOTHING TO DO with causing your skin cells to reproduce (and if you were using a telomere shortening theory of aging, you wouldn't want them to reproduce!), they have NOTHING TO DO with the accuracy of DNA polymerase, and even if they did, that would have NOTHING TO DO with keeping your skin young-looking. This claim is bullshit, plain and simple.

If you have any beauty claims you want researched in future Beauty Bullshit blogs, feel free to leave them in the comments below.


  1. Marvelous! I'm beginning to suspect pictures like the glowing telomeres are why I like science-- things are so much cooler in bright colours!

  2. I'd be interested in your take on the Algenist line of products. I've been using the Overnight Restorative Cream and the Regenerative Anti-Aging Moisturizer for over a year and my 41 year old skin loves them. They explain their stuff with a lot of science-y mumbo jumbo about seaweed or something. I don't understand it but still love it - despite the ridiculous pricetag. Thanks!

  3. Love the Beauty Bullshit posts! Ever think about looking at the Fat Girl Slim products? They seem to be based on pseudo-science and buzzwords at best but who knows maybe they are legit! I know a fab scientist (YOU) that could clarify that for her adoring public (ME).

  4. I had a lecture on telomeres and aging at uni! It would have been maybe five years ago now? So I'm sorry if this is too vague to be of any help.

    From memory, telomere reduction does affect aging, but it affects the aging of the cell line. Every cell divides into two at the end of the growth cycle, and if that kept happening indefinitely then tissue would keep increasing in mass to the point where it's a detriment to the organism. Single cells do die for a variety of reasons, everything from damage from the environment to targeting from the immune system, but one way this growth is controlled is by telomere shortening which prevents eight million generations of the one cell x millions of cells to begin with. Like you said, telomeres can be repaired and telomere reduction can happen at different rates within otherwise identical cells, which is why you don't get every cell in a tissue being unable to continue the growth cycle at the exact same time (though that's a neat sci-fic-horror premise, which is probably why I remember so much of this one genetics lecture).

    So, telomere reduction has been linked to aging of cell lines, and the aging of cell lines has been linked to changes in tissue. But... yeah, the beauty industry has picked up these two concepts and run with them :/ But thank you for writing this post, it's a really great breakdown of the lack of sense these products make.

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  6. Once again - a wonderful blog entry. I like your scientific approach, your 'bewildered humour' and your graphic layout. I wish I was as good at the graphic bits - my blog is just words :-( Anyway, as I said in another comment, I will link to this article from my blog and also mention it on my facebook and twitter feed. I have felt lonely out there in my attempts to educate people on facts vs marketing hype, so it is wonderful to have you as company :-) It's very unfortunate that facts are not as sexy as marketing hype and BS...

  7. Eterna 27 actually works and I swear by it, so did actor George Burns, and he had skin like a baby's butt 'til the day he died. After using it for three days, I could tell that my skin looked much better.


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