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The Curly Girl Method – what’s the science? episode 170


On today’s episode of the Beauty Brains we cover beauty questions about

  • Shampoo and what it does to hair color
  • Whether collagen works in skin care products
  • The Curly Girl method of treating hair

Beauty Science News

Is there asbestos in J&J baby powder? 

Reuters says that J&J was selling product with asbestos in it. J&J says they weren’t. Science can’t answer that question but it can answer the question of whether you should be afraid baby powder is causing cancer. It isn’t.

Unilever Sues Target

Unilever, the parent company of the spa skincare brand Dermalogica, has filed a lawsuit against the major retailer Target in the United States, alleging that they are not authorized to sell their product but they are obtaining it and selling it anyway. Even worse, the complaint states that Target is removing the holograms and quality control tags that let the consumer know the product is authentic.

Do you think Unilever is justified in filing this lawsuit? – Tweet it to us @thebeautybrains

Beauty Questions answered

Question 1:

Lily says – Love the podcast, I am so glad you are back. Keep up the good work!

I would love to know the chemistry of shampoo on colored hair.

  • Why does washing hair strip off the color on colored hair?
  • What ingredient(s) make the color safe shampoo effective ?
  • Does purple/blue shampoo keep your blonde highlights blonde?
  • How exactly does it work and will it work if it’s old highlights ?
  1. Washing removes color from colored hair because it opens the cuticle, swells the hair and allows the color to leach out.  Explain how hair color works.
  2. Color safe shampoos don’t really have an ingredient to make them less stripping, they have less detergent so they will nominally remove less color. But the reality is that they don’t work too well. If you tested products side by side, you wouldn’t see much difference in stripping of color.
  3. Blue/purple color is meant to reduce brassiness
  4. Essentially a small amount of the violet or blue dye is absorbed into the hair and that offsets any brassiness color.

Question 2:

Duilia asks –  Does collagen really work in topical skin products?

Collagen does a lot of things in the body but for skin, in addition to being the scaffolding, it promotes elasticity, flexibility, it protects the lower layers of skin and the body. It’s produced by the body in many forms but for skin it comes in these tiny fibers that are meshed together to form the skin structure. It’s an important protein

Now that brings us to the main question, why is collagen put in skin products and does it really work?

There are really two reasons cosmetic makers put collagen in skin products. The main reason is because collagen is an appealing ingredient to consumers which helps differentiate the product from all the other moisturizers out there and convinces people to buy it.

The logic behind using collagen in formulas goes something like this.

Skin is made of collagen
As we age, our skin produces less collagen
The lack of collagen is one of the things that leads to sagging skin and wrinkles
So adding collagen back to skin will refresh the skin and make it look young again

It’s worth pointing out too that the type of collagen used in skin products is called hydrolyzed collagen which is collagen protein broken down into a more simplified structure. It’s nothing like the collagen is found in skin.

But we don’t want to be too dismissive. So, let’s dip into our toolbox to take a more detailed look at collagen in topical treatments. Whenever we try to decide whether any anti-aging ingredient works for the skin it makes sense to ask the three “Kligman questions” that we ask. Kligman was a famous research dermatologist who did a lot of pioneering work in the field specifically related to cosmetics.

The first question is Based on the chemistry of the ingredient, is there any scientific mechanism that could explain why it would work?  Well, we’ve already talked about that and while the way it’s done in cosmetics is dubious, there is some scientific theory upon which collagen could improve the skin. If bits of the collagen protein could get down to the collagen scaffold and then get incorporated into it, that might provide a benefit.

So the second question is “Does it penetrate to the part of the skin where it needs to be in order to work?”  If hydrolyzed collagen was to work it would have to be able to penetrate into the dermis which is where the majority of skin collagen is. Unfortunately, the molecule is too big to penetrate so for the most part it does not. Instead it stays in the stratum corneum and may provide some moisturization but that’s about it.

And then the third question is “Are there peer reviewed, double blind, placebo controlled studies demonstrating the ingredient really works when applied to real people?”  None that I could find.

So, the bottom line on topical collagen is that even though it has been used in moisturizers for years as an antiaging ingredient, there is little scientific evidence that would support using it for such purposes.

No Duilia, topical collagen doesn’t really do much in skin beyond providing a little bit of moisturization.

Question 3: (Audio question)

CG method says stay away from…

We could do a whole show on this method but we’ll try to tackle some of the specific claims.

First, there is the claim that sulfates shampoos are too harsh and you should use sulfate free products or conditioners only.

Next, there is the claim you should avoid silicones or non-water soluble silicones. There is also the claim you should avoid parabens and fragrance.

Finally, there are claims about how you should style your hair. Don’t use heat, don’t comb hair, and don’t use a towel.

So, let’s start with the first claim. Are sulfate shampoo too harsh and are sulfate free products better? Not really but it depends.

Then there is the second part of the question. Protein sensitivity.  According to Jasmin, the CG method says too much protein makes hair dry brittle and too much hydration makes hair soft and limp. – This is a misunderstanding of how protein treatments affect hair.

Finally, to the question of whether these ingredients be used as an indicator to find the right products for your hair?

No.

Curly Girl method:  https://www.youtube.com/watch?v=NDofglvTFx8

Curly Girl method 2 : https://www.youtube.com/watch?v=_6V6a_yQk-o

Next Time…

We’ll look at the question whether the ingredients used in cosmetics are safe to use and what might be the side effects?

Sign off:

Thanks for listening. Hey if you get a chance can you go over to iTunes and leave us a review. That will help other people find the show and ensure we have a full docket of beauty questions to answer.  

Speaking of beauty questions, if you want to ask a question click this link

or record one on your phone and send it to thebeautybrains@gmail.com

We prefer audio questions because it sounds better on the podcast.

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{ 9 comments… add one }
  • Marie January 22, 2019, 12:43 pm

    I am so happy you are back! So I need some help with sunscreens. I am worried about long term effects of « chemical » sunscreen on my hormones and the « mineral » effecting my hairline. I swear my hair thins out when I use « mineral » creams. I do have an autoimmune problem. Thanks!

    • Perry Romanowski January 24, 2019, 4:06 pm

      That sounds like a medical issue which we can’t really help with. There are no proven long term problems with using “chemical” sunscreens so if you are worried about using the mineral ones, stick with the “chemical” ones.

  • Katie Cilluffo January 23, 2019, 10:26 am

    I followed the Beauty Brains site before you took a hiatus and have the lead/lipstick book as well. Glad you’re back in business. That said, while podcasts are popular, there are those of us who prefer to read rather than listen. (Quicker skimming, more privacy, hearing impaired, etc.). Was very interested in the curly girl info, but not interested in listening to a long podcast. Would LOVE if transcripts or summaries were available instead of just podcasts. Thanks!

    • Perry Romanowski January 24, 2019, 4:05 pm

      Thanks Katie – we’ll figure out some way to get the transcripts posted. At the moment it makes it too long on Overcast to put the whole transcript on the blog. But I’ll get it figured out.

  • Jennifer Younis January 24, 2019, 8:17 am

    What are your thoughts on dark hair colors? I believe the American Cancer Society had indicated that dark hair colors have caused bladder cancer – in mice. I know we aren’t mice, but I would like to know your take on this.

    SO GLAD YOU ARE BACK!!!!

    Thanks!!

    Jen

  • Linn January 24, 2019, 3:46 pm

    oh, hi!

    I thought the blog was closed so totally accidentally I just came by to check things (just in case) and I’m so glad that there are new posts!

    I missed you, guys 🙂

    xo

    L.

  • Katina February 26, 2019, 10:22 pm

    I would love some hair science charts… specifically a list of humectants that ranks their hygroscopicity. And also a chart of silicones for hair that are hardest to remove or if that doesn’t exist which have the thickest viscosity/most tenacious coating effect.

    Thanks!!

    • Perry Romanowski March 1, 2019, 6:09 pm

      This type of chart doesn’t really exist and if it did, that wouldn’t necessarily tell you anything helpful because whether something is easily removed or not depends much more on the entire formula, not the specific ingredient used.

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