Stem Cells in Skincare

What are stem cells?

Stem cells are undifferentiated cells which have the potential to differentiate into specialized cell types (such as specific types of skin, muscle, blood cells, etc.). They are capable of multiplying indefinitely, as long as the person is alive. Yet, stem cells in the human body undergo aging, and as we grow old, our body gradually loses its capacity to renew tissues.

Stem cell – based skincare products

For the beauty-conscious, aging means that the renewal of skin cells slows down (due to the aging of our skin’s stem cells). Wrinkles start to appear and wounds or scars take longer to heal. The cosmetic industry has now come up with a new solution: To use stem cell-based products to stimulate our own skin’s stem cells to regenerate and live longer.

Not all stem cell-based products are the same. In fact, their ingredients vary greatly. Here are the different types of active ingredients in products which are marketed as “stem cell-based”:

1.       Plant-derived stem cell extracts

Plant stem cells are mainly found in the tips of the shoot & roots, and in the stems of a plant. Just in case you would like to know. If I didn’t interpret wrongly from this Yahoo article, L’Oreal’s Age Perfect Cell Renew range contains plant stem cell extracts.

2.       Human-derived stem cell extracts

Don’t worry, they don’t use embryonic stem cells. Some products use adult human stem cells. One famous brand, Lifeline, which has been mentioned in several beauty articles on the Internet, uses stem cells developed from unfertilized human eggs. Now, would you like to apply some cream made of unfertilized eggs donated by an anonymous lady from somewhere out there?

3.       Proteins secreted by stem cells

Meaning, the stem cells themselves are not used in the product. Stem cells are grown in a liquid medium, and that liquid medium bathing the cells is collected. To be honest, I don’t know of any particular brand of product that uses this, but I do know that the method has been patented.

What is the science behind stem cells in skin care?

I tried to search for scientific literature studying the use of stem cells in cosmetic products and came up with ZERO results. I repeat: ZERO results, whether it's for plant/animal/human-derived stem cell products. Sure, some companies do mention on their websites that their product has shown great results in a study, but then these results are not made available to the public or even to the scientific community. Sounds rather suspicious, don’t you think?

Let’s think about the plausibility of their claims. Take a look at a statement from Lifeline (taken from the Lifeline website):

“Scientists at Lifeline Skin Care discovered that human non-embryonic stem cell extracts can renew skin -- by replacing old cells with healthy new ones.”

If scientists had truly found a way to reverse aging (i.e. to turn the old cells into healthy new ones), this would be the greatest medical breakthrough of all time. This technology would be applied in every field of medicine possible – to get younger & healthier brains, bones, muscles, etc. We would have discovered the Tree of Life, the fountain of youth. We would live forever, and never grow old. Erm… Does that sound a little less convincing now?

In the end, I believe that “stem cell-based skincare products” sound very science-y, very high-tech, but that’s all just part of marketing strategy. Somehow, stem cells have evolved over the years from being an ethically controversial issue to becoming a mysterious, sort-of trendy promise for the future of medicine (and now, cosmetics). But before we spend a fortune on scientific-sounding products, let’s do our research properly to differentiate a hoax from the real deal. 

Toner, serum, emulsion, etc.

Before I got married, my skincare regimen consisted only of a facial cleanser. Oh, and an antibiotic cream for acne when I was in my teens. But ever since my hubby went to Korea and bought lots of skincare products for me, I've tried using many different products. (Otherwise they will be wasted, right?) J

For someone who’s only known what “cleanser” was, seeing all the different names of the various types of products was a confusing experience for me! These are some of the products that I commonly encounter:

Cleanser:

I guess everyone knows this! J Used for washing your face with.

Toner:

For use after cleansing, usually to remove any excess oil or makeup residue, shrink pores, and restore the pH balance of the skin.

Apparently, there is some controversy about toners nowadays, since many dermatologists and beauty editors believe that toners are not an essential part of a skincare regimen, unless you have extremely oily or acne-prone skin. (I read that here.)

Softener:

The term “softener” is more commonly found in Japanese / Korean products. Softeners are basically toners but as the name suggests, they are meant to hydrate the skin instead of drying it out.

Serum:

Serums are products containing active ingredients such as vitamins / antioxidants in high concentrations and are designed to penetrate into the deeper layers of the skin. Serums are meant to be applied after toner, and before moisturiser. A small amount (a few drops) would be sufficient for the whole face.

Essence:

A lighter version of serum (less concentrated).

Emulsion:

Also known as lotion, this is a moisturiser with a liquid consistency. It’s not as “heavy”/oily as creams.

Cream:

A “heavier” moisturiser with a creamy texture.

These are just the basics! I sometimes encounter other less heard-of terms which are used to describe specific products (or worse, sometimes no English words on the products), so when I don’t know how to use a product, Google is my friend! :P

Alcohols in skincare products

Today’s topic was suggested by my lovely housemate, WL! J

Should we avoid skincare products containing alcohol? There are already many articles out there on the internet discussing and debating this issue. Many articles also talk about “good” alcohols and “bad” alcohols for the skin.

Before we explore this topic further, let’s do a short revision of some ‘A’-level organic chemistry:

Chemical structures of alcohols

In chemistry, the term “alcohol” refers to any of a class of organic compounds characterized by one or more hydroxyl (−OH) groups attached to a carbon atom of an alkyl group (hydrocarbon chain, represented as R in the drawing above). (Definition from Encyclopaedia Britannica.)

The alkyl group, R, can vary in length from short hydrocarbon chains (e.g. ethanol, isopropanol) to long hydrocarbon chains (e.g. stearyl alcohol, cetyl alcohol).

Short chain alcohols

1.       Ethanol (also known as ethyl alcohol. It is also the major ingredient in denatured alcohol or SD alcohol.) This is the alcohol that we drink!

  

2.       Isopropanol (also known as isopropyl alcohol)

Short chain alcohols are the alcohols which are commonly said to be “bad” for the skin as they can disrupt the skin’s protective barrier and dry up the skin. In my opinion, these are not necessarily bad ingredients as they can help to dissolve active ingredients in the product & also help increase the absorption of active ingredients by the skin. (See my previous post on skin penetration enhancers.) But if you have dry skin or eczema, then you may want to avoid products containing these alcohols which can worsen the dryness.

Long chain alcohols

Due to their long hydrocarbon chains, long chain alcohols tend to be greasy/waxy and make good moisturisers. Hence, many articles call them the “good” alcohols.

1.       Cetyl Alcohol 

2.       Stearyl alcohol 

3.       Cetearyl alcohol (which is a mixture of long chain alcohols, mainly cetyl and stearyl alcohols)

4.       Lanolin Alcohol (also known as wool alcohol, produced from lanolin or “wool fat”)

A word of caution though: some people may be allergic to lanolin.

Some other alcohols…

Besides short-chain and long-chain alcohols, some other ingredients also contain “ol” or “alcohol” in their names. Here’s just a few examples:

1.       Glycols (propylene glycol, butylene glycol), glycerol (also known as glycerin)

 

Chemical structures of propylene glycol and glycerol

I suppose most people wouldn’t think of these ingredients as alcohols, but I shall include them here anyway since they are commonly found in skincare products too. LOL. Glycols have 2 –OH groups in their chemical structure, while glycerol has 3. These compounds are humectants, which bind water and help moisturise the skin.

2.       Phenoxyethanol

3.       Dichlorobenzyl alcohol (also used as an antiseptic in Strepsils lozenges!)

 

Chemical structures of phenoxyethanol and dichlorobenzyl alcohol

Both phenoxyethanol and dichlorobenzyl alcohol possess antibacterial activity, so they are sometimes used as preservatives in skincare products.

4.       Vitamins such as retinol (vitamin A), calcitriol (vitamin D), α-tocopherol (vitamin E)

From the different examples mentioned above, we can see that “alcohols” describes huge class of compounds, and different alcohols can have very different effects on our skin. I hope that this blog post has given you a better idea of some of the different types and functions of alcohols used in skincare products. J

Update: My snail cream trial

In my previous post on snail creams, I mentioned that I started my own little trial of products containing snail secretion. Well, it's been 4 weeks, and here are the results of my little "experiment" (albeit a very non-scientific one!):

  

Product: It’s Skin Prestige D’escargot special trial kit

Regimen: 

Morning: Toner & emulsion

Night: Toner & cream

(Disclaimer: This is not an advertisement for the brand! It just happens that this product is what my hubby brought back from Korea for me.)

In my Google search, I didn’t manage to find the percentage of snail secretion filtrate contained in these products. I only came across this description of the cream:

“First class luxurious cream contains mucin (snail mucus), the ingredient with superior cell restoration, moisturization, and skin trouble relieving effects, and EGF (epidermal growth factor), through the combination of which creates a synergy effect to regenerate damaged cells, the fundamental cause for skin aging.”

Oops! So I didn’t realize that the cream contains EGF (epidermal growth factor) as well… That’s another ingredient which is also claimed to repair damaged skin. Hmm. This could present a confounding factor to the results…

Without further ado, here are the results!

Under-eye area:

Under-eye area at baseline, 2 weeks and 4 weeks

Puffiness seems to have decreased. Fine lines under my eye are still present after 4 weeks, but looks slightly improved. (Honestly, I can’t tell by looking in the mirror, but the pictures seem to suggest an improvement.)

Being the skeptic that I am, I was genuinely surprised by the improvement! And happy too, of course.

Hyperpigmentation:

Hyperpigmentation on left cheek at baseline, 2 weeks and 4 weeks

No noticeable difference in the hyperpigmentation spot on my left cheek.

Old chicken pox scars:

Chicken pox scars on right cheek at baseline, 2 weeks and 4 weeks

No noticeable difference in the old chicken pox scars on my right cheek.

Conclusion:

From my own limited experience, I have come to a conclusion that snail cream is definitely not the “miracle cream” it is commonly advertised to be. However (at least for me), it did help to slightly reduce the appearance of fine lines/wrinkles.