Updated: Feb 16
Skincare is CROWDED these days. With social media we are seeing so many independent brands pop up from skincare enthusiasts, celebrities, and even the large corporations who want to break out into new identities. How do we know what is healthy skincare, and what is just really great marketing?
Let's start with the basics...
What does it mean when we say "science-based skincare"?
Science-based skincare products have been not only tested for efficacy, but are backed by scientific principles about your skin. This is not the same as being endorsed by a dermatologist - think about when you hear that 9 out of every 10 dentists recommend Crest Toothpaste.
Science-based means that the ingredients were designed with your skin's chemistry, anatomy, and function in mind to deliver the greatest possible, and intended outcome of using that product. It sounds like ALL products should be made that way, but not all skincare is created equal. Even those that have the right active ingredients to do the job could also have other additives that can reduce the efficacy of the active ingredient we are trying to get the most out of!
Skin is made up of four layers, each with their own function. We break this down for you below.
The skin cells that make up this layer have a short life of about 30 days, after which they dry out, flatten, and breakdown. This is the layer of our skin that sloughs and helps to create the dust around our houses.
Corneodesmosomes are important to your skincare products affecting the 'SC'. Corneodesmosomes are the protein complexes that help to hold the SC together, which means that these structural molecules have to breakdown before old skin cells can be replaced with new cells from the dermis.* Skincare products that help "desquamation" - term for skin peeling or sloughing - are exfoliants. Exfoliation becomes increasingly important as we age, since our natural desquamation process slows.
We've all seen how many daily exfoliators are available in your regular supermarket or beauty store (Ulta, Sephora). How can you tell what exfoliator will work the best when all companies pay top-dollar for marketing experts to make them all seem effective? Look at the ingredients. For a good quality exfoliator, founded in science, you want to see alpha hydroxy acids (AHAs) towards the top of the list. These acids go by a few names:
AHAs "diminish corneocyte cohesion immediately above the granular layer by detaching and desquamating the stratum corneum"*, which is what we've been talking about! We want to help our skin shed old cells to ensure we are protecting our skin barrier and keeping our skin bright, not dulled by old skin.
Let's compare the ingredients of a common product we probably all had as a teenager against an industry-leading science-based skincare brand.
Neutrogena Deep Clean Scrub (sorry Neutrogena fans, we don't mean to pick on you!) which claims to exfoliate certainly can with salicylic acid which is a BHA, beta hydroxy acid. BHAs are exfoliants too, but they work in a different way than AHAs which is why AHAs are typically preferred for most people who aren't dealing with chronic acne or very oily skin.
BHAs work by permeating the lipid membrane. The SC lipid membrane provides our skin's "main barrier against uncontrolled water loss and invasion of external pathogens"*. This is not to scare you away from BHAs - they absolutely have their well deserved place in skincare - but rather highlight how AHAs and BHAs work differently with your skin. If the intent of exfoliation is to aid in the removal of old cells, AHAs just work more efficiently on the anatomy of our SC by being water -soluble and working to break up those pesky corneodesmosomes protein complexes.
Takeaway on the SC: Our first layer of skin is our barrier, and it's what everyone sees. To ensure your skin is properly permeable and also isn't looking ashen, we need to ensure that our exfoliants contain alpha hydroxy acid (AHA).
PRO TIP: Regular AHA use, or use in high concentrations, can lead to sensitivity to sunlight. As if you needed another excuse to wear your sunscreen everyday!
- End Stratum Corneum (Layer 1), Keep Reading for Epidermis (Layer 2) -
New skin cells - keratinocytes - form at the base of the epidermis, moving up through this layer pushed by a never-ending layer of new cells beneath. Here at the base of the epidermis is also where our melanin is produced, which gives us our skin tone. It is important that these two cells are made in such close proximity to one another because as new skin cells travel upward, they take melanin with them.
Melanin, produced by melanocytes, is what products that will affect our epidermis should be focusing on. Sun exposure and inflammation are environmental conditions that cause melanocytes to produce melanin at a higher rate. Skincare products that focus on regulating melanin production are important to everyone (not just darker skin tones) because melanocytes are sensitive to the aging process.
There are three core products that should be used regardless of age that help to combat the results of the overproduction of melanin.
If you're interested in reading more about free radicals affect on skin, we recommend this article on Free Radicals and Extrinsic Skin Aging. Note that it is definitely intended for an audience with a science background, but we think there are some clear takeaways everyone can easily understand.
- End Epidermis (Layer 2), Keep Reading NEXT WEEK for Dermis (Layer 3) -
*Throughout this article, we referenced a great book called Discovering Cosmetic Science published by the Royal Society of Chemistry in 2020. The RSC is a professional association which publishes over 52 peer-reviewed journals in chemical sciences. If you're crazy about the science of cosmetics, you can buy the book here.
Disclosure: We are not compensated by SkinBetter Science to promote their products - we just believe in these products and have used them ourselves. We do receive compensation when products are purchased in our office; however, the purpose of our blog is NOT to sell product. Our blog is intended only as an educational tool.
THE END OF PART I - STAY TUNED FOR PART II