SkinCeuticals C E Ferulic Review

There’s really no need to go into great detail about this very basic component. Oddly enough, applying massive amounts of water onto the skin surface doesn’t actually hydrate – contrary to popular belief. It is that magical balance when hydrating components seeps under the skin’s surface is when we start to see benefits.

The other important thing to note is – when a product’s main component tends to be water – there can be issues of bacterial contamination or growth. Unless there is some ingredient that may counter this within the formulation stability – such as a chelating agent.  And in this case, there are none.

Bottom line: Water is neither here nor there.  But if this mask is mainly JUST water with a tiny bit of ACTUAL ingredient – well then are we truly getting the most bang for our buck?

Also known as Diethylene Glycol Monoethyl Ether, ethoxydiglycol is often used as a solvent in skincare products in order to dilute a thick formulation.

Bottom line: Decreasing agent used to dilute the viscosity (or thickness) of a potential solution. Not useful in the overall effect toward its claims.

15% L-ascorbic acid

Ascorbic acid (or vitamin C) is the star of the serum.  It’s what makes the science behind the benefits really resonate.  It is the most plentiful antioxidant in human skin and has been known to form a group of enzymatic and non-enzymatic antioxidants; coexisting to protect the skin from reactive oxygen species (ROS).  

This is what we know about vitamin C as a photoprotector:

• Water-soluble and functions in the aqueous compartments of the cell
• Protects the skin from oxidative stress by neutralizing the free radicals
• Its oxidized form is non-reactive
• Exposure to UV light reduces the availability of vitamin C in the skin.

In addition, it provides the following:

• Anti-aging effect:  Essential for collagen biosynthesis
• Replenisher of vitamin E
• Anti-pigmentary effect

Vitamin C has many active forms, with L-ascorbic acid as the most biologically active.  L-ascorbic acid is a hydrophilic (water-loving) and unstable molecule.  As a result, this form incurs poor penetration into the skin because of the hydrophobic (water-repelling) character of the stratum corneum (skin layer).

Therefore, in a 2001 study concluded that by reducing the acidity of L-ascorbic acid to a pH below 3.5; it improved both the stability and permeability of the compound.  And in 2005, a study concluded that the addition of ferulic acid helped in promoting the stabilization coupled with a pH below 3.5.

Let’s not forget the other active forms and derivatives:

• Ascorbyl-6-palmitate (stable at pH 6)
• Magnesium ascorbyl phosphate (MAP): Stable at pH 6.  Most stable and easily absorbed into the skin

• Disodium isostearyl 2-0 L-ascorbyl phosphate
• Ascorbic acid sulphate
• Tetraisopalmitoyl ascorbic acid

We also know that in order for vitamin C to provide the most biologically significant change within the skin, it must be at 8% or higher, depending on the formulation.  In fact, that same 2001 study determined that a concentration above 20 percent does not increase its biological significance; with data pointing to potential development of irritation.

Bottom line:  Vitamin C is a potent antioxidant; with L-ascorbic acid being its most biologically active form when combined with ferulic acid, stabilized at a pH above 3.5, and formulated at a concentration up to 20% (ideally 10-15%).

Glycerin (or glycerol) is one of the oldest humectant agent (water-attracting) ingredients used to assist in hydrating and moisturizing the skin surface. The idea of moisturizers and emollients are not only used to smooth the skin but to provide a defined supple appearance after repeated use.

A 1993 study evaluated the influence of glycerin, water, and various other skin mechanics to clarify the effects of short-term influence. The study showed that the utilization of these skin mechanics induced significant changes in the mechanical properties of human skin in vivo even AFTER 10 minutes of application.   

However, a 2001 study evaluated the influence of a cream containing 20% glycerin and whether it affected the skin barrier function during repeat application. Yet, the study failed to show an influence of glycerin on human skin with respect to TEWL (transepidermal water loss) and skin sensitivity.

Yet, time and time again, glycerol has been evaluated for its role in skin hydration, cutaneous elasticity, and epidermal barrier repair. In fact, glycerol has a tendency to accumulate within the entire thickness of the stratum corneum. A review in 2008 concluded that glycerol’s three hydrophilic hydroxyl groups have the ability to bind and retain water, thus providing enhanced skin hydration.

Bottom line:   Glycerin is a humectant agent. Historically used for over 50 years in cosmetics to provide hydration and moisture to the skin.

Propylene glycol (also known as propanediol) is corn-derived.  This ingredient is often used as a moisturizing agent or humectant. Since the ingredient list does not mention which particular form is used within the formulation – I’ll go ahead and supply information for both.

First, 1,2-propanediol (propylene glycol) has been flagged for a number of safety issues – with the most common being skin irritations and even carcinogenic but somehow does not fall under the scary toxic category of no-nos.

However, both ingredients can be used safely at low dosage/concentration levels.  But since the list does not indicate the actual concentration of propanediol (nor its actual true form) – I would keep this in mind in terms of caution.

Bottom line:   Moisturizing agent but may cause skin irritations depending on the concentration level – which is unknown.

Laureth-23 is an alkyl polyethylene glycol (PEG) ether which functions as a surfactant, skin-conditioning agent, fragrance ingredient, and emulsifier in cosmetic products.  

No science-based research could be found as it relates to skin-specific benefits unless we consider trade names and vendor available information per some of the following:

• TEGO® Alkanol L 23 P:  Emulsifier. Manufactured by Evonik.
• PEL-ALC™ LA-23:   Emulsifier and solubilizer that is compatible with almost all other surfactants.  Manufactured by Ele Corporation.  
• HETOXOL LA-23:  Solid solubilizer with a recommended usage level of 0.5-5%.  Manufactured by Ethox Chemicals.
• Brij™:  Solubilizer, dispersant and wetting agent in solid form that is used in hair care, toiletries, perfumes, and fragrance applications.   Manufactured by Croda.

Based on the CIR panel assessment, laureth-23 is deemed safe.

Bottom line:  Laureth-23 functions as a surfactant, skin-conditioning agent, fragrance ingredient, and emulsifier in cosmetic products.

Phenoxyethanol is a preservative used to inhibit the growth of microorganisms in cosmetic products.  Generally, a product formulated with high water content (is in this situation) is prone to the growth of microorganisms unless certain precautions or ingredients are added to thwart such problems.

However, overuse of preservatives within a formulation has also been shown to lead to increased incidences of contact allergy.  Therefore, adding these ingredients poses the question of whether it is truly worth it.

Current concentration use in cosmetics based on a CIR assessment has indicated that phenoxyethanol may be used at a range of ≤ 0.0002% to 1%.

Bottom line:   A preservative used to thwart the growth of microorganisms in high water content formulated products.  No real benefit to claims with potential for skin irritations.

1% alpha tocopherol

Tocopherol is the most prevalent form of vitamin E in plant seeds and products derived from corn, sesame seed, sunflower, olive oils, and a plethora of nuts.

Most of the tocopherols are reported to function in cosmetics as antioxidants or skin conditioning agents.  In fact, a 2003 study, evaluated whether the combination of topical vitamin C and E was better for UV protection to the skin than an equivalent concentration of each – alone. The study concluded that each (in their own right) were significant antioxidants in the protection from skin damage. However, the combination of both C and E provided superior synergy against the likes of skin cancer and photo-aging. Further detailed information regarding tocopherol as a major lipid-soluble chain-breaking antioxidant of membranes and an important cellular protectant against oxidative damage was provided in a 2014 CIR safety assessment.

It is also interesting to note that in 1999, a study found that topical vitamin E applied on scars provided no benefit (in 90% of the cases) to the cosmetic outcome of scars after skin surgery.  And it even noticed that 33% of the patients treated, developed contact dermatitis to the vitamin E.

Overall, tocopherol is the predominant form of vitamin E in human and animal tissues, and it has a high bioavailability. The CIR safety assessment recognized that tocopherol has some absorption in the UV range. However, it was noted that according to animal and clinical testing, tocopheryl acetate was not photo-allergenic or phototoxic.

Bottom line: Strong antioxidant capacity. Best if formulated with Vitamin C ingredients but may be a potential for dermatitis.

Triethanolamines (TEA) are used as wetting agents in shampoos, lotions, creams, and other cosmetics. TEA may often be used as a preservative in cosmetics as well. But most importantly, TEA functions as a surfactant or pH adjuster and often as a skin-conditioning agent.

However, as with most preservatives, there is always the likelihood of developing an allergic reaction. TEA is certainly one that isn’t removed from that category. In fact, in a 2012 study, a slew of ingredients known for allergic reactions was tested on 147 patients. Of those ingredients, it was concluded that TEA was one of the more frequently associated ingredients for allergic contact dermatitis.

Nerd note: During my days while working on the bench (lab) – I often used TEA in a buffer (solution) and then slowly adjusted the pH of that either with some sort of acid or base accordingly. The TEA was often varying concentrations but I remember it having a very strong smell.

Bottom line: Preservative that functions as a surfactant or pH adjuster and often as a skin-conditioning agent but offers the potential for allergic contact dermatitis.

0.5% ferulic acid

Ferulic acid (4-hydroxy-3-methoxy cinnamic acid) is a phytochemical commonly found in vegetables and fruits.  It has been shown to have antioxidant properties and stabilizes vitamin C and E.  

The structure is comprised of three areas that contribute to its free radical scavenging capabilities:

• The electron-donating group on the benzene ring: Gives the additional property of terminating free radical chain reactions.
• Carboxylic acid group: Provide additional attack sites for free radicals and thus prevent them from attacking the membrane.  
• Carboxylic acid group: Acts as an anchor, providing some protection against lipid peroxidation.

There are a few things to note about ferulic acid:

• More bioavailable than other dietary flavonoids and monophenolics.
• Has anti-inflammatory effects
• Has anti-diabetic effects
• Has anti-cancer effects
• Has anti-aging effects

And the list literally goes on…

Bottom line:  Ferulic acid exhibits a wide range of therapeutic properties: antioxidant, anti-inflammatory, anti-diabetic, and anti-aging effects.  It has been shown to stabilize solutions with vitamins C and E by doubling its photoprotection of skin.

Panthenol is the alcohol analogue of pantothenic acid, water-soluble vitamin B5; and often functions as a humectant, skin-conditioning agent, and hair conditioning agent.  Sources for pantothenic acid include jelly from queen bees, rice bran, molasses, and liver – with other sources from originating from meat, whole grains, legumes, eggs, milk, fruits, and vegetables.  

Varying studies found the following:

• A 2011 study evaluated the skin moisturizing efficacy of formulations containing different concentrations (0.5%, 1.0%, or 5.0% ) of panthenol.  Skin conditions in terms of moisture and transepidermal water loss (TEWL) were analyzed before and after 15 and 30 day periods of application.  The study determined that skin integrity was maintained by the improved protective effect of 1.0% panthenol added to the formulation.
• A 2014 study evaluated the safety, tolerability, and effectiveness of daily administration of an orally administered pantothenic acid-based dietary supplement in men and women with facial acne lesions.  The study found that 41 out of 43 subjects indicated that the administration of a pantothenic acid-based dietary supplement in healthy adults with facial acne lesions was safe, well-tolerated and reduced total facial lesion count versus placebo after 12 weeks of administration.
• A 2017 study evaluated skin moisturization, barrier restoration potential, and skin microflora of a topical panthenol-containing emollient.  The two-part study involved: 1) 23 subjects looking at TEWL, skin hydration, and intercellular lipid lamellae (ICLL) organization and 2) 20 subjects looking at quantitative bacterial cultures obtained over 6 h.  The study found lasting effects on barrier function and repair as well as skin hydration without negatively influencing bacterial viability.

In addition, the CIR panel assessed panthenol as safe with a concentration use of no more than 5% in non-coloring hair products, 0.6% in hair-coloring products, and 5% in rinse-off products.

Bottom line:   Panthenol/pantothenic acid (vitamin B5) functions as a humectant and skin-conditioning agent.  Shown to have effects on barrier function and repair, skin hydration, reduced TEWL, and bacterial viability.

Ah, hyaluronic acid (HA) or hyaluronan is the key molecule involved in skin moisture.  In this case, sodium hyaluronate which is the sodium salt of hyaluronan.  Hyaluronic acid is naturally found in our biological makeup. More specifically, skin HA accounts for most of 50% of total body HA. That’s a lot! And so, it is a key molecule in the fight against aging. And in the last five years (or longer) has exploded in its use and marketing capacity.

Hyaluronic acid is a glycosaminoglycan (GAG) with a unique capacity to bind and retain water molecules.  Indeed, various studies suggest HA homeostasis exhibits a distinct profile in intrinsic (internal) skin aging, which is totally different from that in extrinsic (external) skin aging.

It’s important to note that a lot of cosmetic and beauty brands often state that hyaluronic acid is able to hold 1000 times its weight in water.  And while I scanned all avenues of scientific publications for this very information, I found nothing that credibly links this exact number to a particular study or research-based calculation.

In fact, what I did find in my scientific hunt, was that researchers have determined that approximately one (1) gram of hyaluronic acid can hold up to six (6) liters of water. 

Does size matter with hyaluronic acid?

HA exists as a high molecular weight (HMW) molecule (or HMW HA) with a large molecular volume and low molecular weight (LMW) molecule (or LMW HA) with a low molecular volume.

The average molecular weight of the HMW HA molecule is 1000–8000 kilodaltons (kDa).  As the molecule increases in polysaccharide chain length, so does the volume and its overall weight. So when we look at the low end of the size range, LMW HA is fragmented (or broken down) hyaluronic acid and is often identified as sodium hyaluronate (or the sodium salt of hyaluronic acid).  Of course, there are variations in names and descriptors from suppliers/vendors based on hyaluronic acid size.  So keep that in mind.

Either way, if a product is formulated with hyaluronic acid, and you are looking for a power-packed hydrating ingredient – it’s generally a good thing that this guy is on the label.  There are a myriad of studies that tout its skin-improving benefits:

• Topical application of HA has been seen in reducing wrinkles.
• A 2014 study, using nano (really, really, really small) hyaluronic acid demonstrated a significant benefit in decreasing the depth of wrinkles (up to 40%), and skin hydration (up to 96%) and skin firmness and elasticity were significantly enhanced (up to 55%) at the end of eight weeks.

Sold! You don’t have to tell me twice that this is an amazing ingredient to add to my skincare arsenal. There is definitely a positive synergy that occurs when incorporating HA. But, as with any ingredient, concentration levels and actual % amount to the overall formulation is always critical.

Hyaluronic acid has been deemed safe by the CIR panel at concentrations up to 2% as a skin conditioning agent in cosmetics. 

Bottom line: Skin conditioning and humectant ingredient with studies demonstrating an increase in skin hydration, wrinkle reduction, and overall skin firmness.