Glycerin: One of nature's miracles or something else?

January 4, 2019 Valerie Jaquith

What is Glycerin?

Glycerin (aka Glycerol) is a naturally occurring fatty alcohol (not drying alcohol) found in the cells of every animal and plant on Earth.

Glycerin plays a starring role in the life process itself - biosynthesis.
Glycerin is intrinsic to all life on Earth.
Without glycerin, life would not exist.

I have never had a concern about glycerine's safety, so I was very surprised when I was asked if it is potentially a dangerous, toxic disease agent!

The question I was asked is: could the purified form used in skin care be toxic and possibly lead to fatty liver disease if too much is absorbed - through our skin?!

We should take this very seriously!

The Bottom Line … despite decades of research into the safety and efficacy of glycerine in our skincare and cosmetics, there is no evidence to support claims that glycerin can lead to any kind of disease or that glycerin is in any way toxic in skin care.

Are there any concerns at all with glycerin applied to our skin?

Safe use of anything includes dose, source, and your own chemistry. Read on …

#1 GLYCERIN CAN BE AN ALLERGEN … for a few people. Allergy to topically applied glycerin does occur but is considered very rare. I did find enough anecdotal evidence to suggest that those with reactive, sensitive skin should always be testing every new product with a patch test (I tell you how to do that here) and/or consult an allergist for testing.

#2 IRRITATING OR DEHYDRATING? 100% pure, undiluted glycerin applied directly to the skin can cause localized skin dehydration in certain climates and temporary skin blistering in test subjects with normal skin. Sound familiar? Many naturally occurring compounds that are harmless or beneficial in proper amounts can cause a negative reaction depending on how it is used and how much of it is.

#3 CRICKETS … that’s it. There’s simply NO THERE THERE!

Let’s take a closer look into the question I was asked:

Is there any scientific evidence or medical research to support an allegation that glycerin is absorbed into the bloodstream, where it might be involved in liver disease?

The evidence clearly shows that the answer is NO! Not one shred. Nothing. Zilch. Let’s dive deeper …

Despite being one of the most widely studied skincare and cosmetic ingredients found in more than 15,000 products (it’s the third most common ingredient in cosmetics), the advisory panel unearthed nothing warranting further research.

…

The panel states: “Data on dermal absorption, distribution, metabolism, and excretion of glycerin were not found in the published literature, nor were unpublished data provided.”

…

This detailed Safety Assessment of Glycerin as Used in Cosmetics was published in 2015 by the Personal Care Product Council. This panel is a watchdog group that looks at the scientific literature and unpublished data relevant to assessing the safety of cosmetic ingredients and makes recommendations based on their findings. From the assessment:

The data clearly show low skin toxicity for multiple animal species and humans in both short—and long-term studies.
There were no reproductive or developmental effects observed in oral studies using animals.
Glycerin was not genotoxic in multiple in-vitro tests.
Glycerin is not carcinogenic to rats in a very long-term feeding study.
Glycerine is not a skin irritant and is non-sensitizing to guinea pigs and humans.
The Panel noted the high frequency of use reported for glycerin (over 15,000 cosmetic uses) and the low instances of reports of toxicity, irritation, and sensitization in the literature. It also noted that glycerin is GRAS for food packaging and as a multiple-purpose food substance. This information helped to further reduce the Panel’s concern about the use of this cosmetic ingredient.

I sure hope you can rest easier now that you’ve seen the evidence, we have more important things to worry about … not only is glycerin one of the safest ingredients we can include in our skincare …

Glycerin is one of NATURE’S miracles … in well-formulated SKIN CARE, it NOT ONLY SOOTHES IRRITATION AND RELIEVES DRY SKIN …

* it can actually heal our skin *

Glycerin (aka Glycerol, or glycerine) is a glycol molecule, an organic compound found everywhere and abundantly in nature in the form of triglycerides in all living cells.

A fat or oil from any animal or plant is composed of a glycol molecule (fatty alcohol) and three attached oil (lipid) molecules. Processing the oil/fat by exposing it to hydrogen (hydrolysis) releases the oils (lipid molecules) and the water-soluble glycerin in a chemical reaction called “saponification”. The glycerin can be removed and purified, this is how the glycerin we use in skin care is made. Glycerin is also created during the fermentation of sugars, occurring naturally in wine, beer, and bread. It can be synthetically manufactured from petroleum oils for commercial applications and is referred to as glycerol. Glycerin produced from any animal fat during saponification is chemically identical to glycerin derived from any oil, even a petro-oil.

In its purified form, glycerin is a sweet, syrupy water-soluble liquid that dissolves completely in water. It was discovered somewhat by accident by a Swedish chemist in 1779. Its vast potential for use in diverse industries and its benefit to skin were discovered later.

Today, glycerin is commonly purified from coconut and soy.

Organic standards matter: even if all pure glycerin, regardless of what it is made from, is chemically identical - I choose Organic and non-GMO kosher grade coconut-based glycerin to formulate with.

Glycerin is a “byproduct” of the hydrolysis of fatty acids. So, crafters of natural oil soap are making glycerin all the time when making soap. It’s created during the saponification process.

You might be surprised to learn that it’s the glycerin in well-crafted, natural oil soaps that is, in large part, responsible for why they give noticeable, long-term skin benefits. Most commercial “syn-dets” do not. Syn-dets are synthetic detergents that often look and function like SOAP - but they are not soap.

Glycerin is an “Alcohol”, or more correctly, a Fatty Alcohol.

Very briefly, I will touch on this subject: Distinguishing FATTY alcohols, all of which benefit skin, from DRYING alcohols is vital to choosing skin care that will not damage our skin over time.

FATTY ALCOHOLS …

All fatty alcohols play an important role in preserving and restoring healthy skin function. They are entirely non-irritating and improve skin function over time.

Fatty alcohols and drying alcohols are very different, so different in fact that drying, skin-damaging alcohols are about as related to fatty alcohols like glycerine as a shot glass full of whiskey is to a shot glass of pure olive oil.

Skin-loving, naturally derived fatty alcohols in skincare include:

Glycol (aks glycerol, glycerine, glycerin

Cetyl alcohol

Cetearyl Alcohol

Stearyl alcohol

Oleyl alcohol

Lauryl Alcohol

Myristyl Alcohol

DRYING ALCOHOLS (aka simple ALCOHOLS) ARE powerful EVAPORATIVE SOLVENTS …

Ethanol and Methanol

Isopropyl Alcohol (isopropanol, rubbing alcohol)

Isopropanol Alcohol

Denatured Alcohol

Benzyl Alcohol

SD alcohol 40

Rectified spirit (grain alcohol or neutral spirit)

**These alcohols are extremely drying to our skin yet are SO COMMON in skincare. All of these are well studied and known to cause “systemic eczematous contact dermatitis” and chemical sensitivities. Prolonged use of products containing drying alcohols can, and will, damage your skin over time, making it difficult to pinpoint the root cause of problems. Alcohol dermatitis: allergic contact dermatitis and contact urticaria syndrome

Buyer Beware: Some alcohols, specifically Everclear grain alcohol, are commonly found in products sold at apothecaries. Yes, this is a totally “natural” ingredient, and at high levels, it can preserve products against microbial growth, but in the pursuit of happy, resilient skin, I suggest avoiding these.

Back to glycerin in our skincare …

A little understanding of how glycerin functions and how it supports conditions associated with dry skin is important when looking to relieve these conditions (and debunking myths).

Maintains Water Balance (homeostasis): Glycerin in the body fills in the intercellular matrix between cells by attracting the right amount of water from the body to maintain the skin's homeostasis. It has been proven that glycerin is a powerful humectant in humid climates, forming a reservoir in the stratum corneum that lasts a long time, reducing the evaporation of moisture from the skin’s surface.

In low humidity conditions, rather than performing as a humectant, glycerin maintains the fluidity of the lipid membrane, a thin membrane made of two layers of lipid molecules in the stacked lipid bilayers, this is the glue that holds the corneocytes, dead skin cells, together and traps water. So when humidity is low, glycerin in this interior layer of the skin helps skin lipids do their jobs better. When the mercury plummets, Glycerin, being a glycol, has properties that make skin lipids more flexible and moisture at the skin surface from freezing. This same property makes glycol in other applications very valuable also - it is not “antifreeze” per se but it does reduce the temperature at which water freezes. I live in a super cold place, and I love to ski! I am often out all day in the cold - My skin stays noticeably more flexible and doesn’t freeze solid when I use glycerin-rich skin care.

Promotes Skin Cell Maturation: Researchers found that glycerin applied to the skin signals cells to mature in a normal manner. Glycerin may help skin disease, study finds | EurekAlert! Psoriasis is a skin condition where the skin cells don't mature properly, they shed before they are mature, leading to thick, scaly skin. This research showed that topical glycerin helps those with psoriasis by stimulating the skin cells to fully mature before shedding.

Improves the Appearance of Skin: In addition to keeping moisture levels high, glycerin is a natural emollient with mild exfoliating properties, helping maintain softness and suppleness. When skin is plump and hydrated, it looks, feels, and functions better. It does this by locking lipids within the stratum corneum, and the effects of just one application are long-lived.

Removes dead cells: Our skin cells are held together by proteins. These proteins can clump dead cells together, preventing new ones from forming. Glycerin has mild cleansing properties that assist the breakdown of proteins and lubricating properties that help slough off dead cells.

… the best news: Healing properties & barrier repair

Not only is glycerin extremely moisturizing, but new research indicates that glycerin has a repairing action on the barrier function showing it doesn’t just relieve dry skin conditions, it can HEAL them. The following articles present the evidence in great detail: Barrier Function: Your Skin's Security Guard | The Naked Chemist Educated Therapists

Topically, glycerin promotes the synthesis of lipids in the epidermis, guiding cells to grow and mature properly, accelerating wound healing, and reducing bruising. Glycerin has also been shown to help treat fungal infections in disorders like eczema and psoriasis.

Rosacea RELIEF?

Topical 90% medical grade Kanuka honey and 10% glycerin is shown to be a safe, natural, and effective rosacea treatment, according to a study published June 24, 2015, Randomised controlled trial of topical kanuka honey for the treatment of rosacea | BMJ Open.

Kanuka honey is collected from a variety of tea tree species in New Zealand closely related to the Manuka species.

The bottom line is that glycerin heals and supports healthy, resilient skin.

❤ It really IS one of nature's wonders ❤

“Biosynthesis” is the life process itself - the complex, multi-step, enzyme-catalyzed biological process where a substrate (a substance on which an enzyme acts) is converted into a more complex compound where it performs numerous roles supporting all life. Glycerin plays an important role in this process in every plant and animal. Until I uncover peer-reviewed evidence to support claims to the contrary, I’ll continue singing the praises of glycerin (and glycerites) in skincare. So unless you’re one of the unlucky few allergic to this miraculous compound - I not only recommend it highly as a beneficial ingredient that may assist in the healing of an impaired skin barrier, I include infused glycerites in many of my skincare creations.

I’m more inspired than ever to make my glycerites. A glycerite is pure glycerin infused with medicinal herbs which can then be incorporated into skin care.

RELEVANT PEER REVIEW RESEARCH:

Safety Assessment of Glycerin as Used in Cosmetics