Hydration up after 10 days at 20%
Clinical trialCorneometry values, a sign of hydration, increase significantly. Skin water loss and sensitivity to an irritating surfactant (SLS) do not change7.
Vegetable glycerin (glycerol) in cosmetics
Glycerin, or glycerol, is the reference humectant: it attracts water into the stratum corneum, where skin naturally contains it5. A 20% cream increases measured hydration after 10 days7. Its origin, plant, animal or synthetic, does not appear in the INCI name: it is a specification requirement.
Glycerin at a glance
Entry from our cosmetic ingredient glossary. Regulatory data from the European Commission's CosIng database1 and Regulation (EC) 1223/20092, safety according to the CIR expert panel3. Copy the identifiers in one click for your files.
- INCI name
- GLYCERIN
- Other names
- GlycerolGlycerol (INN), propane-1,2,3-triol, glycerolum (European Pharmacopoeia)1
- CAS number
- 56-81-5
- EC number
- 200-289-5
- Formula
- C₃H₈O₃Molar mass 92.09 g/mol
- CosIng functions
- Humectant, skin and hair conditioner, solvent"Humectant", "skin conditioning - humectant", "hair conditioning", "skin protecting", "solvent" and "viscosity controlling", among others1
- Appearance
- Colorless, viscous, odorless liquidMiscible with water in all proportions
- Origin
- Plant, animal or syntheticThe INCI name does not distinguish the origin, and the molecule is identical in all cases. Require it from the supplier through a certificate of origin
- EU status
- No restrictionAbsent as a substance from annexes II to VI of Regulation (EC) 1223/2009 as consolidated on May 1, 20252
- Allergen to declare
- NoAbsent from the fragrance allergen list of Regulation (EU) 2023/1545
- Safety
- Judged safe in cosmeticsCIR panel 2019: safe in the practices of use and concentrations described3
What the research says
Each result shows the protocol and the level of evidence. The higher the level, the better the result carries over to a finished formula.
Clinical trialReview or consensusLaboratory
Skin and hydrationSkincare
Glycerol hydrates, petrolatum limits water loss
Clinical trialThe complete cream reduces water loss compared with the vehicle and increases hydration compared with the vehicle alone and with the vehicle containing petrolatum. The authors attribute the drop in water loss to petrolatum and the hydration to glycerol9.
Stratum corneum glycerol is linked to its hydration
Clinical trialStratum corneum hydration follows its glycerol content, more closely than sebum production. After immersion in water, both drop together, then glycerol returns to normal within a few hours. This finding supports glycerin-based moisturizers5.
Without aquaporin-3, less glycerol and less hydrated skin
LaboratoryStratum corneum water drops by about 50% and its glycerol falls from 5.5 to 2.3 nmol per µg of protein; elasticity and barrier recovery decrease. An animal result: it explains the role of glycerol without proving the effect of an applied product6.
BodyBodycare
Niacinamide and glycerin lotions: dryness and water loss
Clinical trialCompared with six other body lotions, the two formulas gave the largest improvement in visible dryness, hydration and skin water loss. The share of glycerin is not isolated from that of niacinamide13.
Origin and properties of the materialFormulation
A biodiesel by-product
LaboratoryEvery ton of biodiesel produced generates about 100 kg of glycerol. Crude, it contains methanol, oil, soap and salts; a two-step purification reaches 98.2%11. Crude glycerol is a by-product coming mainly from this industry12.
Maximum water retention between 60 and 70% in solution
LaboratoryWater retention increases with concentration up to 60%. Between 60 and 70%, the solution does not change weight on evaporation; above 70%, it absorbs ambient moisture10.
Expert viewDermatology
Judged safe in cosmetics
Expert assessmentThe panel reviewed the animal and human data and concludes that glycerin is safe in the practices of use and concentrations described3.
Hydration, barrier and mechanical properties of the skin
ReviewThe review describes improved stratum corneum hydration, barrier function and mechanical properties of the skin, as well as protection against irritant stimuli. Endogenous glycerol passes through aquaporin-34.
Less stinging than a urea cream
Clinical trialModerate or severe stinging is reported by 10% of users of the glycerin cream, versus 24% with urea. The effect on dryness is judged equivalent. A population with atopic skin: transpose the result with caution8.
This page summarizes published literature on a cosmetic ingredient. It does not describe the effect of a finished product, which depends on its formula, and it is not medical advice. Some of the studies cited were run or funded by manufacturers; this is shown in the sources. Glycerin is a basic ingredient: studies often cover complete creams, where its share is not always isolated; the page says so each time.
Concentrations used in studies
The two clinical trials cited test a 20% glycerin cream78. Pure, it is not applied as is: in vitro, water retention peaks between 60 and 70%, then the solution absorbs moisture from the air10. The level in a finished product is set with the formulator, according to the texture and feel you want.
Which products use glycerin?
Our white label catalog includes 15 formulas with glycerin: the key active in 1 of them, a supporting ingredient in the others. Every category can be customized (formula, fragrance, packaging).
6Face
Supporting humectant in hydrosol-based toners, cleansing gels, scrubs and eye contour care.
8Body
Humectant in mists, liquid soaps, shower gels, body masks and sun care or aftershave products.
1Hair
Supporting humectant in heat-protectant hair sprays; CosIng recognizes a hair conditioning function.
In our formulas, it is most often paired with
Argan oil 8Aloe vera 6Panthenol 5Niacinamide 4Allantoin 3Glycerin, urea, panthenol or betaine?
Four humectants or moisturizers often combined. They complement each other more than they compete; each has its own detailed page.
| Glycerin | Urea | Panthenol | Betaine | |
|---|---|---|---|---|
| CosIng functions | Humectant, skin and hair conditioner, solvent1 | Humectant, see the urea page | Skin and hair care, antistatic | Humectant, hair conditioner |
| In the skin | Yes: stratum corneum glycerol, via aquaporin-356 | Component of the natural moisturizing factor, see the page | See the panthenol page | Osmolyte that skin can transport, see the page |
| Tolerance | Moderate or severe stinging in 10% of users of a 20% cream8 | 24% with a cream at 4% urea and 4% salt, in the same study8 | See the panthenol page | See the betaine page |
| EU regulation | No restriction12 | No restriction | No restriction | No restriction |
Frequently asked questions about glycerin
Vegetable glycerin: where does it come from?
Glycerin is the backbone of fats and oils: it is recovered by separating the fatty acids. "Vegetable" means it comes from plant oils; crude glycerol is today a by-product coming mainly from biodiesel production1112. A glycerin can also be of animal origin or come from chemical synthesis, and the INCI name GLYCERIN does not say which. For a brand, origin is a specification requirement: ask the supplier for a certificate of origin.
Vegetable glycerin vs glycerin: is there a difference?
Chemically, no: it is the same molecule, glycerol (CAS 56-81-5)1. The difference lies in the specification: a plant origin can be required for a natural or vegan positioning, and the purity grade (cosmetic or pharmacopoeia) is set at purchase.
What are the benefits of glycerin for skin?
What percentage of glycerin should you use?
Is glycerin safe?
The CIR panel judges it safe in the practices of use and concentrations described3 and it is not restricted in the EU2. In a trial on atopic skin, 10% of users of a 20% cream report moderate or severe stinging, versus 24% with a urea cream8. During pregnancy, as with any skincare product, a healthcare professional's advice remains the rule.
Is glycerin good for hair?
CosIng recognizes a hair conditioning function1. We kept no controlled hair study: this page therefore says no more.
Can you manufacture a glycerin moisturizer for my brand?
Yes. Our ISO 22716 certified lab offers 15 formulas containing glycerin (lotions, gels, soaps, mists, creams, hair sprays) to customize, or a custom formula. Free samples are included.
- Rose water: real benefits and how to recognize a true hydrosolWhy a hydrosol is completed by a humectant like glycerin
- Menopause skin: formulating a compliant skincare range in 2026Actives for dryness, glycerin included, and claims to avoid
- Peri-procedural skincare: creating your private label rangeAn example of an aloe vera and glycerin aqua-gel formula
- Cosmetic product specification: 5 secrets to get it rightWhere the origin requirement for raw materials is decided
Sources
Peer-reviewed studies and official regulatory sources, checked on November 3, 2026.
- European Commission. CosIng, entry GLYCERIN (CAS 56-81-5, EC 200-289-5). ec.europa.eu/growth/tools-databases/cosing
- European Parliament and Council. Regulation (EC) No 1223/2009 on cosmetic products, consolidated version of May 1, 2025: no entry for glycerin in annexes II to VI. eur-lex.europa.eu
- Becker LC, Bergfeld WF, Belsito DV, et al. Safety Assessment of Glycerin as Used in Cosmetics. Int J Toxicol. 2019;38(3 Suppl):6S-22S. doi:10.1177/1091581819883820
- Fluhr JW, Darlenski R, Surber C. Glycerol and the skin: holistic approach to its origin and functions. Br J Dermatol. 2008;159(1):23-34. doi:10.1111/j.1365-2133.2008.08643.x
- Choi EH, Man MQ, Wang F, et al. Is endogenous glycerol a determinant of stratum corneum hydration in humans?. J Invest Dermatol. 2005;125(2):288-293. doi:10.1111/j.0022-202X.2005.23799.x
- Hara M, Ma T, Verkman AS. Selectively reduced glycerol in skin of aquaporin-3-deficient mice may account for impaired skin hydration, elasticity, and barrier recovery. J Biol Chem. 2002;277(48):46616-46621. doi:10.1074/jbc.M209003200
- Lodén M, Wessman W. The influence of a cream containing 20% glycerin and its vehicle on skin barrier properties. Int J Cosmet Sci. 2001;23(2):115-119. doi:10.1046/j.1467-2494.2001.00060.xACO Hud
- Lodén M, Andersson AC, Anderson C, et al. A double-blind study comparing the effect of glycerin and urea on dry, eczematous skin in atopic patients. Acta Derm Venereol. 2002;82(1):45-47. doi:10.1080/000155502753600885ACO Hud
- Vaillant L, Georgescou G, Rivollier C, Delarue A. Combined effects of glycerol and petrolatum in an emollient cream: a randomized, double-blind, crossover study in healthy volunteers with dry skin. J Cosmet Dermatol. 2020;19(6):1399-1403. doi:10.1111/jocd.13163Pierre Fabre
- Chen HJ, Lee PY, Chen CY, et al. Moisture retention of glycerin solutions with various concentrations: a comparative study. Sci Rep. 2022;12(1):10232. doi:10.1038/s41598-022-13452-2Healthmate
- Abdul Raman AA, Tan HW, Buthiyappan A. Two-step purification of glycerol as a value added by product from the biodiesel production process. Front Chem. 2019;7:774. doi:10.3389/fchem.2019.00774
- Luo X, Ge X, Cui S, Li Y. Value-added processing of crude glycerol into chemicals and polymers. Bioresour Technol. 2016;215:144-154. doi:10.1016/j.biortech.2016.03.042
- Christman JC, Fix DK, Lucus SC, et al. Two randomized, controlled, comparative studies of the stratum corneum integrity benefits of two cosmetic niacinamide/glycerin body moisturizers vs. conventional body moisturizers. J Drugs Dermatol. 2012;11(1):22-29. PMID 22206073Procter & Gamble
Tell us about your project
A product specialist reviews your request and gets back to you on the channel you prefer.
No obligation. Your information stays confidential and is used only to prepare your quote.