A naturally occurring polyol that draws moisture from the air to keep skin hydrated and supple. The third most commonly used cosmetic ingredient worldwide — found in over 15,000 products — with an outstanding safety record spanning decades of research.
A powerful moisture-binding agent that draws water from the air and deeper skin layers to keep the surface hydrated and plump. It also helps improve product texture and feel while providing gentle skin conditioning benefits. This ingredient has an excellent safety profile and is well-tolerated by all skin types, including sensitive skin.
Glycerin (CAS No. 56-81-5) is a simple polyol compound with three hydroxyl groups and a molecular formula of C3H8O3. It is naturally occurring in all animals and plant matter as glycerides in fats and oils. For cosmetic use, natural glycerin is obtained as a byproduct in the conversion of fats and oils to fatty acids or fatty acid methyl esters (e.g., soap-making or biodiesel production). Synthetic glycerin can also be produced from propylene. It is completely miscible with water and has solvent properties similar to water and simple aliphatic alcohols, making it an incredibly versatile formulation ingredient.
According to 2014 FDA VCRP data, Glycerin is the third most frequently reported ingredient in the cosmetic database — after water and fragrance — appearing in 15,654 cosmetic products. It is used at concentrations up to 79.2% in leave-on products and 99.4% in rinse-off products (CIR, 2014). The FDA considers Glycerin GRAS (Generally Recognized As Safe) for food use, and it is also approved as an OTC drug for ear wax removal, skin protection, and oral care.
As a humectant, glycerin draws water from the environment and deeper dermis to the skin surface. Its three hydroxyl groups form hydrogen bonds with water molecules, providing lasting hydration without a heavy feel.
By maintaining optimal moisture levels, glycerin reduces roughness and flakiness. It improves the appearance of fine lines caused by dehydration, giving skin a visibly smoother, more even texture.
Glycerin strengthens the skin's natural moisture barrier, reducing trans-epidermal water loss (TEWL). A well-hydrated barrier is more resilient against environmental stressors and irritants.
Well-tolerated by all skin types. The CIR report confirmed no irritation at 50% concentration in subjects with dermatitis (n=420). Also acts as a viscosity modifier, improving product feel and spreadability.
Suitable for: All skin types — dry, oily, combination, sensitive, and acne-prone.
The CIR Expert Panel (December 2014) concluded that glycerin is safe as a cosmetic ingredient in the practices of use and concentration described in their safety assessment. EU approved with no restrictions. FDA GRAS for food use.
In very low-humidity environments, glycerin (like all humectants) may draw moisture from deeper skin layers rather than the air. Pair with an occlusive moisturizer (ceramides, squalane, or petrolatum) to lock in hydration.
At very high concentrations (above 30%), glycerin can feel sticky on the skin. Most effective consumer products use 2%–10% for optimal feel and efficacy.
The CIR Panel noted that glycerin derived from the Jatropha plant may contain phorbol esters. The FDA advises that glycerin from this source should not be used in cosmetics. Conventional impurity tests may not detect these toxins.
The CIR 2014 report reviewed multiple reproductive and developmental toxicity studies. Oral NOAEL for maternal toxicity and teratogenicity: 1,310 mg/kg/d in rats, 1,280 mg/kg/d in mice, and 1,180 mg/kg/d in rabbits — with no fetal abnormalities observed in any species. No adverse effects were seen in rats administered 20% glycerin in drinking water throughout gestation and nursing; the F1 generation reproduced normally. Topical glycerin is generally considered safe during pregnancy, but always consult your healthcare provider.
Start with a gentle cleanser. Many cleansers already contain glycerin — it helps maintain moisture during the cleansing process.
While your skin is still damp, apply your glycerin-containing product (serum, toner, or essence). Damp skin gives glycerin water to bind to immediately, maximizing its humectant effect.
Follow with a cream or oil-based moisturizer to create an occlusive layer. This prevents the water glycerin has attracted from evaporating — especially important in dry or cold climates.
Lightweight hydration for layering. Fast absorption. Great for oily and combination skin. CIR reports glycerin used at up to 79.2% in leave-on products.
Hydration + occlusion in one step. Better for dry skin and low-humidity environments. Glycerin at 5%–15% in moisturizers is the sweet spot.
Glycerin in rinse-off products (used at up to 99.4%) helps prevent the tight, dry feeling after washing. A staple in gentle and micellar cleansers.
Double humectant power: HA holds up to 1,000x its weight in water while glycerin provides steady, long-lasting moisture. A hydration superteam.
Niacinamide strengthens the skin barrier while glycerin supplies hydration. Complementary mechanisms with no conflict.
Occlusive ingredients that seal in the moisture glycerin attracts. The ideal partner to prevent water loss, especially in dry climates.
Glycerin counteracts the dryness and peeling retinol can cause. Apply retinol first, then follow with glycerin-based moisturizer as a buffer layer.
Without an occlusive seal, glycerin may draw moisture from deeper skin layers rather than the air when humidity is below 40%. Always follow with a cream.
Pure glycerin (above 30%) can feel sticky and may not absorb well. Dilute or choose products formulated at 2%–15% for best feel and efficacy.
Found in 34,603 product variants in our database. Here are some well-known options:
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