What is Glycerin?
Glycerin, also called glycerol, is a natural organic compound present in all vegetable and animal oils and fats. In natural cosmetics, it is obtained as a byproduct of saponification, the soap-making process: when a vegetable oil reacts with a base, soap and glycerin are formed. In manyquality handmade soapsthe natural glycerin from the oil remains in the bar, which explains its smooth texture and moisturizing effect.
It can also be obtained by fermentation of vegetable sugars or by industrial synthesis. In natural cosmetics, only glycerin of plant origin is always used.
How it works on skin and hair
Glycerin is a humectant: it attracts water molecules from the environment and from the deeper layers of the skin to the surface, maintaining hydration in the skin and hair. It is one of the components of NMF (natural moisturizing factor), the system that the skin itself uses to regulate itself. Applying glycerin is, in a way, reinforcing what the skin already does on its own.
Unlike occlusive ingredients like petroleum jelly, it does not form a physical barrier but actively works by attracting water. That is why it works well in combination with emollients that seal this hydration once captured.
Properties and benefits
- Powerful humectant, attracts and retains water on the skin surface
- NMF component, strengthens the skin's natural hydration system
- Softening and gentle emollient, improves surface texture
- Soothing, reduces feelings of tightness and irritation
- Compatible with all skin types, including sensitive and reactive
- Non-comedogenic, does not clog pores
- Formula stabilizer, improves product texture and application
Use and integration into routine
Glycerin appears in many of our cosmetic products: handmade soaps, solid shampoos, shower gels. In natural saponification soaps, it is not an added ingredient but a result of the process: the glycerin you see in the INCI is the one that was born with the soap.
It combines especially well withhyaluronic acid, both humectants that enhance each other, withaloe verato add a soothing effect, and with vegetable oils such asjojobaorarganthat seal the hydration that glycerin has captured.
Curiosities and facts
Byproduct worth more than the product
In industrial soap manufacturing, glycerin was separated from the soap and sold separately, often to the pharmaceutical or food industry. In traditional artisan soap making, it was left in the bar, which resulted in softer and more nourishing soaps. Today, it is one of the selling points of artisan soaps compared to industrial ones: the natural glycerin is still there, without being extracted.
It's in nitroglycerin, but don't be scared
Nitroglycerin, the explosive, is obtained by nitrating glycerin. Same base molecule, completely different chemistry. Cosmetic glycerin has nothing to do with the explosive except the name; your soap won't explode in your hands. It is also in medicinal nitroglycerin, used to treat angina. A small molecule acting in a variety of contexts.
Naturally sweet
Glycerin has a slightly sweet taste, hence its name, which derives from the Greek "glykys," sweet. It is not sugar nor does it act as such in the body, but the palate detects it as sweet. Inoral hygiene productsit appears as a softening and moisturizing agent, and its neutral-sweet taste contributes to the palatability of the product.
This is how it appears in the INCI: Glycerin
Other active ingredients that may interest you
Hyaluronic acid: complementary humectant; together they form one of the most effective combinations for deep and long-lasting hydration.
Aloe vera: natural humectant and soothing agent, enhances the softening effect of glycerin on sensitive or reactive skin.
Propanediol: new generation plant-based humectant, frequently used with glycerin in modern formulas.
Jojoba oil: emollient that seals the hydration captured by glycerin, a classic and effective combination.