E422 – Glycerol - Food additives database

Safety grading GREEN – SAFE

Glycerol (E422), also known as glycerin or glycerine, is classified as GREEN because it is considered safe for human consumption by both the European Food Safety Authority (EFSA) and the U.S. Food and Drug Administration (FDA). It has been widely used for decades as a sweetener, humectant, and solvent in food, pharmaceutical, and cosmetic applications.

Glycerol is naturally present in fats and oils and is also produced commercially. It has a long record of safe use. Toxicological studies demonstrate that glycerol is not carcinogenic, mutagenic, or teratogenic. The body metabolizes glycerol easily, converting it to glucose or fat depending on energy needs. At normal levels in foods, it does not present safety risks.

Excessive consumption of glycerol may lead to mild side effects such as headache, thirst, nausea, or gastrointestinal upset. This is due to its osmotic effect, drawing water into the intestines. However, such symptoms are generally associated with very high doses, well beyond what would be ingested through normal dietary exposure. For this reason, glycerol is graded GREEN — SAFE.

Should You Avoid Glycerol?

Most people do not need to avoid glycerol. It is considered harmless in the small amounts present in food products. Individuals with rare metabolic disorders may require medical supervision, but this is uncommon. For the average consumer, glycerol is safe, and it can even play beneficial roles, such as improving the texture of low-fat foods and retaining moisture in baked products.

Common Uses

Sweetener and humectant in sugar-free foods, chewing gums, and candies
Moisture retention in baked goods
Thickener and stabilizer in beverages and liqueurs
Solvent for food colors and flavors
Used in pharmaceutical syrups and cough medicines
Cosmetic and personal care products (lotions, toothpaste, mouthwash)

Common Names / Synonyms

Glycerin
Glycerine
Propane-1,2,3-triol

What is it?

Glycerol is a simple polyol compound, chemically known as propane-1,2,3-triol. It is a colorless, odorless, viscous liquid with a sweet taste. Its unique chemical structure allows it to attract and retain water, which explains its humectant properties.

Commercially, glycerol is produced either by hydrolysis of natural fats and oils (such as vegetable oils) or as a byproduct of biodiesel production. In both cases, the glycerol is purified to food or pharmaceutical grade quality. This makes it a sustainable and widely available additive.

From a scientific perspective, glycerol is highly versatile. In foods, it functions not only as a sweetener but also as a stabilizer and solvent. Its ability to lower water activity helps extend the shelf life of products by reducing microbial growth. It is also metabolized by the body as a source of calories, providing about 4.3 kcal/g.

Glycerol’s safety has been confirmed by multiple studies. It is rapidly absorbed and utilized in the body’s natural metabolic pathways, converted to glucose or triglycerides as needed. This metabolic compatibility explains why it has such a long record of safe use across various industries.

Where it’s allowed (EU vs US)

Glycerol (E422) is approved for use as a food additive in both the European Union and the United States. The EU lists it in its official database of food additives, while the FDA recognizes it as GRAS (Generally Recognized as Safe). It is also approved in many other countries worldwide.

During the 2022 EFSA re-evaluation, experts confirmed that glycerol (E 422) is safe when produced from vegetable oils and fats and properly purified. Earlier manufacturing routes, such as chemical synthesis or microbial fermentation, could theoretically introduce impurities of toxicological concern (e.g., chlorinated or aldehydic by-products). The current European manufacturing standard requires that food-grade glycerol be obtained exclusively from vegetable sources and undergo distillation and clean-up steps to achieve high purity. EFSA therefore recommended updating EU specifications to reflect this practice, ensuring continued safety and product quality.

E422 – Glycerol