Highlights 

• Glycerin is a type of carbohydrate called a sugar alcohol, or polyol. 
• Glycerin contains slightly more calories per gram than sugar and is 60–75% as sweet. 
• Glycerin occurs naturally in fermented foods and beverages, including beer, honey, vinegar, wine and wine vinegar. It is also commercially produced from fats and oils or through the fermentation of yeast, sugar or starch.
• Glycerin is used in a variety of food and drink products, including various beverages, nutrition and energy bars, cake icings, soft candies, chewing gum, condiments, creams, diet foods, dried fruits, fondant, fudge and marshmallows.
• Glycerin’s safety has been confirmed by multiple global health authorities, including the U.S. Food and Drug Administration. 

The basics of glycerin

Glycerin (pronounced GLIH–sir–in) is classified as a type of carbohydrate called a sugar alcohol, or polyol. Glycerin is another name for glycerol, the three-carbon backbone of a triglyceride. It is formed naturally through the alcoholic fermentation of sugars; however, most of the glycerin we consume is produced from the hydrolysis of fats and oils, and in lesser quantities through the fermentation of yeast, sugar or starch. Glycerin is used as an ingredient in a variety of food and beverage products to help retain moisture, prevent sugar crystallization, and add bulk, smoothness, softness, sweetness and texture.

Like most sugar alcohols, glycerin is not as sweet as sugar—it is about 60–75% as sweet. Glycerin is more calorie-dense than other sugar alcohols and contains more calories per gram (4.32) than sugar (3.87). 

Glycerin’s safety has been reviewed and confirmed for use in food by health authorities around the world, including the World Health Organization, the European Union, and countries such as Australia, Canada and Japan. The U.S. Food and Drug Administration (FDA) has also declared glycerin safe for consumption.

While the safety of glycerin (and other sugar alcohols) is well documented, when eaten in excessive amounts, some sugar alcohols (e.g., mannitol and sorbitol) can cause gastrointestinal discomfort, including gas, bloating and diarrhea. As a result, packaged foods that contain mannitol or sorbitol must include a warning on their label about potential laxative effects. Because glycerin has been shown to be well-tolerated at current consumption levels, products that contain glycerin do not require a warning label.

Glycerin consumption

When we consume glycerin, it is readily and completely absorbed in the small intestine. Like other sugar alcohols (with the exception of erythritol), glycerin contains calories in the form of carbohydrate. Yet despite its being a carbohydrate source, glycerin does not significantly promote insulin secretion when it’s consumed which helps keep the body’s blood glucose levels lower than the levels produced by eating other types of carbohydrate, including sugars. 

Recommended intake

Glycerin is not an essential part of a balanced diet, but consuming it (even in high amounts) has not been shown to be detrimental to human health. Therefore, no acceptable daily intake level has been established.

Consuming large doses of glycerin at one time may produce mild laxative effects, headache, thirst, nausea or hyperglycemia, but such quantities are not found in individual foods or a typical diet.

Unlike other polyols, glycerin is not considered necessary to exclude as part of a low Fermentable Oligosaccharides Disaccharides Monosaccharides And Polyols (FODMAP) diet because it is completely absorbed in the small intestine and does not reach the large intestine.

Food sources of glycerin

Because of its versatile attributes as a moisture retainer, preservative, sweetener and thickener, glycerin is used in a wide variety of foods and beverages, including nutrition and energy bars, various drinks, cake icings, soft candies, chewing gum, condiments, diet foods, dried fruits and vegetables, marshmallows, soups, spices and seasonings. Glycerin is also naturally found in fermented foods and beverages such as beer, honey, vinegar, wine and wine vinegar.

Interested in learning the basics of other food, nutrition and health topics? Check out our “What Is” series.