Get Your Personalized Supplement StackSupplement Stack Quiz

Glyceryl Stearate

Also known as: Glyceryl Stearate, glycerol monostearate, E471

Overview

Glyceryl stearate is a fatty acid ester formed from glycerol and stearic acid, a saturated long-chain fatty acid found naturally in both animal and plant fats. It is primarily utilized as an emulsifying agent, lubricant, and stabilizer in a wide range of products, including cosmetics, pharmaceuticals, and food. In cosmetic and topical formulations, it is valued for its ability to improve texture, enhance stability, and provide emollient properties, acting as a skin-conditioning agent. While widely recognized as non-toxic and biodegradable, research on glyceryl stearate has predominantly focused on its safety and functional applications in these industries. Direct clinical research on its systemic health effects or benefits as a dietary supplement ingredient is very limited, and there is currently no high-quality evidence to support its use for therapeutic purposes when taken orally.

Benefits

Glyceryl stearate's primary benefit is its role as a topical emollient and emulsifier in cosmetic and pharmaceutical formulations. When applied topically, it helps to improve skin barrier function and hydration, contributing to smoother and softer skin. There is no direct, high-quality clinical evidence from randomized controlled trials or meta-analyses to support any systemic health benefits of glyceryl stearate when consumed as a supplement. While some in vitro studies suggest that free stearic acid (a component of glyceryl stearate) can induce apoptosis in cancer cells, these findings are concentration-dependent, relate to the free fatty acid rather than the ester, and their clinical relevance to human health or cancer treatment is currently unclear and unproven. Therefore, no specific clinical benefits have been identified for human populations from glyceryl stearate supplementation.

How it works

As an emulsifier, glyceryl stearate primarily functions by stabilizing oil-in-water or water-in-oil mixtures, preventing separation of ingredients in formulations like creams and lotions. When applied topically, it forms a protective barrier on the skin surface, which helps to reduce transepidermal water loss, thereby improving skin hydration and acting as an emollient. Systemic absorption of glyceryl stearate from topical application is minimal. If ingested, it would likely be metabolized into glycerol and stearic acid, which are common dietary components. While stearic acid can influence cell membrane composition and has been studied for its potential role in apoptosis pathways in vitro, glyceryl stearate itself does not have specific molecular targets identified for therapeutic action.

Side effects

Glyceryl stearate is generally recognized as safe (GRAS) for both topical and oral use at typical concentrations. Acute and repeated dose studies have shown no significant toxicity. Common side effects are rare but can include mild skin irritation or allergic reactions in individuals with sensitivities, particularly when used in topical products. There are no well-documented uncommon or rare side effects at typical exposure levels. Some animal studies, particularly those involving very high dietary doses (e.g., up to 25% of the diet), have reported findings such as tumor development; however, these findings are inconsistent, have not been confirmed in humans, and their relevance to typical human exposure is limited. No significant drug interactions have been reported for glyceryl stearate. There are no established contraindications for its use. While specific studies on its safety during pregnancy and lactation are limited, it is generally presumed safe due to its low systemic exposure and GRAS status.

Dosage

There is no established minimum effective dose or optimal dosage range for glyceryl stearate as a dietary supplement, as it is not typically used for therapeutic supplementation. Its primary applications are as an ingredient in topical formulations and as a food additive. In topical creams and lotions, it is commonly used at concentrations ranging from 1% to 10%. For oral consumption, it is used as a food additive (E471) in various products, but not as a standalone supplement. Animal studies have explored very high dietary doses (e.g., up to 25% of the diet) without acute toxicity, but these findings have limited relevance to human safety thresholds for supplementation. Due to its primary use in topical applications, timing considerations for oral intake are not applicable. Systemic absorption from topical use is limited.

FAQs

Is glyceryl stearate safe for skin use?

Yes, glyceryl stearate is widely used in cosmetics and topical products and has a good safety profile. It is generally recognized as safe for skin application.

Does glyceryl stearate have health benefits when taken orally?

There is no evidence from high-quality clinical trials to support any health benefits from oral supplementation with glyceryl stearate. Its primary role is as an emulsifier and stabilizer in food.

Can glyceryl stearate cause cancer?

Some animal studies at very high doses showed tumor development, but these findings are inconsistent and have not been observed in humans. It is not considered a human carcinogen at typical exposure levels.

Is glyceryl stearate the same as stearic acid?

No, glyceryl stearate is an ester of stearic acid and glycerol. Stearic acid is a free fatty acid. While related, their chemical structures and biological effects can differ.

Research Sources

https://cir-reports.cir-safety.org/view-attachment?id=6cf0cc9e-8d74-ec11-8943-0022482f06a6 – This is a safety assessment by the Cosmetic Ingredient Review (CIR) Expert Panel. It reviews toxicology studies on glyceryl stearate, concluding that it is non-toxic at typical use levels in cosmetics. The report notes some tumor findings in mice at very high doses, but overall supports its safety for cosmetic use, though it lacks clinical efficacy data for therapeutic purposes.
https://cir-reports.cir-safety.org/view-attachment?id=6befb9a7-8e74-ec11-8943-0022482f06a6 – This CIR report provides further detailed safety data and toxicological information on glyceryl stearate. It supports the conclusion that glyceryl stearate is safe for use in cosmetic products at current concentrations, based on a comprehensive review of available animal and in vitro studies, despite some limitations in translating animal data directly to humans.
https://pmc.ncbi.nlm.nih.gov/articles/PMC2946230/ – This in vitro study investigated the effects of stearate (a free fatty acid, not glyceryl stearate directly) on human breast cancer cell lines. It found that stearate induced apoptosis preferentially in cancer cells at physiological concentrations. While providing mechanistic insight, this study's findings are limited to in vitro conditions and do not directly translate to clinical efficacy or safety of glyceryl stearate in humans.