Ingredient | Amino Acid-Derived Antioxidant
Ergothioneine
INCI · Ergothioneine
Related names and forms: EGT. This list does not indicate synonyms or exact ingredient matches.
Ergothioneine (INCI: Ergothioneine; EGT) is an amino acid (histidine)-derived antioxidant found naturally in sources such as mushrooms and some bacteria. Its distinguishing feature is relative stability compared with many antioxidants, which is why it has become more common in cosmetic formulas in recent years. It is discussed within a cellular-network context associated with antioxidant transport and balance systems, including a specific transporter in the literature. As its popularity is relatively recent, the size of its effect needs a measured interpretation in cosmetics. It appears on labels as Ergothioneine and has a verified individual PubChem record (CID 5351619, C9H15N3O2S). Klaris assesses ergothioneine alongside concentration, companion antioxidants and a measured view of its effects.
i. Cosmetic Functions
Frequently Discussed Effects
The following headings summarise areas of effect frequently discussed in the literature; visible results in each area require regular use and a suitable formula.
Stable Antioxidant
An ingredient with a relatively resilient structure, studied in relation to oxidative stress appearance.
Cellular Network Context
Discussed as a compound associated with cellular antioxidant transport and balance systems.
Compatibility with Other Antioxidants
May be included in an antioxidant combination with ingredients such as vitamins C and E and niacinamide.
Mechanism
What Happens Within the Skin?
The following points summarise mechanisms from dermocosmetic literature in plain English. Klaris presents them as background information to help readers understand the context, not as medical claims.
Step 1
Amino Acid-Derived Antioxidant
A histidine-derived antioxidant from fungal or microbial sources, studied in relation to oxidative stress appearance.
Step 2
A Relatively Stable Structure
Its relative resilience compared with many antioxidants is a distinguishing feature that makes it convenient to formulate.
Step 3
Cellular Network Context
Discussed in the literature as a compound associated with cellular antioxidant transport and balance systems.
Step 4
Compatibility with Other Antioxidants
May be included in an antioxidant combination with ingredients such as vitamins C and E, niacinamide and glutathione.
Step 5
Recent Popularity and Measured Expectations
Its popularity is relatively recent. The size of its effect is considered with restraint in cosmetics, with some distance from promises.
ii. Role in the Formula
How Is It Read on a Label?
Ergothioneine is a relatively stable antioxidant used at low concentrations in water-based serums and creams. It is positioned alongside other antioxidants as part of an antioxidant-network approach. The size of its effect is considered with restraint in cosmetics.
A Closer Look · pH, Stability, Synergy
Ergothioneine is a fungal- or microbial-derived antioxidant used at low concentrations in water-based serums and creams. Its distinguishing feature within an antioxidant combination is relative stability. Unlike antioxidants highly sensitive to oxidation, such as vitamin C or resveratrol, ergothioneine is more resilient, which makes formulation easier. The literature discusses it within the cellular antioxidant network, associating it with systems that transport or accumulate antioxidants in cells. Klaris considers this an interesting layer of information, not an exaggerated promise of cell protection. Because its popularity is relatively recent and social media may attach strong promises to it, the size of its effect needs a measured interpretation in cosmetics. The antioxidant combination and whole formula are more decisive than dramatic standalone claims. It is often positioned with ingredients such as vitamins C and E, niacinamide and glutathione. When assessing an ergothioneine product, Klaris considers concentration, companion antioxidants and the whole formula with appropriate restraint.
Typical Concentration Range
Low concentrations (depending on the formulation context)
Ingredient Family
Antioxidants
iii. Sensitivity Advisory
A Note on Extra Care in Context
Generally described as having a low-irritation profile. A patch test is a measured approach for sensitive profiles.
A sensitivity advisory is not an instruction for use; where individual health circumstances, pregnancy or known sensitivities are involved, discussing the decision with your doctor may be a more contextual approach.
Common Misconceptions
Frequently Confused Points
Common Belief
Ergothioneine is a miraculous or the latest super antioxidant.
A More Contextual Reading
Ergothioneine is an interesting, relatively stable antioxidant, but carries no super or miracle promise. The size of its cosmetic effect is considered with restraint and within the whole formula.
Common Belief
Because it is stable, the formula needs no stability design.
A More Contextual Reading
Ergothioneine is relatively resilient, but this does not remove the stability requirements of the rest of the formula, including other actives and packaging. The whole still matters.
Common Belief
A natural mushroom antioxidant is automatically safe or suitable.
A More Contextual Reading
It is generally described as having a low-irritation profile, but natural does not automatically mean suitable. Individual sensitivity is possible, and the whole formula is decisive.
Common Belief
It is a sufficient antioxidant on its own.
A More Contextual Reading
It is generally used alongside other antioxidants. It is considered through the wider antioxidant combination and the whole formula, not alone.
Scientific Basis
Sources and Their Scope
The following headings indicate areas of research; they are not citations of a specific publication or confirmation that every statement on this page has been verified. The links provided should be read with their individual scope in mind.
- International INCI / CosIng database
- Dermocosmetic research publications
Source Links
- Database RecordPubChem | Ergothioneine Ingredient Record (CID 5351619)
Database records provide ingredient identity and registration information; on their own, they do not establish the effect of a finished product or its suitability for a profile. Search links are not specific research papers.
iv. Related Ingredients
Ingredients Often Read Together
v. Antioxidants Family
Other Ingredients in the Same Family
Explore ingredients in the same functional family to deepen your reading of formulas.
vi. Academy · Related Reading
For a Closer Look
Klaris · Example Analyses
How Does Ergothioneine Feature
in Your Products?
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