Ergothioneine
What is Ergothioneine?
Ergothioneine is a sulfur-containing derivative of the amino acid histidine, featuring a thione group that confers remarkable stability. Naturally synthesized by fungi and certain bacteria, it accumulates in high concentrations in mushrooms and is selectively taken up by human cells via the OCTN1 transporter. This underscores its physiological significance across species. In cosmetics, it belongs to the antioxidant category, where it neutralizes reactive oxygen species like singlet oxygen and peroxynitrite, while chelating transition metals that promote oxidation. By intercepting free radicals and inhibiting lipid peroxidation, ergothioneine safeguards polyunsaturated oils, volatile fragrances, and labile actives from degradation. This preserves color, scent, and efficacy throughout shelf life. Applied to skin, it integrates into cellular compartments to reinforce endogenous defenses against everyday oxidative challenges from pollution and light exposure.
Roles in Formulation
This ingredient serves the following purposes in cosmetic formulations:
Benefits
Prevents oxidation in formulas to maintain product freshness and stability.
Bolsters skin's natural antioxidant network against environmental stressors.
Non-comedogenic, making it suitable for pore-conscious routines.
Who It's For
A quick guide for who this ingredient may suit (and who should be cautious).
| Who May Benefit | Who Should Avoid |
|---|---|
| People in high-pollution environments seeking extra oxidative support. | Those with rare allergies to mushroom-derived compounds. |
| Users of products with sensitive oils or actives for better preservation. | People sensitive to thiol-containing substances. |
| Individuals with acne-prone skin due to its zero comedogenic potential. | Individuals advised to patch test new antioxidants. |
Safety Notes
- EWG hazard score of 1 indicates low risk for use in cosmetics.
- Non-comedogenic rating of 0 supports use across skin types.
Frequently Asked Questions about Ergothioneine
What makes ergothioneine unique as an antioxidant?
Its stability and ability to target specific reactive species and metals set it apart from common antioxidants.
Is ergothioneine safe for daily skincare use?
Yes, it carries a low hazard rating and shows no comedogenic effects in formulations.
Where does ergothioneine come from naturally?
Primarily from fungi like those in mushrooms, where it occurs in high amounts.