Ergothioneine at a glance

  • Potent antioxidant abundant in certain types of mushrooms
  • Helps skin look younger in multiple ways
  • Fades signs of discoloration
  • Offers soothing benefits

Ergothioneine description

Ergothioneine is a derivative of the amino acid histidine synthesized in nature by various bacteria and fungi. It occurs in most types of mushrooms with naturally high amounts detected in oyster, porcini, portobello, white button and shiitake types. Red beans, black beans, garlic and oat bran are other food sources, but a bio-identical form can be lab-synthesized and has proven to be safe. Several studies have shown that ergothioneine is a potent antioxidant, capable of helping skin look younger when exposed to environmental stressors and sources of oxidative damage. One of the ways ergothioneine works on skin is by helping to protect its endogenous (naturally occurring) antioxidants from degrading, thus enabling it to maintain its defenses for longer periods of time. Ergothioneine also has a surface inhibitory effect on an enzyme that plays a role in fueling excess melanin within skin’s uppermost layers. In doing so, ergothioneine plays a supporting role helping to fade discolorations. Usage levels of ergothioneine in skin care range from 0.1–1% when supplied in a water-based solution with the antioxidant having an activity level of 0.05%--a testimony to this ingredient’s impressive potency.

Ergothioneine references

  • Experimental Gerontology, December 2022, pages 1–11
  • Processes, July 2021, pages 1–13
  • Redox Biology, June 2021, pages 1–10
  • International Journal of Molecular Sciences, March 2021, pages 1–11
  • Experimental Cell Research, March 2021, ePublication
  • Polymers, January 2021, pages 1–9
  • Oxidative Medicine and Cellular Longevity, 2020, pages 1–13

Peer-reviewed, substantiated scientific research is used to assess ingredients in this dictionary. Regulations regarding constraints, permitted concentration levels and availability vary by country and region.

Ingredient ratings


Proven and supported by independent studies. Outstanding active ingredient for most skin types or concerns.


Necessary to improve a formula's texture, stability, or penetration.


Generally non-irritating but may have aesthetic, stability, or other issues that limit its usefulness.


There is a likelihood of irritation. Risk increases when combined with other problematic ingredients.


May cause irritation, inflammation, dryness, etc. May offer benefit in some capability but overall, proven to do more harm than good.


We couldn't find this in our ingredient dictionary. We log all missing ingredients and make continuous updates.

Not rated

We have not yet rated this ingredient because we have not had a chance to review the research on it.