Ergothioneine is an amino acid that is found mainly in mushrooms, as well as red and black beans. It is also found in animals that have eaten grasses containing ergothioneine. Ergothioneine is sometimes used as medicine.

People use ergothioneine for joint pain, liver damage, cataracts, Alzheimer disease, diabetes, heart disease, wrinkles, and other conditions, but there is no good scientific evidence to support these uses.
When taken by mouth: Ergothioneine is LIKELY SAFE when used in amounts found in foods. There isn't enough reliable information to know if ergothioneine is safe when used in larger amounts as medicine, or what the side effects might be.

Special Precautions & Warnings:

Pregnancy and breast-feeding: There isn't enough reliable information to know if ergothioneine is safe to use when pregnant or breast-feeding. Stay on the safe side and avoid use.


NatMed Pro rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, Ineffective, and Insufficient Evidence to Rate.
Likely effective Effectiveness definitions
Possibly effective Effectiveness definitions
Likely ineffective Effectiveness definitions
Possibly ineffective Effectiveness definitions
Insufficient evidence Effectiveness definitions
  • Heart disease. Some research suggests that higher levels of ergothioneine in the blood are linked to a lower risk of heart disease and death from heart disease. But it isn't clear if eating more foods containing ergothioneine or taking ergothioneine supplements will prevent heart disease or death.
  • Joint pain.
  • Liver damage.
  • Cataracts.
  • Alzheimer disease.
  • Diabetes.
  • Preventing wrinkles and reducing signs of aging, when applied to the skin.
  • Other conditions.
More evidence is needed to rate the effectiveness of ergothioneine for these uses.

Dosing & administration

The appropriate dose of ergothioneine depends on several factors such as the user's age, health, and several other conditions. At this time there is not enough scientific information to determine an appropriate range of doses for ergothioneine. Keep in mind that natural products are not always necessarily safe and dosages can be important. Be sure to follow relevant directions on product labels and consult your pharmacist or physician or other healthcare professional before using.

Interactions with pharmaceuticals

It is not known if Ergothioneine interacts with any medicines. Before taking Ergothioneine, talk with your healthcare professional if you take any medications.

Interactions with herbs & supplements

There are no known interactions with herbs and supplements.

Interactions with foods

There are no known interactions with foods.


Researchers are investigating ergothioneine to determine if it can reduce swelling (inflammation) in the lungs and damage in the liver, kidneys, and brain. has licensed monographs from TRC Healthcare.
This monograph was last reviewed on 23/11/2022 18:26:07 and last updated on 26/12/2012 18:16:05. Monographs are reviewed and/or updated multiple times per month and at least once per year.
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