Evidence-based·Last reviewed May 30, 2026·How we grade evidence

Ergothioneine

Amino-acid

Useful mainly for people interested in a dietary antioxidant with a dedicated human transporter (early evidence).

Quick decision guide

May help most

people interested in a dietary antioxidant with a dedicated human transporter (early evidence)

Common dosing range

5–30 mg/day

When to expect effects

Weeks (builds tissue stores)

Watch out for

limited long-term and clinical-outcome data

What is it

Ergothioneine (L-ergothioneine) is a naturally occurring amino acid antioxidant produced primarily by fungi and some bacteria. Humans cannot make it, but we have a specific transporter (OCTN1/SLC22A4) that concentrates it in tissues, suggesting a biological role.

Is it worth it for you?

Use this as a quick fit check, not a diagnosis.

Worth considering if…

you want to raise intake of a well-retained dietary antioxidant

you are comfortable with early, mechanism-level evidence

you prefer a food-derived compound (also found in mushrooms)

Probably skip if…

you expect proven disease prevention or anti-aging outcomes

you want strong clinical-trial backing

you would rather get it from mushrooms in the diet

Evidence at a glance

Goal	Effect	Best fit	Time
antioxidant status and healthy aging Limited Evidence	Unproven for clinical outcomes	adults interested in dietary antioxidant intake	Weeks

antioxidant status and healthy aging

Limited Evidence

Effect: Unproven for clinical outcomes
Best fit: adults interested in dietary antioxidant intake
Time: Weeks

Evidence for 1 use

AI-assisted evidence assessment — talk to your doctor before relying on any single supplement.

antioxidant status and healthy aging

Mechanism only

Limited Evidence

Ergothioneine is a stable antioxidant that humans actively transport and concentrate in tissues, and blood levels decline with age and in some diseases. Current evidence is largely mechanistic and observational; causal links to healthy aging or disease prevention are not established. No clinical trials demonstrate symptom or disease-outcome benefits.

Effect size

Unproven for clinical outcomes

Time to effect

Weeks

Best fit

adults interested in dietary antioxidant intake

Less likely

people expecting measurable disease prevention

Bottom line: Biologically interesting as a retained antioxidant, but clinical benefits remain unproven.

SourceBorodina et al., 2020 — PMC

How it works

Ergothioneine accumulates in tissues exposed to oxidative stress, such as the eyes, liver, kidneys, bone marrow, and red blood cells. It is a strong antioxidant that resists auto-oxidation, making it stable in storage and at physiologic levels. Proposed roles include protection of mitochondria, scavenging reactive oxygen species, and possible support for healthy aging. Blood levels decline with age and in some diseases (like Crohn's and Parkinson's), but causal relationships are still being explored.

How to take it

1. Typical dose

5–30 mg/day

2. Timing

any time of day

3. With food

with or without food

4. How long to try

ongoing daily intake builds tissue stores

What to track

general tolerance

dietary mushroom intake as an alternative source

1 commercial form

Compare the main delivery options and what they’re best suited for.

L-ergothioneine (MitoPrime, ErgoActive)

Used in antioxidant and longevity-focused supplements.

Concentrated by OCTN1 transporter

Safety

Know the common side effects, key cautions, and who should avoid it.

Common side effects

none commonly reported at typical doses

Who should avoid it

no specific group beyond general caution in pregnancy/breastfeeding for concentrated supplements

Pregnancy & breastfeeding

Dietary intake from mushrooms is fine; data for concentrated supplements in pregnancy are limited.

Interactions

No well-established drug interactions.

Food sources

Food	Amount	%DV
Mushrooms (especially shiitake, oyster, porcini, king oyster)	1 cup cooked	—

Mushrooms (especially shiitake, oyster, porcini, king oyster)

Amount: 1 cup cooked
%DV: —

Choosing a product

What to look for on the label — and what to be skeptical of.

Look for…

L-ergothioneine specified

clear per-serving mg amount

GRAS-status ingredient (e.g., MitoPrime)

Be skeptical of…

anti-aging cure

prevents Parkinson's or Crohn's

longevity guarantee

Frequently asked questions

Can I get enough ergothioneine from food?⌄

Mushrooms are the main dietary source. Eating mushrooms regularly contributes meaningful amounts.

Is ergothioneine an essential nutrient?⌄

Not formally classified as essential, but its dedicated transporter and tissue accumulation have led some researchers to call it a 'longevity vitamin'.

References by claim

antioxidant status and healthy aging

Borodina et al., 2020 — PMC (2020) link

Track Ergothioneine with Pilora

Set up dose reminders, check interactions, and join the community in the Pilora iPhone app.

Coming to App Store

Evidence-based·Last reviewed May 30, 2026·Evidence current as of May 30, 2026·How we grade evidence

Disclaimer: These statements have not been evaluated by the FDA. This page is educational, not a substitute for personalized medical advice. Evidence grades are AI-assisted assessments — talk to your doctor before starting any new supplement, especially if you’re pregnant, breastfeeding, on medications, or managing a chronic condition.