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Ergothioneine
Bottom line
In our scoring, Ergothioneine rates weak evidence: the human evidence is thin for the body has a dedicated transporter for it. Our top-scored product is Toniiq Ergothioneine with MitoPrime 30mg (83/100), about $0.22 a day at a clinical dose of Typical supplements 5-30 mg/day. Bottom line: treat any benefit as unproven. This is our opinion, not medical advice; talk to your clinician before starting.
Here is the honest state of ergothioneine: your body treats it like something it wants to keep, and people with low blood levels tend to age worse - but no completed human trial has shown that taking it as a supplement makes you healthier or live longer.
- Evidence
- Weak Evidence
- Category
- Energy & Performance
- Best form
- synthetic/fermentation L-ergothioneine (branded ErgoActive or MitoPrime) or mushroom-extract-derived
- Effective dose
- Typical supplements 5-30 mg/day
- Lab tested
- 7 of 7 products
- Category
- Energy & Performance
- Best form
- synthetic/fermentation L-ergothioneine (branded ErgoActive or MitoPrime) or mushroom-extract-derived
- Effective dose
- Typical supplements 5-30 mg/day
- Lab tested
- 7 of 7 products
Key takeaways
- →Genuinely interesting biology: your body cannot make ergothioneine but has a dedicated transporter that actively hoards it - a strong hint it does something useful (Grundemann 2005).
- →The evidence is association, not proof. Low blood levels track with worse cognitive and cardiovascular outcomes in cohort studies, but no completed human trial shows a supplement improves anything - and low levels also just mark a mushroom-light diet.
- →The 'longevity vitamin' name is Bruce Ames's hypothesis (echoed by ingredient suppliers), not established fact. Toniiq (30 mg, branded MitoPrime, tested) is our Top Pick; Nutricost (30 mg, 120 ct) is the value pick.
- →Two dose tiers - 5 mg commodity vs 25-30 mg premium - and no outcome has an established effective dose, so more mg is not proven better. The cheapest way to raise your levels is to eat more mushrooms (king oyster and oyster are richest).
What Is Ergothioneine?
Here is the honest state of ergothioneine: your body treats it like something it wants to keep, and people with low blood levels tend to age worse - but no completed human trial has shown that taking it as a supplement makes you healthier or live longer. It is one of the more intriguing compounds in the longevity aisle, and it is also one of the easiest to oversell. Buy it, if you buy it, as a low-risk bet on early science, not as a proven anti-aging tool. For most people the more sensible move is to eat more mushrooms.
The reason researchers pay attention is a genuinely unusual fact of physiology. Ergothioneine is a diet-derived antioxidant your body cannot make on its own, yet you have a dedicated transporter (OCTN1) that is highly specific for it and pulls it into cells and tissues (Grundemann 2005). Evolution does not usually build a special uptake system for a molecule that does nothing, so the leading hypothesis is that it plays some functional, protective role. That is the seed of Bruce Ames's "longevity vitamin" idea (Ames 2018) - a hypothesis, and the origin of the label you see on supplement bottles, not a proven benefit. The label is echoed loudest by the ingredient suppliers who sell branded ergothioneine (ErgoActive, MitoPrime), which is worth keeping in mind.
What the human data actually shows is association, not proof. Blood ergothioneine falls with age and is lower in people with mild cognitive impairment (Cheah 2016); in a memory-clinic cohort of 470 patients, lower baseline levels predicted faster cognitive and functional decline over up to five years (Wu 2022). In a Swedish cohort of over 3,000 followed for around two decades, higher plasma ergothioneine tracked with lower cardiovascular and all-cause mortality (Smith 2020). These are real and consistent signals, but they share a stubborn limitation: low ergothioneine is also a marker of a diet light on mushrooms and vegetables, so it may simply be flagging the people who eat well. Raising your levels with a capsule has not been shown to change any of these outcomes. Association is not causation, and no trial has closed that gap yet.
Two practical notes. Humans get nearly all their ergothioneine from mushrooms - king oyster and oyster are richest, then shiitake and maitake, then plain white button, with only traces in organ meats, beans, and oat bran - and typical US intake is low, so eating more mushrooms is the cheapest way to raise your levels. If you do supplement, products split into two tiers: a 5 mg commodity dose (the amount the FDA cleared for food use) and a 25-30 mg premium dose. Because no health outcome has an established effective dose, "more milligrams" is not proven to be better - it is simply more. It appears very safe either way.
Does It Work? The Evidence
How A-F grades workErgothioneine earns a Weak Evidence rating - human evidence is thin across its claimed uses, the best-supported being the body has a dedicated transporter for it (a physiological role) (grade B). Each claim is graded individually below.
The body has a dedicated transporter for it (a physiological role)
Grundemann et al. 2005 (PNAS): discovery of the ergothioneine transporter (OCTN1/SLC22A4), highly specific for EGT - the body evolved a dedicated uptake system for this diet-derived compound, implying a functional role
Low blood ergothioneine associates with cognitive decline
Cheah et al. 2016 (Biochem Biophys Res Commun): plasma EGT declines with age and is lower in mild cognitive impairment; Wu et al. 2022 (Antioxidants), 470 memory-clinic patients: lower baseline EGT predicted faster cognitive and functional decline over up to 5 years - association only
Low ergothioneine associates with cardiovascular disease and mortality
Smith et al. 2020 (Heart), Malmo cohort n=3,236 over ~21 years: higher plasma EGT associated with lower risk (per 1-SD: ~15% lower coronary disease, ~21% lower CV mortality, ~14% lower all-cause mortality) - association only, and EGT also marks a mushroom/vegetable-rich diet
The 'longevity vitamin' hypothesis (conditionally-essential nutrient)
Ames 2018 (PNAS): proposes EGT as a conditionally-essential 'longevity vitamin' under triage theory - a hypothesis/opinion piece, the ORIGIN of the label, not proof of benefit
Raising ergothioneine via supplements improves a human health outcome
No completed randomized controlled trial has shown that supplementing ergothioneine prevents disease, slows cognitive decline, or extends healthspan in people - the human evidence is entirely observational so far
| Grade | Claimed Benefit | Key Studies | Our Verdict |
|---|---|---|---|
| B | The body has a dedicated transporter for it (a physiological role) | Grundemann et al. 2005 (PNAS): discovery of the ergothioneine transporter (OCTN1/SLC22A4), highly specific for EGT - the body evolved a dedicated uptake system for this diet-derived compound, implying a functional role | Early Signal |
| C | Low blood ergothioneine associates with cognitive decline | Cheah et al. 2016 (Biochem Biophys Res Commun): plasma EGT declines with age and is lower in mild cognitive impairment; Wu et al. 2022 (Antioxidants), 470 memory-clinic patients: lower baseline EGT predicted faster cognitive and functional decline over up to 5 years - association only | Early Signal |
| C | Low ergothioneine associates with cardiovascular disease and mortality | Smith et al. 2020 (Heart), Malmo cohort n=3,236 over ~21 years: higher plasma EGT associated with lower risk (per 1-SD: ~15% lower coronary disease, ~21% lower CV mortality, ~14% lower all-cause mortality) - association only, and EGT also marks a mushroom/vegetable-rich diet | Early Signal |
| D | The 'longevity vitamin' hypothesis (conditionally-essential nutrient) | Ames 2018 (PNAS): proposes EGT as a conditionally-essential 'longevity vitamin' under triage theory - a hypothesis/opinion piece, the ORIGIN of the label, not proof of benefit | Not There Yet |
| F | Raising ergothioneine via supplements improves a human health outcome | No completed randomized controlled trial has shown that supplementing ergothioneine prevents disease, slows cognitive decline, or extends healthspan in people - the human evidence is entirely observational so far | Not There Yet |
How to Choose: Forms, Doses & What Matters
Clinical dose: Typical supplements 5-30 mg/day; no established effective dose for any health outcome
Best forms: synthetic/fermentation L-ergothioneine (branded ErgoActive or MitoPrime) or mushroom-extract-derived, 5 mg (commodity) vs 25-30 mg (premium) are the two tiers, or just eat more mushrooms - oyster and king oyster are richest
There is no established effective dose for any health outcome, so dosing is a judgment call, not a prescription. Products cluster in two tiers: a 5 mg commodity dose (the amount cleared for food use) and a 25-30 mg premium dose. More milligrams is not proven to do more here - it is simply more - so a modest dose is a defensible starting point. Ergothioneine is water-soluble and does not require food, though taking it with a meal is fine. The genuinely cheapest and most food-first approach is to eat more mushrooms: king oyster and oyster varieties are the richest sources, followed by shiitake and maitake, then ordinary white button, and cooking does not destroy it. Whichever route you choose, treat it as an experiment with an open question mark, not a proven protocol.
Who Should Take Ergothioneine?
This suits people who follow longevity science, understand they are betting on association data rather than proven human results, and want a low-cost, well-tolerated experiment. It is a more reasonable curiosity if you eat few mushrooms, since diet is nearly the only source and typical intake is low - though in that case simply adding mushrooms to your meals does the same job for less. People drawn to antioxidant and mitochondrial-support ideas may find the mechanism appealing, as long as they hold the human evidence at its honest weight: promising, unproven. If you want a supplement with completed human trials behind it, this is not one of them yet.
Who Should Avoid It?
Not for everyone
Side Effects & Safety
Product Scores
7 products scored on dosing accuracy, third-party testing, cost per effective dose, and label transparency.
The Scorecard: 7 Products Compared
Toniiq Ergothioneine with MitoPrime 30mg
Toniiq
$19.97 ÷ 91 days at 30mg/day (1 serving × 30mg)
The cleanest quality story here: a branded, purity-specified ingredient plus brand-stated testing and a 90-count bottle. In our view the best single product for someone who wants a proper ergothioneine dose - though the honest ceiling is that the compound's human benefits are still unproven.
Prices checked 2026-07-07. Cost shown is per clinically effective daily dose, not per pill.
Nutricost L-Ergothioneine 30mg
Nutricost$16.95 ÷ 121 days at 30mg/day (1 serving × 30mg)
The value pick: the full 30 mg premium dose at the lowest cost per day here, from a brand that states third-party testing. Uses a generic ergothioneine rather than a branded ingredient, which is the main thing separating it from our Top Pick.
Prices checked 2026-07-07. Cost shown is per clinically effective daily dose, not per pill.
California Gold Nutrition Ergothioneine 5mg
California Gold Nutrition
$12.95 ÷ 92 days at 5mg/day (1 serving × 5mg)
The low-dose, low-cost entry point: 5 mg is the food-use amount and among the cheapest per day here, with published COAs from a reputable house brand. It is only this cheap because the dose is smaller, so we do not treat it as the outright value pick against the 30 mg products - but for a modest daily amount it is a sensible, transparent choice.
Prices checked 2026-07-07. Cost shown is per clinically effective daily dose, not per pill.
Double Wood Ergothioneine 30mg
Double Wood
$12.95 ÷ 59 days at 30mg/day (1 serving × 30mg)
A transparent premium-dose option with published COAs from a recognized value brand. The smaller 60-count bottle makes it pricier per day than the 120-count value pick, but the disclosure is a plus.
Prices checked 2026-07-07. Cost shown is per clinically effective daily dose, not per pill.
ProHealth Longevity Ergothioneine 5X Strength 25mg
ProHealth Longevity
$39.95 ÷ 30 days at 25mg/day (1 serving × 25mg)
A premium longevity-brand option at a premium price. The dose and testing claims are fine, but the small bottle makes it the costliest way to reach a premium dose on this list.
Prices checked 2026-07-07. Cost shown is per clinically effective daily dose, not per pill.
Real Mushrooms ERGO+ 20mg per serving
Real Mushrooms
$34.95 ÷ 30 days at 20mg/day (1 serving × 20mg)
The whole-food option for people who prefer a mushroom matrix over an isolated compound. It costs more per milligram of ergothioneine because the beta-glucans and mushroom extract come along for the ride, which is either a bonus or a dilution depending on what you want.
Prices checked 2026-07-07. Cost shown is per clinically effective daily dose, not per pill.
Life Extension Essential Youth L-Ergothioneine 5mg
Life Extension$18.00 ÷ 30 days at 5mg/day (1 serving × 5mg)
A 5 mg option from a well-known longevity brand with published COAs. The small 30-count bottle pushes the per-day cost above the other commodity-dose choices, so it appeals mainly to existing Life Extension buyers.
Prices checked 2026-07-07. Cost shown is per clinically effective daily dose, not per pill.
Full Comparison
| Category | Toniiq Ergothioneine with MitoPrime 30mg Toniiq | Nutricost L-Ergothioneine 30mg Nutricost | California Gold Nutrition Ergothioneine 5mg California Gold Nutrition | Double Wood Ergothioneine 30mg Double Wood | ProHealth Longevity Ergothioneine 5X Strength 25mg ProHealth Longevity | Real Mushrooms ERGO+ 20mg per serving Real Mushrooms | Life Extension Essential Youth L-Ergothioneine 5mg Life Extension |
|---|---|---|---|---|---|---|---|
| Brand Score | 83/100Winner | 80/100 | 77/100 | 77/100 | 73/100 | 71/100 | 69/100 |
| Dosing & Form | 23/25Winner | 23/25 | 19/25 | 23/25 | 22/25 | 20/25 | 19/25 |
| Purity | 18/25Winner | 18/25 | 18/25 | 16/25 | 17/25 | 16/25 | 17/25 |
| Value | 21/25 | 22/25Winner | 20/25 | 18/25 | 13/25 | 14/25 | 13/25 |
| Transparency | 21/25Winner | 17/25 | 20/25 | 20/25 | 21/25 | 21/25 | 20/25 |
| Cost/Day | $0.22 | $0.14Winner | $0.14 | $0.22 | $1.33 | $1.16 | $0.60 |
| Dose/Serving | 30mg | 30mg | 5mg | 30mg | 25mg | 20mg | 5mg |
| Form | Capsule (MitoPrime L-ergothioneine, 98% purity) | Capsule (L-ergothioneine) | Veg capsule (L-ergothioneine) | Capsule (fermentation-derived L-ergothioneine) | Capsule (L-ergothioneine) | Capsule (fermented L-ergothioneine + golden oyster mushroom extract) | Capsule (L-ergothioneine) |
| Third-Party Tested | ✓ Yes | ✓ Yes | ✓ Yes | ✓ Yes | ✓ Yes | ✓ Yes | ✓ Yes |
| Proprietary Blend | No | No | No | No | No | No | No |
Frequently Asked Questions
Does ergothioneine actually work?
For raising blood antioxidant levels, yes - it is absorbed and actively retained via a dedicated transporter. For improving a health outcome, the honest answer is that no one has proven it. The human evidence is observational: people with low ergothioneine tend to have worse cognitive and cardiovascular outcomes in cohort studies, but no completed trial has shown that taking a supplement changes those outcomes. And because low levels also mark a diet light on mushrooms and vegetables, some of that association may just be flagging people who eat well. It is a reasonable early-science bet, not an established benefit.
Why is ergothioneine called 'the longevity vitamin'?
The label comes from biochemist Bruce Ames, who in 2018 proposed ergothioneine as a conditionally-essential 'longevity vitamin' under his triage theory - the idea that some nutrients get rationed toward short-term survival at the expense of long-term health. It is a hypothesis, and it is the origin of the phrase you see on bottles, not a proven fact. The label is repeated most loudly by the companies that sell branded ergothioneine ingredients, so it is worth taking as a marketing-adjacent claim rather than a settled scientific conclusion.
Should I take a supplement or just eat mushrooms?
For most people, mushrooms. Humans cannot make ergothioneine and get nearly all of it from the diet, and mushrooms are by far the richest source - king oyster and oyster varieties highest, then shiitake and maitake, then plain white button. Cooking does not destroy it. Since no health outcome has an established effective dose, there is no proven advantage to a capsule's higher number over a mushroom-rich diet, and the food route is cheaper and comes with fiber and other nutrients. A supplement mainly makes sense if you rarely eat mushrooms and want a consistent daily amount.
How much ergothioneine should I take?
There is no established effective dose for any health outcome, so this is genuinely unsettled. Supplements come in two tiers: a 5 mg commodity dose (the amount the FDA cleared for food use) and a 25-30 mg premium dose. More milligrams is not proven to be better - it is simply more - so a modest dose is a perfectly defensible starting point. The compound is water-soluble and does not require food. If your goal is longevity insurance rather than treating a specific problem, the low tier is a reasonable and inexpensive place to begin.
Is ergothioneine safe?
It appears very safe and well tolerated. The synthetic L-ergothioneine used in many supplements carries FDA GRAS status for food use (up to 5 mg per serving), and short human studies have reported no serious adverse effects. The limitations are honest ones: long-term, high-dose human safety data is limited because the compound simply has not been studied over many years, and no drug interactions are well documented - though that thin interaction record reflects limited study rather than proven safety. There is no data in pregnancy or breastfeeding, so those groups should avoid it.
What is MitoPrime and does it matter?
MitoPrime is a branded, high-purity L-ergothioneine ingredient (from the supplier NNB), and ErgoActive is a comparable branded ingredient from another supplier. The practical upside of a branded ingredient is a stated purity specification and, sometimes, the ingredient used in the small human studies that exist - which is a modest real quality signal versus an unspecified generic. It does not change the underlying evidence picture: branded or generic, ergothioneine's human benefits remain associational and unproven. We treat the branded, tested products as a small quality edge, not as evidence that the compound works.
Related Reading
Sources
- Grundemann D, et al. Discovery of the ergothioneine transporter. Proc Natl Acad Sci USA. 2005;102(14):5256-5261.
- Cheah IK, et al. Ergothioneine levels in an elderly population decrease with age and incidence of cognitive decline; a risk factor for neurodegeneration? Biochem Biophys Res Commun. 2016;478(1):162-167.
- Wu LY, et al. Low Plasma Ergothioneine Predicts Cognitive and Functional Decline in an Elderly Cohort Attending Memory Clinics. Antioxidants (Basel). 2022;11(9):1717.
- Smith E, et al. Ergothioneine is associated with reduced mortality and decreased risk of cardiovascular disease. Heart. 2020;106(9):691-697.
- Ames BN. Prolonging healthy aging: Longevity vitamins and proteins. Proc Natl Acad Sci USA. 2018;115(43):10836-10844.
Scores and tiers are our independent opinion, formed by applying a published rubric to label data, third-party certifications, and the research record. They are not statements of objective fact about a product and not a lab test. Where we report a brand-specific fact, it comes from a cited source or a public certification; where verification is missing, we say so rather than assume a result.
FDA Disclaimer: These statements have not been evaluated by the Food and Drug Administration. Dietary supplements are not intended to diagnose, treat, cure, or prevent any disease. Always consult with a qualified healthcare professional before starting any supplement regimen.