Mushroom Nutrition Facts: A Complete Species-by-Species Guide

Mushroom Nutrition & Cooking

35% lower all-cause mortality

In NHANES III, 15,546 US adults were followed for a mean of 19.5 years. Modelling one daily serving of mushrooms in place of one serving of processed or red meat was associated with a 35% lower risk of death from any cause (HR 0.65).

Ba et al., Nutrition Journal, 2021

0.15–7.27

mg/g dry weight — the full measured ergothioneine range across mushroom species (Kalaras et al., 2017)

491 μg

vitamin D2 per 100g after UV-B exposure, up from under 1 μg (Urbain et al., 2011)

18

peer-reviewed studies cited and checked against their source abstracts

Ba et al., Nutrition Journal, 2021

View as image ↗

Mushrooms sit in an unusual position in nutrition science. They are not a vegetable and not a plant. They belong to a separate kingdom of life, and that matters nutritionally because fungi make compounds that plants and animals do not. The best known of these is ergothioneine, a sulfur-containing amino acid that humans cannot synthesise and for which the body maintains a dedicated transporter.

Mushroom nutrition facts also vary sharply by species. A button mushroom and a maitake are different organisms with different nutritional profiles, and in the case of vitamin D the gap between them is more than a hundredfold. This guide covers the species comparison data, the unique nutrients, and the population-level evidence — with each number checked against the study that is supposed to support it.

A note on method: several figures that circulate widely in mushroom nutrition writing do not appear in the papers they are attributed to. Where that is the case, this guide says so and gives the measured value instead.

The Mortality Data Most Mushroom Nutrition Articles Ignore

Most mushroom nutrition content focuses on individual nutrients in isolation. What is largely missing is the long-term population data on what happens to people who eat mushrooms regularly.

Ba and colleagues published a prospective cohort analysis in Nutrition Journal in 2021 using NHANES III. They analysed 15,546 participants whose mushroom intake was captured by a single 24-hour dietary recall, linked to National Death Index records from 1988 to 2015. Over a mean follow-up of 19.5 years, 5,826 deaths were recorded. After adjustment for demographics, lifestyle, overall diet quality and total energy, mushroom consumers had a lower risk of all-cause mortality than non-consumers (HR 0.84, 95% CI 0.73–0.98), with a dose-response trend (P-trend = 0.03). Modelling one daily serving of mushrooms in place of one serving of processed or red meat gave an adjusted HR of 0.65 (95% CI 0.50–0.84) — the 35% figure that headlines this article.^[1]

One detail rarely carried over into consumer coverage: when the same paper examined cause-specific mortality, no individual cause reached statistical significance. The result is an all-cause finding, not a cardiovascular or cancer finding.

The same group published a second Nutrition Journal paper in 2021 using continuous NHANES 2003–2014, following 30,378 participants over a mean 6.7 years. Here the association with all-cause mortality was not statistically significant (HR 0.84, 95% CI 0.67–1.06). The authors then pooled their result with four other cohort studies, covering 601,893 individuals in total, and that meta-analysis did find a significant association (pooled risk ratio 0.94, 95% CI 0.91–0.98).^[2]

Jung and colleagues added an independent replication in 2023 using the Korean Genome and Epidemiology Study: 152,828 adults aged 40 and over, mean follow-up 11.6 years, 7,085 deaths. The pattern is more specific than it is usually reported. In men, eating mushrooms less than once a week (HR 0.858) or one to three times a week (HR 0.902) was associated with lower all-cause mortality, with parallel reductions in cardiovascular mortality. In women, the same two categories showed lower all-cause mortality. Notably, the highest intake category — three or more servings per week — was not associated with lower mortality in either sex.^[14]

Mortality Evidence

The 35% Figure Is the Strongest Estimate, Not the Typical One

Every mushroom-and-mortality estimate cited in this article, drawn with its 95% confidence interval. Anything whose interval touches the dashed null line at 1.0 did not reach statistical significance. The headline 35% reduction (HR 0.65) comes from a substitution model, and it sits well to the left of every directly measured comparison.

NHANES III

n = 15,546 · mean 19.5 y

Any mushroom intake vs none

0.84

0.73–0.98

NHANES III

substitution model

1 serving/day replacing processed or red meat

0.65

0.50–0.84

NHANES 2003–14

n = 30,378 · mean 6.7 y

Any mushroom intake vs none

0.84

0.67–1.06

Meta-analysis

5 cohorts · 601,893 people

Pooled all-cause mortality

0.94

0.91–0.98

KoGES (Korea)

men · n = 152,828 total

Under 1 serving/week vs none

0.86

0.79–0.93

KoGES (Korea)

men

1–3 servings/week vs none

0.90

0.82–0.99

0.5

0.6

0.7

0.8

0.9

1.0

1.1

← lower risk

higher risk →

Statistically significantInterval crosses 1.0 — not significant

Read it this way: the direction is consistent — every point estimate falls below 1.0, across three cohorts on two continents. The magnitude is not. The largest single cohort here (KoGES, 152,828 people) found reductions of roughly 10–14%, and found nothing at all in its highest intake category. All of these are observational.

Sources: Ba DM et al. (2021), Nutrition Journal 20(1):38 — NHANES III; Ba DM et al. (2021), Nutrition Journal 20(1):80 — continuous NHANES 2003–2014 plus meta-analysis of five cohorts; Jung S et al. (2023), Food & Function 14(19):8829–8837 — Korean Genome and Epidemiology Study. Hazard ratios and risk ratios as reported in each abstract.

Population Evidence

Ba et al. (2021) · Nutrition Journal

Population

15,546 US adults from NHANES III (1988–1994), mean age 44.3 years, followed to 2015

Intervention

Self-reported mushroom intake from a single 24-hour dietary recall

Comparator

Participants reporting no mushroom intake

Finding

All-cause mortality HR 0.84 (95% CI 0.73–0.98) for mushroom consumers. Substituting one daily serving of mushrooms for processed or red meat: HR 0.65 (95% CI 0.50–0.84). No cause-specific mortality association reached significance.

positive Observational and based on a single day of dietary recall, which is a weak measure of habitual intake. The substitution result is a statistical model, not an intervention that was actually tested.

Ba DM et al. (2021), Nutrition Journal 20(1):38

The honest caveat: all three are observational. Mushroom consumers may differ from non-consumers in diet quality and lifestyle, and covariate adjustment cannot eliminate every confounder. Two of the three rely on 24-hour dietary recalls, which capture a single day rather than habitual intake. The consistency of direction across independent cohorts on two continents is worth something. It is not a controlled trial, and no trial has tested whether adding mushrooms to a diet changes mortality.

For the full analysis of mushrooms as a superfood and how the evidence compares to vegetables, see Mushrooms as a Superfood: Nutritional Density Compared to Vegetables.

Mushroom Nutrition by Species: The Comparison Table

Mushrooms are not one food. The single largest nutritional difference between species is vitamin D, and the best measured dataset comes from Phillips and colleagues, who assayed vitamin D2 and sterols in 10 types of mushrooms sampled nationwide in the United States to update the USDA nutrient database.^[6]

* Calorie and protein figures are USDA FoodData Central reference values for raw mushrooms, not measurements from the cited studies. Vitamin D2 and ergosterol columns are from Phillips et al. (2011). Phillips reported significant variability between composite samples for some types, so treat these as ranges rather than fixed values.

Three things are worth drawing out of this table.

The vitamin D spread is the headline. Morel, chanterelle and maitake contained 5.2–28.1 μg/100 g without any UV treatment — up to roughly 100 times the level in white button, crimini, portabella or enoki. This is the opposite of how mushroom vitamin D is usually described. It is not simply that "mushrooms need UV light"; several species that are typically wild-harvested or grown with light exposure already carry substantial vitamin D2 when you buy them.

UV treatment closes the gap for the common species. UV-treated portabella reached 3.4–20.9 μg/100 g, moving A. bisporus from negligible into the same band as the naturally high species.

Ergosterol is the raw material, not the vitamin. Shiitake (84.9 mg/100 g) and maitake (79.2 mg/100 g) had the most ergosterol, and white button composites the least. Ergosterol is the precursor that UV converts into vitamin D2, so a high-ergosterol species has more headroom for UV enrichment — but ergosterol itself is not vitamin D.

For the complete breakdown across all macronutrients and micronutrients, see Mushroom Macronutrients and Micronutrients: A Complete Nutritional Breakdown by Species.

Ergothioneine: The Compound Fungi Are Richest In (And What the Data Actually Shows)

Ergothioneine is the most distinctive nutrient in mushrooms. It is a sulfur-containing compound that humans cannot synthesise, produced by fungi and certain bacteria. The human body has a dedicated transport protein, OCTN1 (SLC22A4), that moves ergothioneine from food into tissues — and the existence of a specialised transporter for a dietary compound is the main reason researchers treat it as biologically interesting rather than incidental.

Kalaras and colleagues measured ergothioneine and glutathione across mushroom species in 2017. What they reported is a range: ergothioneine varied from 0.15 to 7.27 mg per gram of dry weight, roughly a 48-fold spread between the lowest and highest species, and correlated with glutathione levels (r = 0.62, P < 0.001). Two secondary findings are practically useful: both antioxidants were more concentrated in the cap (pileus) than the stem (stipe), and A. bisporus harvested in the third cropping flush contained more of both than the first flush, possibly as a response to oxidative stress.^[4]

Claim Provenance

Does porcini contain 628 μg/g of ergothioneine?

The claim

“Porcini mushrooms contain 628 μg/g of ergothioneine, the highest of any food ever measured, and mushrooms contain 10 to 100 times more ergothioneine than any other food.”

Attributed across nutrition media to Kalaras et al. (2017), Food Chemistry.

What research shows

Unsupported

Neither figure appears in that paper. Kalaras et al. report ergothioneine spanning 0.15 to 7.27 mg/g dry weight across species — so 628 μg/g (0.628 mg/g) is not the maximum they measured; it sits in the lower-middle of their own range. The paper does not name porcini, does not state a species count, and does not give a 10–100x multiplier.

The underlying direction is defensible: the paper concludes mushrooms should be considered an excellent dietary source, and Ey et al. (2007) found the highest food concentrations in specialty mushrooms. But that same survey detected meaningful ergothioneine in kidney, liver, black and red beans, and oat bran — so mushrooms are the richest dietary source, not the only one.

Kalaras MD et al. (2017), Food Chemistry 233:429–433; Ey J et al. (2007), J Agric Food Chem 55(16):6466–74

Claim Provenance

The Famous Ergothioneine Number Is Below Its Own Source’s Maximum

All values normalised to milligrams per gram of dry weight. The shaded band is the range Kalaras et al. (2017) actually report across mushroom species. The claim that porcini contains 628 μg/g and that this is the highest figure ever measured lands inside the lower part of that band — it cannot simultaneously be the maximum of a range whose stated maximum is more than eleven times larger.

Kalaras measured range

Kalaras 2017 — lowest species measured

0.15 mg/g

0.15 mg/g dry weight

The circulating claim: "628 μg/g, the highest ever measured"

0.628 mg/g

0.628 mg/g — attributed to Kalaras 2017, absent from that paper

Tsiantas 2021 — golden oyster, LC-MS verified

0.822 mg/g

822.1 mg/kg = 0.822 mg/g dry weight

Kalaras 2017 — highest species measured

7.27 mg/g

7.27 mg/g dry weight

What the paper does say: ergothioneine varies about 48-fold across species; it correlates with glutathione (r = 0.62, P < 0.001); caps hold more than stems; and third-flush A. bisporus holds more than first-flush. The paper names no species as a record-holder, gives no species count, and offers no “10–100× any other food” multiplier.

Why it keeps propagating: assay methods are not interchangeable. Tsiantas et al. found UV-visible spectrometry produced invalid ergothioneine results because other mushroom constituents absorb in the same region. Figures generated by different methods get compared as though they were equivalent, and the discrepancies survive because almost nobody re-opens the source paper.

Sources: Kalaras MD et al. (2017), Food Chemistry 233:429–433 — “Mushrooms: A rich source of the antioxidants ergothioneine and glutathione.” Tsiantas K et al. (2021), Molecules 26(7). Bars use square-root scaling so the low end of the range stays legible.

For species-level numbers that can be checked, Tsiantas and colleagues quantified ergothioneine by LC-MS across three cultivated species in 2021 and found Pleurotus citrinopileatus (golden oyster) highest at 822.1 ± 20.6 mg/kg dry sample — that is 822 μg/g — ahead of P. ostreatus and A. bisporus. Their broader point is methodological and matters for anyone comparing published figures: UV-visible spectrometry, still used in some analyses, gave invalid results because other mushroom constituents absorb in the same region. Numbers produced by different assays are not directly comparable.^[18]

Ey and colleagues surveyed ergothioneine across common foods by LC-MS/MS in 2007. Specialty mushrooms had the highest concentrations, but kidney, liver, black and red beans and oat bran also contained detectable amounts. The same paper is a useful brake on enthusiasm: in OCTN1-expressing cells, ergothioneine protected only against copper(II)-induced toxicity and was far less potent than glutathione, leading the authors to conclude it is not part of the general intracellular antioxidant thiol defence system.^[17]

Is dietary ergothioneine absorbed? Weigand-Heller and colleagues tested this in 2012 in a randomised crossover pilot in 10 healthy men given 8 g or 16 g of mushroom powder in a test meal. Ergothioneine was bioavailable, measured as uptake into red blood cells postprandially, and there was a blunting of the postprandial triglyceride response at both doses. Two results cut against the usual retelling: total ORAC antioxidant capacity decreased after the mushroom meals rather than increasing, and the study did not demonstrate a reduction in inflammatory markers.^[5] So eating mushrooms demonstrably raises ergothioneine in the body — but the acute antioxidant story is not as clean as it is usually told.

Lam-Sidun and colleagues reviewed the cardiometabolic evidence in 2021. Ergothioneine accumulates preferentially in tissues under oxidative stress and has a demonstrated cytoprotectant effect, which is why a therapeutic role in cardiometabolic disease has been proposed. The review is explicit about the limits: in vivo effects in whole organisms are not clear, and there are no well-defined clinical prevention or intervention trials of ergothioneine.^[12] The mechanistic pathway from mushroom intake to the NHANES mortality signal remains a hypothesis.

For a deeper dive into ergothioneine's mechanisms, see Ergothioneine: The Most Selective Antioxidant in Your Body.

Vitamin D From a Fungus: How It Works and What the Trials Found

Mushrooms can be a meaningful dietary source of vitamin D, and almost no other non-fortified, non-animal food can make that claim. The mechanism mirrors what human skin does in sunlight.

The relevant compound in mushroom cell walls is ergosterol. Under ultraviolet light it undergoes photochemical conversion to vitamin D2 (ergocalciferol), structurally parallel to human skin converting 7-dehydrocholesterol to vitamin D3 under UV-B.

Koyyalamudi and colleagues characterised this conversion in 2009. Exposing fresh button mushrooms to UV-C produced a time-dependent rise in vitamin D2 — 6.6, 15.6 and 23.1 μg/g solids after 2.5, 5 and 10 minutes at 0.125–0.25 J/cm² — and the vitamin D2 was stable in storage for eight days with no significant discolouration. This was a laboratory and rat study, not a human trial: bioavailability was assessed in rats, not people.^[7] It is frequently miscited in consumer coverage as a human clinical trial; it was not.

The first human demonstration came from Urbain and colleagues in 2011. They irradiated fresh mushrooms at 1.5 J/cm² of UV-B, raising vitamin D2 from under 1 to 491 μg/100 g, and made them into a soup. Twenty-six young adults with serum 25(OH)D at or below 50 nmol/l were randomised over five winter weeks to mushroom soup delivering 28,000 IU of vitamin D2 weekly, an equivalent D2 supplement, or placebo. Serum 25(OH)D was significantly higher in the mushroom group than placebo by two weeks, and rose at a similar weekly rate in the mushroom group (3.9 nmol/l per week) and the supplement group (4.7 nmol/l per week).^[15]

Clinical Evidence

Urbain et al. (2011) · European Journal of Clinical Nutrition

Population

26 young adults with serum 25(OH)D at or below 50 nmol/l, studied over winter

Intervention

UV-B irradiated mushroom soup delivering 28,000 IU vitamin D2 per week for 5 weeks

Comparator

Equivalent D2 supplement, and placebo

Finding

Serum 25(OH)D rose 3.9 nmol/l per week on mushrooms versus 4.7 nmol/l per week on the supplement — statistically similar. Mushroom group significantly above placebo by week 2.

positive Small (26 participants), single-blinded, and short. It establishes bioavailability, not long-term sufficiency.

Urbain P et al. (2011), Eur J Clin Nutr 65(8):965–71

That result is genuinely important, but it is not the whole picture. Mehrotra and colleagues ran a 16-week randomised trial in 2014 in 43 vitamin-D-deficient prediabetic adults, comparing daily entrées made with UVB-treated mushrooms (labelled 600 IU or 4000 IU of D2) against untreated mushrooms plus D3 supplements at matched label doses. The UVB mushroom doses were significantly lower after cooking, and produced only modest or no increase in 25(OH)D2 or total 25(OH)D relative to the D3 control groups.^[16]

Trial Divergence

Two Randomised Trials, Two Answers, Four Design Differences

Both trials fed people UV-treated mushrooms and measured serum 25(OH)D. One found mushrooms performed like a supplement; the other found modest or no benefit. Reading the design columns side by side shows why — and which question each trial actually answered.

Urbain et al. 2011

Eur J Clin Nutr · n = 26

Mehrotra et al. 2014

Eur J Clin Nutr · n = 43

Participants

26 healthy young adults, 25(OH)D at or below 50 nmol/l

43 prediabetic, deficient adults with BMI above 25

Vehicle

Experimental soup — vitamin D2 measured in the delivered product

Chef-prepared cooked entrées — D2 significantly lower after cooking

Dose and schedule

28,000 IU of D2 per week for 5 weeks

600 IU or 4000 IU per day for 16 weeks

Comparator

D2 supplement at the same dose, plus placebo

D3 supplement at matched label dose — a harder benchmark

Result

Serum 25(OH)D rose 3.9 nmol/l per week on mushrooms versus 4.7 nmol/l per week on the D2 supplement — statistically similar. Significantly above placebo by week 2.

Mushroom entrées produced modest or no increase in 25(OH)D2 or total 25(OH)D relative to the D3 control groups over 16 weeks.

The reconciliation: Urbain asked whether vitamin D2 in UV mushrooms is absorbed at all, delivered a large dose in a form that preserved it, and answered yes. Mehrotra asked whether a realistic daily portion of cooked mushrooms corrects deficiency as well as a D3 supplement, and answered no — with cooking losses named as a main reason. Both answers are true, and only the second one describes dinner.

Sources: Urbain P, Singler F, Ihorst G, Biesalski H-K, Bertz H (2011), European Journal of Clinical Nutrition 65(8):965–971. Mehrotra A, Calvo MS, Beelman RB, Levy E, Siuty J, Kalaras MD, Uribarri J (2014), European Journal of Clinical Nutrition 68(10):1154–1160.

The two trials are not contradictory — they are measuring different things. Urbain delivered a large weekly D2 dose in a soup and asked whether it was absorbed. Mehrotra delivered a smaller daily dose in cooked entrées and asked whether it corrected deficiency as well as D3 did. Together they support a specific conclusion: mushroom D2 is genuinely bioavailable, but cooking losses and the lower potency of D2 relative to D3 mean UV mushrooms are a supplement to a vitamin D strategy, not a replacement for one in people who are already deficient.

Vitamin D From Mushrooms

1. Chemistry and content analysiscompleted

   Ergosterol to D2 conversion characterised; content measured across 10 species nationwide (Phillips 2011, Koyyalamudi 2009)

2. Animal bioavailabilitycompleted

   Vitamin D2 from UV-irradiated button mushrooms shown bioavailable in rats (Koyyalamudi 2009)

3. Human randomised trialscurrent

   Bioavailability confirmed in 26 deficient young adults (Urbain 2011); a 16-week trial in 43 prediabetic adults found modest or no benefit versus D3 (Mehrotra 2014)

4. Large trials on clinical endpointsmissing

   No large trial has tested UV mushrooms against fracture, infection or other hard outcomes

5. Pooled synthesismissing

   A 2020 systematic review found vitamin D status the strongest human evidence for A. bisporus, but the trial base is small (Blumfield 2020)

Human evidence exists and is positive on bioavailability, but it rests on two small trials with divergent results. Vitamin D status is the best-supported human health effect of eating mushrooms — and it is still built on a thin trial base.

Phillips 2011; Koyyalamudi 2009; Urbain 2011; Mehrotra 2014; Blumfield 2020

Blumfield and colleagues reached the same conclusion from the top down. Their 2020 systematic review of Agaricus bisporus in humans found beneficial effects across metabolic syndrome, immune function, gastrointestinal health and cancer, but identified improvement in vitamin D status as the strongest human evidence, noting that UVB-exposed mushrooms may raise and maintain serum 25(OH)D to a degree similar to vitamin D supplements. They also called for replication in different populations before findings are adopted into clinical practice.^[10]

Practical implication. Setting mushrooms gill-side up in direct sunlight before cooking increases vitamin D2 content, because the ergosterol sits in the cell walls and the gills present the greatest surface area. Two caveats follow from the trial data: cooking reduces the D2 you end up eating, and mushrooms deliver D2 rather than D3. If you are correcting a diagnosed deficiency, treat mushrooms as a contribution rather than the intervention.

Protein: Higher Than You Think, Once You Account for Water

Mushrooms do not have a reputation as a protein food, and that is partly an artefact of how protein is reported. Fresh mushrooms are roughly 90% water, so fresh-weight protein lands at about 2–4 g per 100 g — the vegetable range. On a dry-weight basis the picture changes.

Effiong and colleagues published the most concrete recent measurement in 2023, a full proximate analysis of Pleurotus ostreatus. On a dry basis they reported 17.06% crude protein, 23.63% crude fibre, 43.42% carbohydrate, 8.22% ash and 1.21% lipid, with moisture of 91.01% in fresh samples and 6.46% in dried. The mineral profile was led by potassium (12.25 mg), iron (9.66 mg) and magnesium (7.00 mg), and the vitamin profile included A, C, E and B vitamins with riboflavin (B2) highest.^[13]

Note that the 91% moisture figure and the 17.06% dry-weight protein figure together explain the fresh-weight number: roughly 1.5 g of protein per 100 g of fresh oyster mushroom. Both numbers describe the same food.

Niego and colleagues reviewed macrofungi as a nutraceutical source in 2021 and described mushrooms as containing high-quality proteins alongside polysaccharides, unsaturated fatty acids, minerals and sterols, with bioactivity supported by in vitro, in vivo and some clinical work.^[8] Gopal and colleagues surveyed the nutritional aspects of Asian mushrooms in 2022 and likewise characterised them as rich reservoirs of proteins, polysaccharides, metabolites, minerals and vitamins, while noting that of roughly 14,000 recorded species only about 2,200 are considered edible and only 650 have been cultivated.^[9] Both are reviews describing protein quality in general terms; neither reports a species-by-species PDCAAS table, and claims that mushroom protein "matches beef" on digestibility-corrected scoring should be treated as unsupported until a specific measurement is cited.

The practical picture: mushrooms are not a protein staple in the way meat or legumes are, because water content keeps per-serving fresh-weight protein low. Per calorie and per dry gram, they compare well with many plant options — and the fibre they bring alongside the protein is unusually high at nearly a quarter of dry weight. For more, see Protein, Fiber, and Micronutrients in Mushrooms: A Comprehensive Analysis.

Fiber, B Vitamins, and Minerals: The Mushroom Micronutrient Stack

Fiber. Mushrooms contain two structurally distinct fibre types. Beta-glucans are the fermentable fraction, associated with immune modulation and cholesterol effects in a large research literature. Chitin is the structural fraction — a tough, insoluble polymer that forms the cell wall and is not digested by human enzymes. A total fibre count includes both, but they behave very differently in the gut. Effiong's 23.63% crude fibre by dry weight in oyster mushrooms captures both fractions together.^[13] For how mushroom fibre compares with other prebiotics, see How Mushroom Fiber Differs from Other Prebiotic Sources, and for the beta-glucan research specifically, What Are Beta-Glucans? The Most Important Compound in Medicinal Mushrooms.

B vitamins. Mushrooms are a recognised source of riboflavin (B2), niacin (B3) and pantothenic acid (B5). The most specific measurement in the sources cited here is Effiong's oyster mushroom analysis, in which riboflavin was the highest of the B vitamins detected.^[13] Gopal's review describes Asian species including shiitake and oyster as vitamin-rich without breaking out per-species B vitamin quantities.^[9] Blumfield's A. bisporus review catalogued its bioactive compounds as ergosterol, ergothioneine, flavonoids, glucans and chitin — it did not assess B vitamins or selenium, and should not be cited for those.^[10]

Minerals. Mushrooms are often described as a strong selenium source. That is plausible for A. bisporus but is not what the oyster mushroom data shows: Effiong found potassium, iron and magnesium as the dominant minerals, and did not report selenium among the leading ones.^[13] Ba's continuous-NHANES paper describes selenium and copper as mushroom minerals of interest in its framing.^[2] Mineral content also depends heavily on growing substrate, which is why figures vary between studies. Species-specific levels are covered in the Mushroom Macronutrients and Micronutrients guide.

Mushrooms and Mental Health: What the Population Studies Actually Found

Two NHANES analyses link mushroom consumption to mental-health outcomes. Both are weaker than their usual summaries suggest, and the details matter.

Ba and colleagues published a depression analysis in the Journal of Affective Disorders in 2021 covering 24,699 US adults from NHANES 2005–2016, with depression defined as PHQ-9 of 10 or more. Mushrooms were eaten by just 5.2% of participants. Compared with the lowest tertile of intake, the middle tertile had substantially lower odds of depression (adjusted OR 0.31, 95% CI 0.16–0.60), based on only 16 cases. The highest tertile showed no difference (adjusted OR 0.91, 95% CI 0.47–1.78), and the trend test was not significant (P-trend = 0.42). The authors state plainly that they did not observe a dose-response relationship.^[11] A finding that appears at moderate intake, disappears at high intake, and rests on 16 cases is a hypothesis, not an effect you can rely on.

The same group published a cognitive analysis in the British Journal of Nutrition in 2022 using NHANES 2011–2014 data on 2,840 adults aged 60 and over. Participants in the highest mushroom intake category (median 13.4 g per 1000 kcal per day) scored higher on the Digit Symbol Substitution Test (β = 3.87, 95% CI 0.30–7.45; P-trend 0.03) and CERAD Word Learning (β = 1.05, 95% CI 0.0003–2.10; P-trend 0.04). Animal Fluency and CERAD Delayed Recall showed no significant association.^[3] Two of four cognitive tests reached significance, one of them barely.

Interpretation

Moderate

These findings are not a treatment indication

Concern

Cross-sectional association studies on depression and cognition are routinely reported as though mushrooms improve mental health. Neither study tested an intervention, and the depression analysis found no dose-response relationship.

What the research says

Read these as signals worth following up in trials, not as a reason to substitute food for care. Depression and cognitive decline are medical conditions with established treatments.

Particularly relevant for: Anyone considering dietary changes in place of, or alongside, treatment for a diagnosed condition

What to do

Talk to a clinician before changing anything about how a diagnosed condition is managed. This article is nutrition education, not medical advice.

Ba DM et al. (2021), J Affect Disord 294:686–692; Ba DM et al. (2022), Br J Nutr 128(11):2241–2248

For the broader evidence on mushrooms and brain health, see Mushrooms and Cognitive Aging: Can They Protect Your Brain?.

Which Mushroom to Eat for Your Nutritional Goal

For vitamin D without UV treatment: maitake, morel and chanterelle measured 5.2–28.1 μg/100 g in the Phillips dataset — far above the common cultivated species.^[6] If you want vitamin D from the mushroom aisle without relying on treatment, these are the species.

For vitamin D from common species: look for "UV-treated" on the label. UV-treated portabella reached 3.4–20.9 μg/100 g.^[6] Home sun exposure gill-side up also works, with the caveat that cooking reduces what survives to the plate.^[16]

For ergothioneine: the honest answer is that reliable per-species rankings are thinner than the internet suggests. The strongest single measurement here is Pleurotus citrinopileatus (golden oyster) at 822 μg/g dry weight.^[18] Kalaras found a 48-fold spread across species and more ergothioneine in caps than stems, and more in later cropping flushes.^[4] Specialty species generally outperform white button.^[17]

For protein and fibre together: oyster mushrooms are the best-characterised, at 17.06% protein and 23.63% fibre by dry weight.^[13]

For lowest calories: white button and portabella sit around 22 kcal per 100 g fresh, the lowest in the table; maitake and morel are close behind at about 31 kcal.

For variety: the population studies that found mortality and cognitive associations measured general mushroom intake, not any single species. Nothing in that evidence supports optimising for one mushroom. Rotating between A. bisporus, an oyster or shiitake, and a naturally high-vitamin-D species like maitake covers more ground than any single choice — and, per Jung's Korean cohort, the benefit appeared at one to three servings per week rather than at the highest intakes.^[14]

For a nutrient-density comparison across species, see Why Mushrooms Are the Most Nutrient-Dense Low-Calorie Food.

The Bottom Line

Mushrooms occupy a nutritional position no other food group holds: the richest common dietary source of ergothioneine, one of the very few non-fortified foods that can supply meaningful vitamin D, and a food that large prospective cohorts associate with lower all-cause mortality. The species data shows the vitamin D gap is the largest real difference between mushrooms — morel, chanterelle and maitake measured up to a hundred times the level in white button. The mortality evidence is consistent in direction across US and Korean cohorts but remains observational, all-cause rather than cause-specific, and strongest at moderate rather than maximal intake. Several widely repeated figures in mushroom nutrition writing — a 628 μg/g porcini ergothioneine value, a human clinical trial that was actually conducted in rats, a 16% depression reduction — do not survive a check against their source papers, and this guide gives the measured values in their place.

Frequently Asked Questions

Which mushroom has the most protein?

Oyster mushrooms are the best-measured: Effiong et al. (2023) reported 17.06% crude protein by dry weight for Pleurotus ostreatus, alongside 23.63% crude fibre. Because fresh mushrooms are around 91% water, that corresponds to roughly 1.5g per 100g fresh. Across species, fresh-weight protein typically runs 2-4g per 100g. Reviews describe mushroom protein as high quality, but claims that it matches beef on digestibility-corrected scoring are not backed by a specific published measurement, so treat them cautiously.

Are mushrooms high in vitamin D?

It depends entirely on the species and how it was grown. Phillips et al. (2011) measured only 0.1-0.3 μg per 100g in white button, crimini, portabella and enoki, but 5.2-28.1 μg per 100g in morel, chanterelle and maitake, and 3.4-20.9 μg per 100g in UV-treated portabella. Urbain et al. (2011) showed in a randomised trial that UV-B mushrooms raised serum 25(OH)D at a rate similar to a D2 supplement in 26 deficient adults. A later trial in prediabetic adults found only modest or no increase, largely because cooking degraded the vitamin D2. Look for "UV-treated" on labels, and treat mushrooms as a contribution to vitamin D intake rather than a replacement for supplementation if you are deficient.

What vitamins are in mushrooms?

Mushrooms supply B vitamins — riboflavin (B2) was the highest B vitamin in the oyster mushroom analysis by Effiong et al. (2023), which also detected vitamins A, C and E. Vitamin D2 is present in meaningful amounts only in certain species or after UV exposure. Mushrooms also contain ergothioneine, a sulfur-containing compound for which they are the richest common dietary source, though Ey et al. (2007) also detected it in kidney, liver, beans and oat bran. Ergothioneine is not officially classified as a vitamin. B12 analogues occur in some species, but bioavailability is contested and mushrooms are not a reliable B12 source.

How many calories are in mushrooms?

Fresh mushrooms run roughly 20-38 calories per 100g depending on species, using USDA reference values. White button, crimini and portabella sit at the low end (around 22 kcal per 100g); enoki and chanterelle are higher (around 37-38 kcal per 100g). The low calorie count alongside fibre, B vitamins and ergothioneine makes mushrooms nutrient-dense per calorie. In NHANES III, modelling one daily serving of mushrooms in place of processed or red meat was associated with a 35% lower all-cause mortality risk (HR 0.65) — though that is an observational substitution model, not a tested intervention.

Which mushroom is the healthiest to eat?

No single species is uniformly best, and the population evidence does not support choosing one. The NHANES and Korean cohort studies that found mortality and cognitive associations measured general mushroom intake, not specific species. On measurable nutrients: maitake, morel and chanterelle lead on naturally occurring vitamin D; oyster mushrooms are the best-characterised for protein and fibre; golden oyster recorded the highest verified ergothioneine value (822 μg/g dry weight) among species tested by Tsiantas et al. (2021). In the Korean cohort, the lower mortality risk appeared at one to three servings per week rather than at the highest intake, so variety and regularity look more important than picking a single "best" mushroom.

Sources & References

1. 1RTHM-00673·Ba, Djibril M et al. (2021). “Association of mushroom consumption with all-cause and cause-specific mortality among American adults: prospective cohort study findings from NHANES III..” Nutrition journal.Study breakdown →PubMed →↩
2. 2RTHM-00674·Ba, Djibril M et al. (2021). “Prospective study of dietary mushroom intake and risk of mortality: results from continuous National Health and Nutrition Examination Survey (NHANES) 2003-2014 and a meta-analysis..” Nutrition journal.Study breakdown →PubMed →↩
3. 3RTHM-00741·Ba, Djibril M et al. (2022). “Mushroom intake and cognitive performance among US older adults: the National Health and Nutrition Examination Survey, 2011-2014..” The British journal of nutrition.Study breakdown →PubMed →↩
4. 4RTHM-00476·Kalaras, Michael D et al. (2017). “Mushrooms: A rich source of the antioxidants ergothioneine and glutathione..” Food chemistry.Study breakdown →PubMed →↩
5. 5RTHM-00270·Weigand-Heller, AuBrei J et al. (2012). “The bioavailability of ergothioneine from mushrooms (Agaricus bisporus) and the acute effects on antioxidant capacity and biomarkers of inflammation..” Preventive medicine.Study breakdown →PubMed →↩
6. 6RTHM-00230·Phillips, Katherine M et al. (2011). “Vitamin D and sterol composition of 10 types of mushrooms from retail suppliers in the United States..” Journal of agricultural and food chemistry.Study breakdown →PubMed →↩
7. 7RTHM-00159·Koyyalamudi, Sundar Rao et al. (2009). “Vitamin D2 formation and bioavailability from Agaricus bisporus button mushrooms treated with ultraviolet irradiation..” Journal of agricultural and food chemistry.Study breakdown →PubMed →↩
8. 8RTHM-01414·Niego, Allen Grace et al. (2021). “Macrofungi as a Nutraceutical Source: Promising Bioactive Compounds and Market Value..” Journal of fungi (Basel.Study breakdown →PubMed →↩
9. 9RTHM-01525·Gopal, Judy et al. (2022). “Scrutinizing the Nutritional Aspects of Asian Mushrooms, Its Commercialization and Scope for Value-Added Products..” Nutrients.Study breakdown →PubMed →↩
10. 10RTHM-00610·Blumfield, Michelle et al. (2020). “Examining the health effects and bioactive components in Agaricus bisporus mushrooms: a scoping review..” The Journal of nutritional biochemistry.Study breakdown →PubMed →↩
11. 11RTHM-00672·Ba, Djibril M et al. (2021). “Mushroom intake and depression: A population-based study using data from the US National Health and Nutrition Examination Survey (NHANES), 2005-2016..” Journal of affective disorders.Study breakdown →PubMed →↩
12. 12RTHM-00696·Lam-Sidun, Daniel et al. (2021). “Mushroom-Derived Medicine? Preclinical Studies Suggest Potential Benefits of Ergothioneine for Cardiometabolic Health..” International journal of molecular sciences.Study breakdown →PubMed →↩
13. 13RTHM-00823·Effiong, Magdalene Eno et al. (2023). “Assessing the nutritional quality of Pleurotus ostreatus (oyster mushroom)..” Frontiers in nutrition.Study breakdown →PubMed →↩
14. 14RTHM-00833·Jung, Hyein et al. (2023). “Edible mushroom intake and risk of all-cause and cause-specific mortality: results from the Korean Genome and Epidemiology Study (KoGES) Cohort..” Food & function.Study breakdown →PubMed →↩
15. 15RTHM-00237·Urbain, P et al. (2011). “Bioavailability of vitamin D₂ from UV-B-irradiated button mushrooms in healthy adults deficient in serum 25-hydroxyvitamin D: a randomized controlled trial..” European journal of clinical nutrition.Study breakdown →PubMed →↩
16. 16RTHM-00340·Mehrotra, A et al. (2014). “Bioavailability of vitamin D2 from enriched mushrooms in prediabetic adults: a randomized controlled trial..” European journal of clinical nutrition.Study breakdown →PubMed →↩
17. 17RTHM-00213·Ey, Janine et al. (2007). “Dietary sources and antioxidant effects of ergothioneine..” Journal of agricultural and food chemistry.Study breakdown →PubMed →↩
18. 18RTHM-00725·Tsiantas, Konstantinos et al. (2021). “On the Identification and Quantification of Ergothioneine and Lovastatin in Various Mushroom Species: Assets and Challenges of Different Analytical Approaches..” Molecules (Basel.Study breakdown →PubMed →↩