If a headline about tamogitake just caught your eye, here is the short version. Tamogitake is a mushroom, and the study behind the headline gave its powder to rats and diabetes-model mice. The paper, published 13 November 2026 in Food, Nutrition and Health, reports that the powder reduced liver cholesterol and liver triacylglycerol (a type of fat) in both species. The powder made up 5% of the animals’ feed, and the report says the authors could not put that effect down to ergothioneine alone. Below you’ll find what was in the powder, what the study measured, and what it does and does not tell you about your own cholesterol or weight.
What is tamogitake?
Tamogitake is the name used for this mushroom in the study and in news coverage of it. The paper gives its species name as Pleurotus cornucopiae var. citrinopileatus. If you searched for “golden oyster mushroom,” use that species name to find the paper, because it is the name the paper uses. The researchers tested a freeze-dried powder made from the mushroom.
What was in the tamogitake powder?
The Bioengineer.org report on tamogitake, dated 13 November 2026, lists the composition of the freeze-dried powder as follows.
| Component | Amount in the powder |
|---|---|
| Carbohydrate | 49% |
| Crude protein | 31.8% |
| Lipid | 3.0% |
| Moisture | 10.3% |
| Ash | 5.9% |
| Total dietary fiber | 38.9% (37.1% insoluble, 1.8% soluble) |
| Beta-glucan | 14.1% |
| Ergothioneine | 0.61% |
Beta-glucan is a term you will see on many mushroom labels. Our guide to real mushrooms lion’s mane explains how beta-glucans are described on mushroom products.
Quick facts about the tamogitake study
These facts are as of 2026-11-13.
| Fact | Detail |
|---|---|
| Species named in the paper | Pleurotus cornucopiae var. citrinopileatus (tamogitake) |
| Journal | Food, Nutrition and Health (Springer Nature), vol. 3, article 43 |
| Published | 13 November 2026 |
| News report | Bioengineer.org, dated 13 November 2026, credits Scienmag as the source |
| Animals studied | Male Sprague-Dawley rats (4 weeks old) and male KK-Ay mice (3 weeks old), 6 per group |
| People in the study | None. The report says the study is rodent-only. |
| Powder amount | 5% of the animals’ diet |
| Length of the study | 4 weeks in rats; 52 days in mice |
| Funding | “There was no funding for this study.” (the paper) |
| Powder supplier | Athree Corporation, which the paper says supplied the powder |
| Author affiliations | One author is affiliated with Athree Corporation and another with Tomuso Corporation |
What did the rat and mouse study do?
The Food, Nutrition and Health paper describes two experiments. The report summarizes them this way.
- Rats: Male Sprague-Dawley rats, 4 weeks old, 6 per group, in four groups. The diets were AIN-76-based. Some had 5% tamogitake powder, some had 0.5% cholesterol added, and the cholesterol diet also contained 0.125% cholic acid. The study ran for 4 weeks.
- Mice: Male KK-Ay mice, 3 weeks old, 6 per group. All diets contained 0.5% cholesterol. One group had a control diet, one had 5% tamogitake powder, and one had 0.05% pure ergothioneine, which the paper says matched the ergothioneine in the 5% powder. The study ran for 52 days, until hyperglycemia developed.
What did the study find?
The paper reports the following changes in the two species.
| Measure | Rats | Mice |
|---|---|---|
| Liver weight | Reduced | Reduced |
| Liver total cholesterol | Reduced, with or without dietary cholesterol | Reduced |
| Liver triacylglycerol | Reduced, with or without dietary cholesterol | Reduced |
| Body-weight gain and white fat mass | Did not change | Body-weight gain per day was lowered |
| Serum insulin | Lower with Tamogitake | Did not differ among groups |
| Serum lipids | Not changed by the mushroom; the cholesterol diet raised them | Did not differ among groups |
In rats, free cholesterol in the liver fell, while cholesteryl ester did not. In mice, serum leptin was lowered, fecal weight rose, and fecal cholesterol and free fatty acid excretion “tended” to rise. Bile acid excretion did not change.
Does ergothioneine explain the liver effect?
Ergothioneine was one of the things the researchers looked at. In the mice, pure ergothioneine, matched to the powder’s ergothioneine content, did not change liver fats. The report says the authors concluded that the powder’s effect could not be put down to ergothioneine alone.
Ergothioneine has also been studied in people, but in a different product. Nutraceuticals World reported on August 27, 2025, on a 16-week study of 147 adults aged 55 to 79 with subjective memory complaints. Participants took a placebo or a supplement with 10 mg or 25 mg of an ergothioneine ingredient marketed by Blue California as ErgoActive. The outlet notes that the company’s VP of science and innovation co-authored the study. The Nutraceuticals World ergothioneine trial report says subjective prospective memory and sleep initiation appeared to improve in a dose-dependent manner, and that the supplement was safe and well-tolerated.
What does this mean for cholesterol, weight and belly fat?
If you wondered whether oyster-type mushrooms help cholesterol, this study tested only tamogitake powder, in animals. In the rats and mice, liver cholesterol fell. Serum cholesterol in the rats was not changed by the mushroom, and the cholesterol diet is what raised it.
For weight, the paper measured body-weight gain and, in rats, white fat mass. In rats, white fat mass did not change. In mice, body-weight gain per day was lower.
The authors propose one explanation: the insoluble fiber in the powder may promote fecal loss of lipids and expansion of the cecum. The paper calls for future work on intestinal cholesterol transporters and gut microbiota.
What does the NIDDK say about diet and fatty liver?
The NIDDK diet guidance for fatty liver, last reviewed April 2021, says a healthy diet, limited portion sizes and a healthy weight may help prevent fatty liver disease in people who do not have it. Its diet advice includes:
- Limiting fats, and replacing saturated and trans fats with unsaturated fats, especially omega-3 fatty acids.
- Eating more low-glycemic-index foods such as most fruits, vegetables and whole grains.
- Avoiding foods and drinks high in simple sugars, especially fructose.
- Minimizing alcohol, which can further damage the liver.
That guidance is not about tamogitake, and the NIDDK does not link it to this study.
Common mix-ups to avoid
- Two different ergothioneine studies. The rat and mouse paper tested tamogitake powder. The 16-week human trial tested an ergothioneine ingredient from a different company.
- Feed share, not a serving. The 5% figure is a share of the animals’ feed. It is not a serving size for people.
- Species name. Search for Pleurotus cornucopiae var. citrinopileatus to find the primary paper.
- Blends are a separate question. If you are comparing several mushrooms in one product, see mushroom complex benefits for how blends are studied.
Key dates
| Date | What happened |
|---|---|
| 12 May 2026 | The paper was received. |
| 9 August 2026 | The paper was revised. |
| 14 August 2026 | The paper was accepted. |
| 13 November 2026 | The paper was published, and Bioengineer.org dated its report the same day. |
Who should read this study closely?
A result in rats and mice is not a result in people. The study gives no human dose, and the 5% figure describes the animals’ feed only.
If you are asking because of your liver, your cholesterol or a medicine you take, your doctor or pharmacist is the person to ask before you change anything.
Questions to settle before you act
- Did people take part in the study? No. The report says it was rodent-only.
- Who supplied the powder? The paper says Athree Corporation supplied it, and one author is affiliated with that company.
- Where can you read the full paper? At the Food, Nutrition and Health article linked above, under DOI 10.1007/s44403-026-00089-6.
By NewEasternHealth.com Research Team