Oyster mushroom has not been shown to treat cancer in humans.
Oyster mushroom is an edible fungus. It is used in traditional medicine to treat infections, diabetes, cancer, and to lower cholesterol. Laboratory experiments and studies done in mice have shown that oyster mushrooms have antitumor, antifungal, and cholesterol-lowering properties. A study done in children with upper respiratory tract infections showed that oyster mushroom has anti-allergic effects. It was also shown to lower glucose levels and increase insulin levels in patients with type 2 diabetes, but more studies are needed to confirm such effects.
Purported Uses
Antitumor
Oyster mushrooms increased survival in tumor-bearing mice but no such studies have been done in humans.
Antifungal
One laboratory study showed that oyster mushroom has antifungal activity.
High fat levels in the blood
Studies done in mice suggest that oyster mushroom lowers the level of fats or lipids in the blood. However, a clinical trial did not find such benefits in HIV patients who had high cholesterol levels caused by antiretroviral treatment.
Diabetes
Studies in mice and humans suggest that oyster mushroom may lower blood sugar levels and increase insulin levels. More studies are needed to confirm these effects.
Do Not Take If
You are allergic to mushrooms.
Side Effects
Case reports
Occupational asthma, widespread lung inflammation: Following exposure to oyster mushroom spores.
Oyster mushroom is an edible fungus found widely in North America and Europe. It is used in traditional medicine to treat infections, hyperlipidemia, diabetes, and cancer.
In vitro experiments and studies done in mice have shown that oyster mushroom has antitumor (1)(7)(8)(9)(12)(13), immunomodulatory (10)(11), antifungal (2), lipid-lowering, and hypoglycemic (3)(6) properties. Beneficial effects are due to constituents such as polysaccharides, lectins, and peptides.
In a study of HIV patients with antiretroviral treatment-induced hypercholesterolemia, oyster mushroom was not effective in lowering non-HDL cholesterol (5). However pleuran, a beta-glucan isolated from oyster mushroom, demonstrated anti-allergic effects in children with respiratory tract infections (17). In type 2 diabetic patients, an oyster mushroom preparation reduced postprandial serum glucose levels and increased serum insulin levels (19).
Food Sources
Oyster mushroom is an edible fungus, available both in fresh and dried forms. The whole mushroom is often used in soups and sauces.
Purported Uses
Cancer treatment
Diabetes
Hyperlipidemia
Infections
Mechanism of Action
Pleurostrin, a peptide derived from the fruiting bodies of oyster mushroom, exhibited antifungal properties (2). Mevinolin, another compound, decreased cholesterol biosynthesis by inhibiting HMG CoA reductase, which is the rate-limiting enzyme in cholesterol biosynthesis (3). Ostreolysin, a cytolytic protein isolated from oyster mushroom, caused bradycardia, myocardial ischemia and ventricular extrasystoles following intravenous injection in mice (14). Suggested hypoglycemic mechanisms include increased glucokinase activity and insulin secretion, which increases glucose utilization by peripheral tissues, inhibits glycogen synthase kinase, and promotes glycogen synthesis (19).
A lectin isolated from the fruiting bodies of oyster mushroom demonstrated antitumor activity in mice bearing sarcoma and hepatoma (1). Another study found that the development of precancerous aberrant crypt foci (ACF) was significantly reduced in mice that were fed a diet containing 10% pleuran, a beta-glucan isolated from oyster mushroom (4). RNase Po1, a guanylic acid-specific ribonuclease (a RNase T1 family RNase) from oyster mushroom has been shown to induce apoptosis in tumor cells (18).
Contraindications
Hypersensitivity to oyster mushrooms.
Adverse Reactions
Case reports
Occupational asthmaandallergic alveolitis: Following exposure to oyster mushroom spores (15)(16).
