Turkey tail (Coriolus versicolor) is a mushroom. It contains polysaccharide peptide (PSP) and polysaccharide krestin (PSK), which are used as medicine.

Turkey tail mushroom grows on stumps and the decomposing wood of trees. The PSP and PSK in turkey tail mushroom might help slow cancer growth and boost the immune system.

People use turkey tail mushroom to improve response to cancer medicines and radiation. It is also used for muscle strength, fatigue, UTIs, and many other conditions

Antioxidants are compounds that help inhibit or reduce damage caused by oxidative stress.

Oxidative stress results from an imbalance between antioxidants and unstable molecules known as free radicals. This can result in cellular damage and chronic inflammation (1Trusted Source).

This imbalance has also been linked to an increased risk of developing health conditions, such as certain cancers and heart disease (2Trusted Source, 3Trusted Source).

Thankfully, eating foods rich in antioxidants or supplementing with these powerful compounds can reduce oxidative stress and inflammation.

Turkey tail contains an impressive array of antioxidants, including phenols and flavonoids (4Trusted Source).

In fact, one study detected over 35 different phenolic compounds in a sample of turkey tail mushroom extract, along with the flavonoid antioxidants quercetin and baicalein (5Trusted Source).

Phenol and flavonoid antioxidants promote immune system health by reducing inflammation and stimulating the release of protective compounds (6Trusted Source).

For example, quercetin has been shown to promote the release of immunoprotected proteins like interferon-y, while inhibiting the release of the pro-inflammatory enzymes cyclooxygenase (COX) and lipoxygenase (LOX) (7Trusted Source).

Turkey tail contains a wide variety of phenol and flavonoid antioxidants which help
promote your immune system health by reducing inflammation and stimulating the
release of protective compounds.

Polysaccharopeptides are protein-bound polysaccharides (carbohydrates) that are found in, for example, turkey tail mushroom extract.

Krestin (PSK) and Polysaccharide Peptide (PSP) are two types of polysaccharopeptides found in turkey tails (8Trusted Source).

Both PSK and PSP possess powerful immune-boosting properties. They promote immune response by both activating and inhibiting specific types of immune cells and by suppressing inflammation.

For instance, test-tube studies have demonstrated that PSP increases monocytes, which are types of white blood cells that fight infection and boost immunity (9Trusted Source).

PSK stimulates dendritic cells that promote immunity to toxins and regulate the immune response. In addition, PSK activates specialized white blood cells called macrophages, which protect your body against harmful substances like certain bacteria (10Trusted Source).

Due to their ability to naturally strengthen the immune system, PSP and PSK are commonly used as anticancer agents in conjunction with surgery, chemotherapy and/or radiation in countries like Japan and China (11Trusted Source).

PSK and PSP are powerful polysaccharopeptides found in turkey tail mushrooms that may
strengthen the health of your immune system.

Research has demonstrated that turkey tail mushrooms may have antitumor properties, thought to be related to its immune-boosting effects.

One test-tube study found that PSK, the polysaccharopeptide found in turkey tail mushrooms, inhibited the growth and spread of human colon cancer cells (12Trusted Source).

What’s more, a certain type of polysaccharide found in turkey tail mushrooms called Coriolus versicolor glucan (CVG) may suppress certain tumors.

A study in tumor-bearing mice found that treatment with 45.5 and 90.9 mg per pound (100 and 200 mg per kg) of body weight of CVG extracted from turkey tail mushrooms daily significantly reduced tumor size (13Trusted Source).

Researchers attributed this development to enhanced immune response (13Trusted Source).

Another study demonstrated that daily treatment with 45.5 mg per pound (100 mg per kg) of body weight of turkey tail mushroom extract significantly slowed the spread of cancer cells and improved survival times in dogs with highly aggressive cancer (hemangiosarcoma) (14Trusted Source).

However, the most impressive evidence regarding the anticancer benefits of turkey tail mushroom is when it’s used in combination with more traditional treatments, such as chemotherapy and radiation (15Trusted Source, 16Trusted Source, 17Trusted Source).

Turkey tail mushrooms contain components such as PSK and CVG that may suppress the
growth of certain types of cancers.

Due to the many beneficial compounds it contains, turkey tail is commonly used in tandem with traditional treatments like chemotherapy as a natural way to fight certain cancers.

A review of 13 studies found that patients given 1–3.6 grams of turkey tail mushroom per day along with conventional treatment had a significant survival advantage.

The study showed that people with breast cancer, gastric cancer or colorectal cancer treated with turkey tail and chemotherapy experienced a 9% reduction in 5-year mortality compared to chemotherapy alone (15Trusted Source).

Another review of 8 studies in over 8,000 people with stomach cancers demonstrated that those who were given chemotherapy along with PSK lived longer after surgery than individuals given chemotherapy without PSK (16Trusted Source).

A study in 11 women with breast cancer found that those who were given 6–9 grams of turkey tail powder per day following radiation therapy experienced an increase in cancer-fighting cells in the immune system, such as natural killer cells and lymphocytes (17Trusted Source).

May Enhance Gut Health

Keeping a healthy balance of beneficial bacteria in your gut is critical for maintaining a strong immune system.

Your gut bacteria interact with immune cells and directly impact your immune response (18Trusted Source).

Turkey tail contains prebiotics, which help nourish these helpful bacteria.

An 8-week study in 24 healthy people found that consuming 3,600 mg of PSP extracted from turkey tail mushrooms per day led to beneficial changes in gut bacteria and suppressed the growth of the possibly problematic E. coli and Shigella bacteria (19Trusted Source).

A test-tube study found that turkey tail extract modified gut bacteria composition by increasing populations of beneficial bacteria like Bifidobacterium and Lactobacillus while reducing potentially harmful bacteria, such as Clostridium and Staphylococcus (20Trusted Source).

Having healthy levels of Lactobacillus and Bifidobacterium bacteria has been linked to improved intestinal symptoms like diarrhea, enhanced immune system, reduced cholesterol levels, lower risks of certain cancers and improved digestion (21Trusted Source).

Turkey tail mushroom may positively impact gut bacterial balance by enhancing the
growth of beneficial bacteria while suppressing harmful species.

people with HPV found that 88% of participants treated with turkey tail
experienced positive results, such as clearance of HPV, compared to just
5% of the control group (22Trusted Source).

Turkey tail is loaded with antioxidants, such as flavonoids and phenols that may reduce inflammation. Inflammation has
been linked to chronic diseases, such as diabetes and certain cancers (23Trusted Source).

 In a test-tube study, turkey tail extract inhibited the growth of Staphylococcus aureus and Salmonella enterica, bacteria that can
cause illness and infection (24Trusted Source).

A mouse study showed that turkey tail extract improved exercise performance and reduced
fatigue. Plus, the mice treated with turkey
tail experienced lower blood sugar levels at rest and post-exercise (25Trusted Source).

 A study in rats with type 2 diabetes demonstrated that turkey tail extract significantly reduced blood sugar levels and improved insulin resistance (26Trusted Source).