Cordyceps made international headlines after Chinese runners decimated two world records in 1993. According to their coach, the secret to their remarkable athletic performance was caterpillar fungi.

Although the Chinese coach was later found to be giving these athletes illegal performance-enhancing drugs, the fungus itself is quite real. Cordyceps sinensis is the scientific name of this special mushroom.

The fungus regained the spotlight 20 years later after critically acclaimed video game “The Last of Us” featured Cordyceps as a zombie-generating fungus. The video game drew inspiration from how various species of Cordyceps can act like body snatchers to insects. These parasitic fungi invade the host and replace their body tissue.

There are more than 350 Cordyceps-related species of fungus and insect hosts. The most well-known is the “ant zombie” fungus called Ophiocordyceps unilateralis, which releases behavior-controlling chemicals. O. unilateralis stimulates ants to bite down on a leaf with a “death grip.” When the ant dies, the fungus grows and emerges like a stalk of antlers from behind the ant’s head, ready to spread its spores.

The Cordyceps species that takes over caterpillar bodies is much less aggressive. While this fungus has evolved to infect tarantulas, there’s no evidence that Cordyceps can infect humans.

People have used C. sinensis for medicinal purposes since the 15th century. This fungus is also sometimes referred as:

  • yartsa gunbu, Tibetan for “summer grass, winter worm”
  • dong chong xia cao, Chinese for “worm-grass”
  • caterpillar mushroom
  • Ophiocordycipitaceae
  • Hirsutella sinensis

C. sinensis is available in the United States as a nutritional supplement in pill form and as a tonic. Read on to discover why people are fans of C. sinensis and its health benefits.

Herbs and supplements aren’t regulated by the U.S. Food and Drug Administration (FDA). It’s possible to get a product that’s contaminated or of poor quality, especially for C. sinensis. Buy your C. sinensis from a reputable source. Some sellers may pass off fake mushrooms as the real kind, which can be expensive.

C. sinensis is both a fungus and a caterpillar. It grows out of the ground from caterpillar bodies in the high altitudes of the Himalayas and the Tibetan plateau. Uncultured fungus doesn’t have the same medicinal effect.

Cultured C. sinensis starts as a spore in the winter. The spore lands on a particular moth caterpillar and enters the caterpillar’s body. The caterpillar buries itself into the soil before it dies. When summer comes around, the fungus grows like a plant from the caterpillar’s head with the appearance of a thin, orange finger.

Working in the cool mountains and chatting with friends makes harvesting C. sinensis a pretty relaxing job. And it’s highly profitable. People in Tibet harvest C. sinensis as a source of income because it can’t be commercially cultivated. Finding these tiny mushrooms takes a lot of skill, concentration, and practice.

The cultured form of the fungus has more than 20 bioactive ingredients, such as sugar molecules with antioxidant properties. These ingredients potentially stimulate cells and specific chemicals in the body, including the immune system.

C. sinensis is also thought to increase the production of adenosine triphosphate (ATP), which is essential for delivering energy to the muscles. This may improve the way your body uses oxygen.

There’s no consistent evidence that C. sinensis can boost exercise performance. But there is scientific evidence suggesting that C. sinensis can:

  • boost your body’s immune system
  • have an antihyperglycemic effect (as seen in animals with diabetes)
  • help with fatigue (it prolonged swimming time in mice by 20 and 24 minutes)
  • reverse liver fibrosis (as seen in studies involving rats and mice)

In a study involving rats, C. sinensis was found to help with antiaging due to these properties:

  • antioxidant
  • anti-inflammatory
  • antitumor
  • antihyperglycemic (promotes low blood sugar)
  • anti-apoptosis (stops cell death)
  • immunomodulatory (regulates the immune system)
  • nephroprotective (kidney protective)
  • hepatoprotective (liver protective)

More research is needed to confirm the effect of C. sinensis on human health.

Always talk to your doctor before taking a supplement for any condition.

Reduces inflammation

C. sinensis may have anti-inflammatory properties. Research shows that the fungus is effective at reducing inflammation on a cellular level. But it has yet to be tested on humans or animals.

Cordycepin may also be a good anti-inflammatory alternative for people with asthma, according to the University of Nottingham. Cordycepin is a drug found in this mushroom. It’s shown to reduce inflammation in the airway.

Protects the heart

C. sinensis may offer heart-health benefits, including the ability to treat arrhythmia. A 2014 study saw C. sinensis significantly reduce liver and heart injuries in rats.

This study shows that C. sinensis has the potential to treat heart disease. In fact, it’s approved in China to treat arrhythmia. It’s thought that the adenosine in C. sinensis handles this effect. Adenosine is a naturally occurring substance that helps break down ATP.

Slows kidney disease

Traditionally, people believed that consuming C. sinensis strengthened the kidneys. This may be due to the mushroom’s ability to increase hydroxyl-corticosteroid and ketosteroid levels in the body.

In a 2011 study, researchers at Zhejiang University found that C. sinensis may inhibit renal fibrosis in rats. Renal fibrosis is a condition that occurs in the later stages of kidney disease.

Slows tumor growth

Some studies on animals suggest that C. sinensis may slow the growth of tumors from certain types of cancer. One theory is that it can stimulate the immune system to fight cancer.

Research indicates the fungus may have antitumor effects on cells. This is from both natural and cultured C. sinensis. This cytotoxic effect worked on several types of tumor cells, including melanoma, prostate tumors, and Lewis lung carcinoma. Interestingly, C. sinensis didn’t stop the cell life cycle in normal cells.

Revs up libido

Due to claims about its potential as an aphrodisiac, C. sinensis has long been used to increase libido.

Several studies show that C. sinensis increases testosterone. A 2009 study suggested that C. sinensis may help penile erection and mount latency in rats. A 2007 study found that the supplement resulted in improved sperm volume and serum testosterone in subfertile boars.

But there’s no credible human trials to show that the fungus enhances libido or sexual performance in people. A 2016 review confirmed these findings.

Though studies are still determining the efficiency of these uses, common C. sinensis applications include:

  • boosting athletic performance, including increasing stamina and energy
  • complementary treatment for chemotherapy, to improve treatment response and quality of life
  • boosting sex drive
  • reducing asthma symptoms, though there’s evidence that C. sinensis isn’t effective

The price of C. sinensis is dear — $20,000 per kilogram, according to a 2016 BBC story. As well, there may be products on the market with other species of Cordyceps rather than C. sinensis. Be sure to buy C. sinensis from a reputable source, as there are no benefits from the other species.

So far, C. sinensis has been commonly linked to the following side effects:

  • gastrointestinal upset or discomfort
  • diarrhea
  • nausea
  • dry mouth

Clinical trials are still underway to determine the effects. C. sinensis can also have interactions with other substances or drugs, including:

  • caffeine
  • cyclophosphamide, such as Cytoxan
  • immunosuppressants
  • anticoagulants

You shouldn’t take this supplement if you have an autoimmune disease. This includes conditions like multiple sclerosis, lupus, or rheumatoid arthritis. C. sinensis could aggravate your symptoms.

You should also avoid this supplement if you have any bleeding disorders.

If you have any of these conditions or liver problems, this supplement may not be appropriate to take, so speak with your healthcare provider.

The limited supply of C. sinensis makes researching the benefits difficult. Many studies were unable to artificially infect caterpillars with this fungus.

Some research does support the health benefit claims on a cellular level and in animals. But it doesn’t have a direct effect on exercise. Research has shown that there’s no significant improvement in exercise and oxygen intake.

Always talk to your doctor before taking any supplements or herbal medications. Herbs and supplements aren’t monitored by the FDA. Buy from a reputable source to avoid problems with quality and purity.