A mushroom that grows inside a caterpillar and looks like a blade of grass: Cordyceps is one of the most unusual organisms found on the Tibetan Plateau. The people there call it Yartsa Gunbu, “summer grass, winter worm,” and collecting it remains an important source of income for many families.
In this guide, you'll learn how the caterpillar fungus lives, why it is one of the world's most expensive natural products, what it contains, and what to look for in Cordyceps capsules.
What is Cordyceps? Meet the caterpillar fungus
Most medicinal mushrooms, such as Reishi, lion's mane, Chaga, or Shiitake, grow on wood. Cordyceps is different: It is an entomopathogenic fungus, meaning it infects insects. On the Tibetan Plateau, at elevations between 3,000 and 5,000 meters, it grows inside the larvae of ghost moths, a species of moth native to the region. The fungal network spreads through the larva underground, then in spring it sends a slender, club-shaped fruiting body up to the surface.
That's where its German name comes from: caterpillar fungus. Since 2007, its botanical name has been Ophiocordyceps sinensis: genetic studies showed that the old genus Cordyceps included several unrelated groups. The older name Cordyceps sinensis is still used commercially.
Tradition and history
Records of the caterpillar fungus appear in traditional Tibetan medicine from the 15th century onward, and in traditional Chinese medicine from the 17th century onward. It was considered a tonic and was often prepared with other ingredients in soups or teas.
Because the fungus grows only at high elevations and has to be painstakingly dug out of the ground by hand, wild-harvested specimens are extremely expensive and sold by weight. In parts of Tibet and Nepal, collecting it accounts for a large share of entire villages' annual income, putting considerable pressure on stocks. This long tradition is culturally fascinating, but it is not scientific evidence of an effect.
From wild harvesting to controlled production
Wild harvesting is not a viable option for supplements in any significant quantity, either in terms of price or supply. The raw materials therefore come from controlled production, usually through fermentation: The fungal network grows in tanks on a nutrient medium, without any caterpillars.
When comparing products, check which species they contain. Alongside Ophiocordyceps sinensis, Cordyceps militaris is often sold. This is a separate species that readily forms fruiting bodies on a substrate, making it suitable for large-scale cultivation. Both are commonly called Cordyceps, but they are not the same.
Ingredients: what's in caterpillar fungus
Caterpillar fungus has been studied for its proteins, fats, carbohydrates, polysaccharides, sterols such as ergosterol, nucleosides, and minerals. Two substances are a particular focus of research:
Cordycepin
Cordycepin is a nucleoside that is chemically similar to the body's own adenosine. It was first isolated from Cordyceps militaris in the 1950s. Cordyceps militaris contains significantly more of it than Ophiocordyceps sinensis.
Polysaccharides
Like other fungi, Cordyceps produces a variety of complex carbohydrates, including beta-glucans. Some are found in the chitin cell wall, which humans cannot break down. That's why mushrooms used in supplements are usually extracted with hot water.
What research is investigating
There are numerous studies on Cordyceps and cordycepin. By far the largest share comes from laboratory work, cell cultures, and animal studies, often using isolated cordycepin in quantities that have nothing to do with a capsule. Human studies are rare, small, and vary in quality. These findings do not establish an effect in humans and are no substitute for medical treatment.
How to spot good Cordyceps capsules
- Species listed: Does the label say Cordyceps sinensis (Ophiocordyceps sinensis) or Cordyceps militaris?
- Extract rather than powder: Check how many milligrams of extract each capsule contains.
- No unnecessary additives: Ideally, the ingredients list should contain only the extract and the capsule shell.
- Laboratory testing: Reputable manufacturers have their batches tested for contaminants such as heavy metals and make the results available.
How to take it and safety
Follow the recommended serving size on the package and take the capsules with plenty of liquid and a meal. If you're just starting out, begin with one capsule a day.
Check with your doctor before taking it if you use blood thinners or blood sugar-lowering medication or immunosuppressants, are scheduled for surgery, are pregnant, or are breastfeeding. Cordyceps is not intended for children. Mushroom extracts may naturally contain trace amounts of sulfites.
Vitalplant Cordyceps
Our Cordyceps capsules contain 400 mg of Cordyceps sinensis extract per capsule. The capsule contains nothing but the extract and a vegan shell made of hydroxypropyl methylcellulose. They come in amber glass bottles, with 90 capsules per bottle. Cordyceps is the only one of our medicinal mushrooms without organic certification—we don't have one for this raw material, so we don't label it as organic. It is also not included in our Organic Medicinal Mushroom Complex.
