Cordyceps: The Fungus That Grows From a Caterpillar (And Costs More Than Gold)

High on the Tibetan Plateau, above 3,500 metres, harvesters get down on their hands and knees every spring and comb the alpine grassland for something that looks like a twig poking out of the soil. Pull gently, and what comes up is stranger than any twig: a slender, dark fruiting body attached to the mummified body of a ghost moth caterpillar, the fungus having consumed it from the inside out over the previous winter. Locally it's called yartsa gunbu — "summer grass, winter worm." To science, it's Ophiocordyceps sinensis, and it's one of the strangest and most sought-after organisms in traditional medicine.

A Fungus Worth More Than Its Weight in Gold

Wild-harvested O. sinensis isn't cheap. Prices for the highest grades have been reported as high as $30,000 a kilo (that figure moves around a lot depending on grade and season), and in parts of the Himalaya and the Tibetan Plateau, this one fungus can account for a huge share of a household's entire cash income for the year — in some counties, close to all of it. Unsurprisingly, harvesters are now reporting it's getting harder to find. Overharvesting and a warming climate are squeezing a fungus that only grows in one of the toughest environments on Earth.

Why We Don't Use the Fruiting Body

Almost no commercial Cordyceps sinensis supplement on the market, anywhere, uses the actual wild fruiting body — the caterpillar-and-all part harvesters dig up. It's simply too rare, too expensive, and increasingly, too ecologically sensitive to use at scale. What's used instead is mycelium — the fungal "root network" — grown in controlled cultivation, either on a grain substrate or in liquid culture, without a caterpillar anywhere in sight.

We think that's the right call, and not just because it's the only realistic option. Cultivated mycelium is grown without stripping a slow-growing wild population out of a fragile alpine ecosystem. It's the same fungus, the same biochemistry, produced a more sustainable way.

Orphiocordyceps sinensis

What the Tradition Actually Says

O. sinensis has a documented history in Tibetan medicine stretching back at least 500 years, and it appears in the Ben Cao Gang Mu, the great Chinese materia medica written by Li Shizhen in 1578. In Traditional Chinese Medicine it's classed mainly as a tonic for the lungs and a balancer for kidney yang — used traditionally for fatigue, wheezing, shallow breathing and low stamina. Because it's considered to nourish both yin and yang, herbalists have long reached for it in cases of general depletion and burnout, rather than for one specific complaint.

What's Actually in the Extract

The compound most associated with Cordyceps is cordycepin (3'-deoxyadenosine), a close relative of the nucleoside adenosine — and in O. sinensis specifically, it's adenosine itself that tends to predominate. Alongside these nucleosides sit polysaccharides and other bioactive compounds, some of which need hot water to draw out, others alcohol. That's why we make ours as a broad-spectrum dual extract — an alcohol extraction followed by a hot water extraction, combined into one — so you're getting more of what the fungus actually has to offer, not just the fraction that dissolves in one solvent.

Why People Take It

Traditionally and in early research, O. sinensis has been explored for support with respiratory complaints, kidney function, and general immune modulation. Cordycepin itself has attracted a fair amount of laboratory interest — including early studies looking at antiviral activity and effects on inflammation — though it's worth being clear that most of this evidence is still at the cell-study or animal-study stage rather than large human trials. We'd rather say that plainly than oversell it. Two areas come up more than any other, though, so they're worth their own space.

Energy, Stamina and Endurance

This is probably the single most common reason people reach for Cordyceps. In Traditional Chinese Medicine terms it ties back to its role as a lung and kidney tonic — the lungs said to "rule qi and the flow of air," the kidneys storing jing, the body's reserve of vitality — which is why it's traditionally used for fatigue, low stamina, and the kind of depletion that follows sustained physical or mental stress.

Modern research interest follows a similar thread, looking at plausible mechanisms rather than folklore alone: how compounds in Cordyceps support ATP production (the energy currency your cells actually run on), help with lactic acid clearance after exertion, improve oxygenation of blood and tissue, and support healthy blood flow. It's a large part of why it's become popular with people training hard or recovering from illness.

Where we want to be careful is overclaiming. Most of this evidence still sits at the traditional-use, animal-study and cell-study stage rather than large, well-controlled human trials in athletes, so we'd frame it as reasonable support rather than a guaranteed performance boost. One practical note: because of its effect on energy metabolism, it's generally better taken earlier in the day — some people find it disrupts sleep if taken in the evening.

Male Hormonal Health

O. sinensis also has a long history of traditional use for male sexual and hormonal health — low libido, erectile difficulties, and the general hormonal decline associated with andropause all appear in the traditional indications for this fungus.

There's a biological rationale behind that. A 2017 review published in the Journal of Food and Drug Analysis looked at O. sinensis mycelium, along with cordycepin and its soluble protein extracts, and found they upregulated steroidogenesis (the body's hormone-production pathway) and increased testosterone production, including in living animal models.

This is exactly why the caution below matters. Raising testosterone can be a genuine benefit if you're dealing with low libido or age-related hormonal decline — but that same mechanism is precisely why it isn't appropriate for anyone with hormone-sensitive prostate cancer or on hormone therapy. Same fungus, same mechanism, very different outcome depending on who's taking it. It's a good reminder that "natural" doesn't mean "safe for absolutely everyone."

A Few Things Worth Knowing

O. sinensis isn't neutral. Research suggests it can raise testosterone, which means it's generally not recommended if you have, or have had, hormone-sensitive (androgen-driven) prostate cancer, or you're on hormone therapy — do check with your doctor first. It's also sensible to avoid it in pregnancy, since cordycepin is an adenosine analogue and there isn't enough safety data to say otherwise. It may increase the effect of blood-thinning and blood-sugar-lowering medication, and can interact with immunosuppressants, so if you're on any regular medication, a quick conversation with your GP or pharmacist is worth having. As with most mushroom extracts, it's also sensible to stop taking it about two weeks before any planned surgery.

None of this makes it a fungus to be afraid of — it just makes it one worth taking seriously, the way you would any active botanical.

You'll find ours in the shop as the Cordyceps Broad Spectrum Dual Extract (50ml) — grown, not dug up, and made the same careful dual-extraction way as the rest of our range.

As ever — this is educational information, not medical advice. If you're pregnant, on medication, or managing a health condition, speak to a healthcare practitioner before adding any new supplement to your routine.