杏吧原创

I went hunting for a zombie fungus worth more than its weight in gold

The fungus yartsa gunbu, which grows by turning caterpillars into zombies, is prized in traditional medicine, but its harvest is having an increased ecological impact on its native Himalayan home
Harvesting yartsa gunbu provides an income for many people in Nepal
Jitendra Raj Bajracharya/ICIMOD

The hunt for a fungus that is worth more than its weight in gold as a traditional medicine is transforming the Himalayan landscape on which it grows. To learn more, I have come to the in Kathmandu, Nepal, where I am watching the preparation of a tea made from yartsa gunbu, a 鈥渃ure-all鈥 fungus that may be the world鈥檚 most expensive natural resource.

Tsultrim Rabsel grinds and mixes the fungus with 16 rare herbs and medicinal plants. He hands a tea sachet to Tashi Tsering, who carefully places the grinds within. 鈥淢edicine鈥檚 ready,鈥 he says.

These men are amchis, a Tibetan term that loosely translates to聽doctor. They specialise in聽traditional Tibetan medicine, a聽field that mixes science and belief and uses rare ingredients for聽spiritual and health tonics.

While its price and scarcity means yartsa, or Cordyceps sinensis, hasn鈥檛 been studied much in the West, researchers in China, Nepal and India have found potential for and for , and , as well as possible antioxidant, anti-inflammatory and antiviral effects. It has also been hailed as an aphrodisiac 鈥 sometimes dubbed Himalayan Viagra 鈥 and there are real links to (although other claims, like it , are ).

A close-up view of yartsa gunbu
Adam Popescu

To many who take yartsa, this mix of is what makes it worth more than its weight in gold, selling for around $150,000 a kilogram in China. Globally, the market is .

鈥淲hy is it attractive? Because of聽the idea that it鈥檚 wild and pure,鈥澛爏ays , a specialist in Himalayan economies at the International Centre for Integrated Mountain Development. 鈥淭here is聽truth to the science, not all, but聽enough to make people believe. Belief is key.鈥

That belief is aided by yartsa鈥檚 unusual origins. It is produced when larvae of ground-dwelling ghost moths are聽infected with the parasitic Cordyceps fungus, which encases the caterpillars with its root-like mycelium, hence another of its names: caterpillar fungus. When the caterpillar surfaces to die, the fungus blooms with a needle-like stalk. The life cycle of the Cordyceps genus inspired the zombie-like humans in the video game and TV show The Last of Us.

The high price of yartsa 鈥 which only grows in high pastures in India, Nepal, Bhutan and China 鈥 makes harvesting it the main income for many impoverished communities here. Booming demand has improved living standards, but it is also having a聽.

Yartsa takes years to grow and is聽being harvested unsustainably. Using a pickaxe to remove the mycelium strips away the soil that the聽moths need from the hillside, speeding up erosion caused by climate change. Research also shows that yartsa harvests pollute rivers and result in deforestation.

Warming also has a direct impact, as less snow means less yartsa, since it needs moisture to grow. . (In Bhutan, mean winter temperatures have increased by 3.5掳C to 4掳C across most of yartsa鈥檚 habitat.)

Tashi Tsering at the Sowa Rigpa Institute of Traditional Medicine
Adam Popescu

Demand, habitat deterioration and climate change all contributed to the International Union for Conservation of Nature , stating the fungus had declined by at least 30 per cent over the past 15聽years due to overharvesting.

鈥淚t鈥檚 too important to local economies to stop,鈥 says Dorji. Even and can鈥檛 stop the trend. 鈥淚t鈥檚 a聽luxury item,鈥 he says.

At the institute, the amchis show me pieces of yartsa that go聽for $10 each. Tsering offers me聽a聽steaming cup containing a mud-brown mixture that smells slightly putrid, a yartsa infusion called a . 鈥淵ou can take it, it聽will affect your body,鈥 he says, before I ask how. 鈥淟onger sex. More energy.鈥

I down the drink, which tastes like cinnamon and nutmeg. But I don鈥檛 feel an energy boost or a libido surge. Not long after, I am asleep in my hotel room. But is that because this 鈥渃ure-all鈥 isn鈥檛 all it is cracked up to be or because I was so exhausted from running around Kathmandu looking for it? Maybe it is a touch of both.

Topics: Medicine