Ants, meanwhile, are a bargain at just 200 RMB a kilo.

Emperor Qianlong ate black ants and was apparently the happiest emperor in the history of China. He died in 1799 at the ripe old age of 89, and claimed his good looks and youthfulness to be entirely due to his diet.

He was inspired by Li Shizhen’s “Compendium of Materia Medica,” which was then 200 years old, and still the most popular medical book in China. (It remained that way until 1959.) In it, Li wrote that black ants “enrich the qi, beautify skin, delay ageing and restore kidney energy.”

The emperor’s preferred recipe, ants fried with pine nuts, remains an all-time classic. It’s the best way to ingest the insects, and can today be found in restaurants across China. Deep fry 50g of black ants in vegetable oil until they become crisp, then do the same with 300g of pine nuts. Now toss them in a pan with 20g of vegetable oil and stir it all together. Add some salt and sugar, and dig in!

If you want to buy ants, know in advance that the bigger they are, the more expensive they’ll be. Organic, wild ants are also going to cost more than farmed ones. But the most expensive is the mountain-dwelling Wild Black Ant (300 RMB a kilo).

To catch this monster, professional hunters spread ground-up bones on plastic sheets, and sprinkle them with vinegar. After half an hour, huge ants will start to appear—the ant assassins will snatch them up and drown them in a bucket that’s half-filled with water. After a few days in the sun, they’re ready to be eaten.

Li Yanjun has farmed and sold ants for a decade, and talks like an entomologist businessman. “Ants are nutritional, medical and healthy,” he says. “They’re also one of the most valuable insects in China. The ant business has exploded in recent years. People realize that it’s a good medicine. Looks disgusting, but it tastes nice if you cook it in the right way.”

Which is, presumably, deep fried with pine nuts.

You can also soak ants in liquor, like a snake. After a week, the ant-guotou cocktail will be ready, but the longer you wait, the better. Drink 40ml a day for arthritis, or perhaps as an aphrodisiac.

A pre-bottled version of this recipe, Yilishen Tonic Wine, was a huge seller across China a few years ago. It advertised itself as a booster for men’s sex drive and fertility, with a discrete tag line of “Those who use, are those who know!” (谁用谁知道!Sheí yòng sheí zhī dào!) But the company has since disappeared.

“I didn’t see any effects,” said Mr. Yan, an older man who drank his own homemade ant cocktail. “Plus, it was disgusting.”

Granny Chen, meanwhile, eats ants for the same reason that Emperor Qianlong did: youthfulness. “Your hair will go from grey to black,” she says, citing a friend who ate ant powder for three years.

Unlike the emperor, though, Chen uses a microwave to heat her dried ants, and then blends them in a food processor. Two spoons a day, and she’s still waiting for her hair to turn black—but she has high hopes. The only problem? “It tastes horrible and smells like urine. It’s disgusting, really.”

Far more pleasant than the thought of eating ants is the thought of a deer. It’s one of the most common sights in a TCM pharmacy, and represents longevity, happiness, luck and benevolence.