Truffles have been prized for centuries in European cuisine for their unique taste and smell. But what exactly are they? They're the fruiting bodies of fungi that are hidden underground in the roots of oak and hazelnut trees. Recently, a group of Italian researchers found that black truffles, possibly the second most commercially desired truffle (after the Italian white truffle), contain a molecule that acts similar to the active chemical in marijuana, causing a euphoric high after it's eaten.

Mauro Maccarrone of the Campus Bio-Medico University in Rome and colleagues published their findings in 2012. They wrote that the highly prized black truffles were found to produce anandamide, a compound that triggers the release of mood-enhancing chemicals in the human brain through a similar biological mechanism as tetrahydrocannabinol (THC), the chemical responsible for the same effects in marijuana.

Often called the bliss molecule, anandamide can have a positive effect on mood, appetite, pain and memory. Anandamide was named after the Sanskit word "ananda" which means "joy", "delight" or "bliss". The molecule was first isolated in 1992 by Israeli chemist Raphael Mechoulam, who had been researching the effects of marijuana on humans since the 1960s. He was the one who identified THC as the active ingredient in marijuana back in 1964.

Maccarrone and his team found that anandamide was present in the fungi, but the receptors needed to trigger the effects of it were absent, suggesting to the scientists that the truffles don't make this chemical for themselves, but for the animals that hunt the truffle. Why would the truffles want animals to dig them up and eat them? Because truffles reproduce when their spores are spread through the feces of the animals that eat them.

A heart-shaped black truffle

Cross-section of a heart-shaped black truffle. (Photo: AleksandarMilutinovic/Shutterstock)

Truffles are considered wild, meaning they are not grown in greenhouses or farms; they are difficult to cultivate through human means — hence their allure and value.

So how do you go about finding them? With the help of specially trained truffle-detection animals.

For centuries, pigs were used for their natural truffle-detection abilities. More recently, dogs have been used in truffle hunting since they are easier to manage and train. Regardless of the animal used, their behavior upon finding and eating the truffle is "frantic," because of the anandamide, say the reseachers. They can't get enough and are looking for more — hence the reproduction of the truffle is ensured.

Anandamide has also been found in chocolate (which costs just a smidge less than a truffle) and has even been found in the blood of runners after a particularly invigorating workout, and might very well be responsible for that "runners high" that so many running enthusiasts experience. The downside to anandamide? Unlike THC, it breaks down quickly in the body and doesn't give the same lasting high. 

Black truffles can go for up to $1,200 per pound, so if you're looking for a less expensive alternative to marijuana, it may not be your answer. But if you find yourself eating a truffle in a posh Italian restaurant and thoroughly enjoying the experience — well, now you know why.

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