Here are some examples, which can even seem frightening.

Ants

Danish restaurant Noma is run by chef René Redzepi. The name is a portmanteau of the two Danish words ‘nordisk’ (Nordic) and ‘mad’ (food). Opened in 2003, the restaurant is known for its reinvention and interpretation of the Nordic cuisine, especially for serving food with live ants. Despite its ‘strange’ menu, Noma gets about 100,000 booking enquiries a month.

One of Redzepi's signature dishes is beef tartare and ants and a 2012 pop-up restaurant in London featured live ants served with creme fraiche.

Copenhagen-based Noma, which was voted the world's best restaurant by Restaurant magazine in 2010, 2011, 2012 and 2014, closed its doors to the public after serving the final dishes in February 2017 to re-emerge in summer in new facilities, in a new location and with a new concept. In April, the entire Noma-staff moved to Mexico to open a new, temporarily, outdoor restaurant in the resort town of Tulum for seven weeks. If things proceed as planned, they will reopen as an eatery with its own vegetable farm on the edge of Copenhagen's edgy Christiania neighborhood in June.

Frog sashimi

Eating animals that are still alive is a traditional practice in many Asian food cultures. One of the most bizarre nightspots in Tokyo is the Shinjuku district; it’s home to a series of restaurants that cook up disgusting animal-based delicacies. Menu items include soft-shelled turtle, pig testicles, snake liquor and grilled salamander. However, probably the hardest dish to look at, let alone eat, is the signature dish of the Asadachi restaurant: bullfrog sashimi, which is served on ice, with a little soy sauce and a lemon slice. In 2012, a video showing a woman in Japan eating a live frog was posted on YouTube and went viral. In the video, a live frog is seen stabbed alive, stripped of its skin, and its inedible innards removed to be served as fresh sashimi on an iced platter. Though most of the frog is served dead (and raw), the meal begins by eating the frog's fresh, still-beating heart.

Japanese chef Mamie Nishide commented to Fox News this is in no way a widely-savored, traditional ethnic selection. “I just don't want you to think this is Japanese food that the Japanese enjoy. It's not. This is totally different.”

Sea urchin

Sea urchins may not look too appetizing given their spiny exteriors, but they are prized around the world for their fishy-flavored roe and flesh. Though they are often eaten raw, such as in sushi (typically called "uni"), some people prefer to eat them immediately after they are cut open. Scissors are often used to get past the protective spears. They can be eaten with a spoon, although many people prefer to lick them out with their tongues.

Yin Yang fish

Eating live fish is considered to be a delicacy in many parts of eastern Asia. In one course, diners are advised to down a shot of tiny fish, dousing them in vinegar just beforehand to make them wriggle on the way down to the stomach.

In other cases, diners sit around a bucket of live fish, picking them out by hand before dropping them into another bowl of sauce. After they have been adequately seasoned, the animals are plucked from the bowl with chopsticks and eaten alive.

Another particular food preparation method that has attracted scorn from animal rights campaigners is Yin Yang Fish - also called dead-and-alive fish. This dish consists of a deep-fried whole fish that remains alive after cooking. The fish's body is cooked while its head is wrapped in a wet cloth to keep it breathing. The fish is then covered in sauce and served live on a plate.

Oysters

These little critters spoil fast, so restaurants serve them as fresh out of the ocean as possible — and that generally means while they are still breathing when you are eating them.

Irish essayist Jonathan Swift is famous for having said, "He was a bold man that first ate an oyster." But to those of Western persuasion, oysters are the most common animal often eaten raw and alive. In fact, oysters are considered the healthiest when eaten raw on the half shell.

SafeOysters.org recommends tapping the shell lightly with your finger. "If the shell closes, the animal is alive and safe to buy. If the shell is gaping open or does not close after tapping it, the animal is dead and may harbor high numbers of bacteria which can make you ill," the site says.

Casu marzu

Casu marzu literally translating into English as "rotten/putrid cheese", is a traditional Sardinian sheep milk cheese, that contains live insect larvae (maggots). Although found in the island of Sardinia, a variety of this cheese is also found in the nearby Corsica, where it goes by the name of casgiu merzu. These larvae are deliberately introduced to the cheese, promoting an advanced level of fermentation and breaking down of the cheese's fats. The texture of the cheese becomes very soft, with some liquid (called lagrima, Sardinian for "tears") seeping out. The larvae themselves appear as translucent white worms, about 8 mm long. When disturbed, the larvae can launch themselves for distances up to 15 cm. Some people clear the larvae from the cheese before consuming while others do not. Casu marzu is considered by Sardinian aficionados to be unsafe to eat when the maggots in the cheese have died. Because of this, only cheese in which the maggots are still alive is usually eaten, although allowances are made for cheese that has been refrigerated, which can kill the maggots.

Drunken shrimp

Drunken shrimp is a popular dish in parts of China based on freshwater shrimp that are often eaten alive, but immersed in ethanol to make consumption easier. Different parts of China have different recipes for the dish. For example, the shrimp are sometimes soaked in alcohol and then cooked in boiling water rather than served live, and in other recipes cooked shrimp are marinated in alcohol after they are boiled.

Consuming uncooked freshwater shrimps may be a serious health hazard due to the risk of paragonimiasis, a food-borne parasitic infection caused by the lung fluke, most commonly Paragonimus westermani. It infects an estimated 22 million people yearly worldwide. It is particularly common in East Asia.

Octopus

Sannakji is a dish served in Korea. It is usually seasoned with sesame seeds and sesame oil. The main component of sannakji is nakji, which is a small octopus. The tentacles are usually cut from the live octopus and brought straight out to the customer, although sometimes it is served whole.

The main “appeal” of this dish is that when chewed, the tentacles are still wriggling. But because of this, the suction cups on the tentacles are still active also, and so they can become stuck in the throat of whoever’s eating it.