Ackee Fruit

This is a fruit rich in vitamin A and protein, highly favored by Jamaicans. However, caution is needed when consuming ackee: it must be eaten before it becomes fully ripe, and you must not eat the seeds or let the skin come into contact with the seeds. The seeds contain a toxin that inhibits glucose production, leading to dangerously low blood sugar levels and potentially death.

Cassava

In some cuisines, this root is processed into mashed dishes or cakes, but only after being thoroughly cooked. When chewed raw, cassava releases the enzyme linamarase, which converts a compound in the root into cyanide—a deadly poison.

Japanese Pufferfish (Fugu)

Fugu is banned in the U.S. because it is among the most poisonous foods in the world. If improperly prepared, it can be up to 1,200 times more toxic than cyanide. Its liver and internal organs contain tetrodotoxin, a poison for which there is no known antidote. For the Japanese, especially in Shimonoseki, pufferfish is a delicacy, enjoyed in various dishes such as sashimi, fried, boiled, or cooked with miso.

Live Octopus

Octopuses are among the most intelligent creatures on Earth, with a unique nervous system. Their tentacles remain active even after being severed. In South Korea, people traditionally eat live octopus. It is chopped into pieces and dipped in soy sauce or sesame oil before being eaten. As the tentacles are still moving, they can cling to the throat and cause choking.

On average, there are six deaths per year in South Korea due to suffocation from eating live octopus. In some cases, the tentacles have even crawled from the mouth into the nasal cavity.

Casu Marzu (Rotten Cheese)

This cheese is fermented using live maggots and is not for the faint-hearted or those with stomach problems. It is made from sheep’s milk, and during fermentation, fly larvae are intentionally introduced. The maggots accelerate fermentation, and the cheese is eaten when it becomes almost liquid. At this point, thousands of live maggots are still present. While eating, maggots can leap from the plate into the eater’s face, so diners often wear protective eyewear.

Unpasteurized Cheese

Cheese made from raw (unpasteurized) milk can harbor all kinds of pathogens and harmful bacteria, posing serious health risks. Such cheeses are banned in the U.S.

Raw Cashew Nuts

Raw cashews contain urushiol, a toxic substance that can be fatal if consumed in large amounts.

Hákarl (Fermented Shark)

Greenland sharks have high levels of urea and trimethylamine oxide in their flesh. To make them edible, the meat is either hung to dry or buried underground for 3 to 5 months. According to the Canadian Food Safety Institute, consuming too much of it can cause gastrointestinal issues, nerve damage, seizures, or even death.

Rhubarb

This bright pink stalk is found in pies and jams, but its leaves should never be cooked or eaten, as they contain oxalic acid. In large quantities, this acid can be lethal.

Elderberries

Native to Canada, elderberries are delicious and safe when properly cooked. They are often used in supplements, wine, tea, jam, and pastries.
However, the leaves, branches, and seeds contain cyanogenic glycosides, which can be fatal. Eating unripe or improperly processed elderberries may cause gastrointestinal symptoms like vomiting, severe diarrhea, and nausea. In large quantities, they can cause serious illness or seizures.