Elderberry is a flowering plant that has numerous health benefits and is pretty commonly used in jams, wines, and teas. However, what you didn’t know about the elderberry plant is that its seeds and leaves are known to be poisonous and contain deadly concentrations of glycoside, a compound which produces cyanide.

If they’re not strained properly or if they’re unripe when making jam or wine, elderberries can cause nausea, induce a coma, and even cause death. Luckily, toxic substances found in elderberries can be effectively removed by cooking them. Symptoms of eating uncooked elderberries include nausea, vomiting, and diarrhea.