Some everyday foods can turn dangerous if they’re not processed, prepared, or cooked properly. Cassava contains compounds (linamarin, lotaustralin) that can release cyanide unless the roots are peeled, soaked, and thoroughly cooked.  Starfruit contains neurotoxins that can be especially harmful to people with kidney disease. Cherry pits, bitter almonds, and apple seeds carry cyanogenic compounds that convert to cyanide in digestion.

Other risks come from foods that produce or contain poisons under certain conditions. Green potatoes (and their sprouts or skin) can accumulate solanine—a glycoalkaloid toxin that causes nausea, vomiting, and neurological symptoms. Raw cashews and mango skin can harbor urushiol, the same irritant in poison ivy, which may trigger allergic reactions. The Japanese pufferfish (fugu) is famously notorious: it contains tetrodotoxin, which can be fatal if the fish isn’t expertly prepared to remove its poisonous parts.

Other “hidden dangers” include nutmeg (in large doses it may induce hallucinations, seizures, or other toxic effects), wild mushrooms (such as the death cap, which carry potent toxins), and plant parts like raw kidney beans, elderberry seeds/skins, or rhubarb leaves. When consumed improperly or raw, these may trigger severe illness or even death.

Understanding which foods carry hidden risks—and how to safely process, cook, or avoid them—can be critical. What seems like an innocuous ingredient may, under the wrong handling, become lethal. If you like, I can also prepare a guideline or infographic for safe preparation of some of these high‑risk foods.