Many people believe that fruit and vegetable skins contain a large amount of nutrients and therefore eat the skins of all fruits and vegetables. However, some fruit and vegetable skins can easily cause illness or poisoning when consumed, so these skins should be avoided.
Potatoes: Potato skins contain "solanine," which can cause poisoning when it accumulates to a certain level in the body. Because the poisoning it causes is chronic and its symptoms are not obvious, it is often overlooked.
Persimmons: When unripe, tannic acid is mainly found in the persimmon flesh, but after ripening, it concentrates in the skin.
After entering the human body, tannic acid reacts with proteins in food under the action of stomach acid to form a precipitate—bezoar, which can cause various diseases.
Sweet Potatoes: Sweet potato skins contain a lot of alkali, and eating too much can cause gastrointestinal discomfort. Sweet potato skins that are brown or blackish-brown are infected with "black spot disease," which can produce "ipomeamarone" and "ipomeamarol." When these enter the body, they can damage the liver and cause poisoning. In mild cases of poisoning, symptoms include nausea, vomiting, and diarrhea. In severe cases, it can lead to high fever, headache, shortness of breath, convulsions, vomiting blood, coma, and even death.
Ginkgo: The fruit skin contains toxic substances such as "ginkgolic acid," "ginkgolic acid," "ginkgolic acid," and "ginkgol." When these enter the human body, they can damage the central nervous system and cause poisoning. Additionally, the cooked ginkgo nut should not be eaten in large quantities.
Water Chestnuts: Water chestnuts often grow in paddy fields, and their skins can accumulate harmful and toxic biological waste and chemicals. Additionally, water chestnut skins also contain parasites. If you eat unwashed water chestnut skins, it can lead to disease.