The peels of fruits and vegetables are rich in nutrients and active ingredients, so it's important to eat them with the peel on for the body to fully absorb them. While this may seem like you're getting the "full nutrition" from the food, some "unwanted elements" could also be mixed in and consumed along with it.
Dishes like beef stew with potatoes and Di San Xian are classic favorites on many people's tables. Many people boil potatoes with their skins on, thinking that high heat solves all problems. This is not the case. Potatoes contain a substance called "solanine" to resist pests and diseases. The content of solanine is higher in the potato peel, and it can cause poisoning if it accumulates in the body to a certain extent. Potatoes with green skin or sprouts have an even higher solanine content, and excessive consumption can cause a series of gastrointestinal reactions such as nausea and vomiting. Therefore, potatoes must be peeled before cooking.
Sweet potatoes are nutritious, but they are alkaline foods, and eating too many can cause "heartburn." The skin of sweet potatoes contains even more alkaline, so eating them with the skin on often can cause gastrointestinal discomfort. Furthermore, sweet potato peels that are brown or have dark brown spots may be infected with "black spot disease," which can cause poisoning after consumption.
Water chestnuts are sweet, crisp, and refreshing, making them a favorite for many. However, the skin of water chestnuts may contain parasites such as liver flukes. Eating the skin of inadequately washed water chestnuts can also lead to illness.
Although ginkgo has many benefits, it is slightly toxic and should not be eaten in large quantities. The outer skin, in particular, contains toxic substances such as "ginkgolic acid," and excessive consumption can damage the central nervous system and cause poisoning. When eating them, not only should the inner skin be removed, but the cooked ginkgo nuts themselves should also be consumed in moderation.
In addition, due to the large use of chemical fertilizers today, nitrate contamination in fruits and vegetables is a serious problem. Therefore, it is recommended to peel fruits and vegetables whenever possible. This is especially true for fruits like apples, pears, and grapes, which have longer cultivation times and better taste, as their skins often contain many microorganisms, pesticides, and other residues. Therefore, there is no need to risk your health for a little extra nutrition.