Every winter, from November to December, is the peak season for water chestnuts. With a purplish-black skin, white flesh, a sweet and juicy taste, and a crisp texture, water chestnuts can be enjoyed as both a fruit and a vegetable. Since ancient times, they have been praised as "the pear of the earth," while people in the north refer to them as "the ginseng of Jiangnan."
Water chestnuts are rich in protein and carbohydrates but are not high in calories. Traditional Chinese medicine considers water chestnuts to be a "cold" nature food. It can clear heat and purge fire, while also providing nutrients. It is very effective for reducing fever in its early stages, with about 10 being an appropriate serving size. It also has properties to cool the blood and detoxify, promote urination and bowel movements, resolve dampness and reduce phlegm, and aid digestion and relieve bloating.
Wu Jutong, a famous Qing dynasty expert on febrile diseases, created a renowned remedy for thirst caused by febrile illness that damages body fluids called "Five-Juice Drink." This drink is made by combining the juice of water chestnuts, pears, lotus root, reed rhizome, and Ophiopogon japonicus. All five juices are sweet, cold, and nourishing to the yin, making them suitable for patients at the onset of a fever or after a high fever has subsided. However, they should not be consumed during a high fever. During seasons with many respiratory infectious diseases, eating fresh water chestnuts can also help prevent and treat diseases such as cerebrospinal meningitis, measles, whooping cough, and acute pharyngitis.
Children often experience fevers in the winter, and water chestnuts are also very suitable for them. They not only help reduce fever but also promote the development of children's teeth and bones.
This is because the phosphorus content in water chestnuts is relatively high among root and tuber vegetables. It promotes human growth and development and meets the needs of physiological functions. At the same time, it can also promote the metabolism of the body's three major substances: sugar, fat, and protein, and regulate the acid-base balance. British research on water chestnuts also discovered a heat-unstable antibacterial component called "puchiin," which has a certain inhibitory effect on Staphylococcus aureus and Escherichia coli, and can also lower blood pressure. This substance also has a preventive and therapeutic effect on lung, esophageal, and breast tumors.
However, water chestnuts should not be eaten raw. Since they grow in mud, their outer skin and interior may be contaminated with numerous bacteria and parasites. They must be washed thoroughly and cooked thoroughly before consumption, and cooked water chestnuts are even sweeter.