The functions of water chestnuts are to clear away heat and eliminate phlegm, which is helpful for clearing the intestines and urinary tract, and is beneficial to people's dietary health. Contraindications for eating water chestnuts are those with weak spleen and stomach and those with blood stasis.

Water chestnuts have strong growth adaptability. Abroad, water chestnuts are mainly distributed wild in low-lying areas such as ponds and tidal flats in Southeast Asia, America, Europe and Oceania. Water chestnuts, which are distributed in Western countries, were introduced around the 17th century.

Cultivation has been recorded in China since the Western Han Dynasty, and there are currently more than 20 species and some variants. Except for alpine areas, it is distributed in almost all provinces and regions across the country, and its economic cultivation is mainly in the Yangtze River Basin and the areas south of it.

At present, water chestnut cultivation has formed several famous production areas, such as Guilin in Guangxi, Yuhang in Zhejiang, Gaoyou and Suzhou in Jiangsu, Fuzhou in Fujian, Xiaogan, Tuanfeng and Shayang in Hubei, Yangliu Township and Lujiang County in Anhui Xuanzhou et al.

Water chestnuts are mainly divided into wild types and cultivated types. The leaf-like stems of wild type water chestnuts are thinner, shorter, and have smaller bulbs; the cultivated type water chestnuts have thicker, taller leaf-like stems, and larger bulbs.

The plant morphology of the cultivated water chestnut varieties is very similar. The main difference is reflected in the external shape of the underground bulb. The difference is mainly reflected in the bottom of the bulb, which is divided into concave and flat umbilicus. Therefore, cultivation is also divided into Types are divided into flat-umbilical water chestnuts and concave-umbilical water chestnuts. Generally, flat-navel water chestnuts have thicker meat, more residue and higher starch content, and are more resistant to storage. Concave-navel water chestnuts have high moisture and soluble solid content, sweet taste and less residue.