True to its name, củ năn (water chestnut) grows in water. A water chestnut is nearly 70 percent water, 19 percent starch, 2.25 percent protein, 0.19 percent fat, and 1.58 percent essential minerals.

In Oriental medicine, water chestnuts are used to cool the body, clear sputum, and treat fever, dehydration, sore throat, coughs, bronchitis and red eyes. They are diuretics and relieve urinary tract infection, according to doctors Hoang Khanh Toan and Nguyen Duc Quang. Dr. Toan adds that water chestnuts can stop the bleeding associated with hemorrhoids or severe dysentery.

Here are some simple water-chestnut remedies, the first five from Dr. Toan:

Recipe 1:

Wash and peel half a kilogram of water chestnuts, chop them roughly, juice them in a blender. Filter the juice through a seive or clean cloth into a glass. Then crush 250g rock sugar and mix it with the juice. This concoction cools the body, reduces excess sputum, and eases sore throat, bronchitis or tonsillitis.

Recipe 2:

For this you need 500g water chestnuts and 500g honey. Wash and peel the chestnuts, chop them into small pieces, juice them in a blender, and filter the juice through a clean cloth into a glass. Stir in the honey and drink this to cool the body, clear up sputum, and fortify the upper respiratory tract to keep it free of infection.

Recipe 3:

Take 200g water chestnuts, 200g lotus rootstock, 200g pear and 15ml honey. Begin by washing and peeling the chestnuts, lotus rootstock and pear. Chop everything into small pieces, juice together in a blender, filter the juice through a clean cloth into a glass, and stir in honey to taste. This drink cools the body, eases coughing, and prevents urinary tract infection, bronchitis, sore throat, hemorrhoids and water loss from fever.

Recipe 4:

Take 200g water chestnuts, 80g rock sugar, 350g sugarcane, and 200g carrots. Wash and peel the chestnuts, soak in salt water for 10 minutes, and rinse again. Peel and slice the sugarcane into medium pieces, soak in salt water for 10 minutes, and rinse again. The carrots should be washed, peeled and chopped into small pieces too. Place the lot with rock sugar in a pot, cover with water, cook for 30 minutes, then let stand until the liquid cools down. This beverage cools the body and gets rid of excess mucus. It’s also good for treating urinary tract infection, sore throat, retention of urine, chronic nephritis, and high blood pressure.

Recipe 5:

Take 100g water chestnuts, 100g fresh lemons and one liter of boiled water. Wash and peel the chestnuts, and slice them thinly. Wash and peel the lemons, and cut them into two. Simmer the chestnuts and lemons, with one liter of water for 15 minutes. This drink cools the body, treats upper respiratory tract infection and lowers blood pressure.

Dr. Quang suggests two remedies using water chestnuts:

Recipe 1:

Mix a half glass of water-chestnut juice and a half glass of light white alcohol. This drink is used to help treat bloody stools. Contact your doctor immediately if blood persists.

Recipe 2:

Wash, peel and chop 120g of water chestnuts, juice them in a blender, pour the juice into a glass and refrigerate. The cool juice is good for a swollen or otherwise sore throat.

A word of warning: water chestnuts are unsuitable for people with indigestion, watery defecation, cold limbs, or stomach pain from eating fresh and cold cooking.