Ibn al-Qayyim refers to cress in his "Prophetic Medicine" and makes reference to the variety of its uses (in reference to its seeds).
Watercress is a great superfood; gram for gram it is richer in Vitamin C than oranges, and higher in iron than spinach. It's also packed with Beta-carotene, which the body converts to Vitamin A for healthy skin and eyes.
Download An Excellent 16 page PDF Report on watercress
Watercress (nasturtium officinale) belongs to the family Cruciferea, also known as the crucifers; the mustard and cabbage vegetables. It is one of the oldest known green vegetables and has a peppery flavor similar to cress and mustard. It is an aquatic plant, meaning it grows well in water, and the best watercress is grown in pure, fast-flowing, slightly alkaline water. This avoids the risk of contamination from pollution.
Watercress contains significant amounts of iron, calcium and folic acid, in addition to vitamins A and C. The deep green leaves are also fantastic sources of the phytochemicals (plant chemicals) lutein and zeaxanthin, which act as antioxidants and can mop up potentially damaging free radicals. Quercetin, a type of flavonoid and a powerful antioxidant, is also found in greater quantities in watercress than broccoli and tomatoes.
A study conducted in 2007 found that eating watercress regularly could help cut the chances of developing cancer. The work, carried out by the University of Ulster found that watercress cut DNA damage to white blood cells - considered to be an important trigger in the development of cancer.
"The results support the theory that consumption of watercress can be linked to a reduced risk of cancer via decreased damage to DNA and possible modulation of antioxidant status by increasing carotenoid concentrations."
Another study found that watercress contained a group of compounds including one called phenylethyl isothiocyanate which together could induce cell apoptosis (cell death), stopping potential carcinogens from becoming carcinogenic and stimulating cell defenses against carcinogenic assaults.
Tips on Using Watercress
- To prepare watercress, cut off the ends of the stems and rinse thoroughly.
- Watercress will stay fresh in the fridge for a few days.
- It can be eaten raw as a salad leaf or as a vegetable, to enhance the flavor of many dishes. It makes a highly nutritious soup. Check out our recipe for watercress soup. (link)
References for further reading
-  Gill C I R at al (2007) watercress supplementation in diet reduces lymphocyte DNA damage and alters blood antioxidant status in healthy adults . Am J Clin Nutr. 85 (2), 504-510.
- Rose P, Faulkner K, Williamson G, Mithen R. 7-Methylsulfinylheptyl and 8-methylsulfinyloctyl isothiocyanates from watercress are potent inducers of phase II enzymes. Carcinogenesis 2000; 21 (11): 1983-8.
- Leclercq I, Desager JP, Horsmans Y (Aug 1998). Inhibition of chlorzoxazone metabolism, a clinical probe for CYP2E1, by a single ingestion of watercress. Clin Pharmacol Ther. 64 (2): 1449.
- Kassie E F et al (2003) Effects of garden and water cress juices and their constituents, benzyl and phenethyl isothiocyanates, towards benzo(a)pyrene-induced DNA damage: a model study with the single cell gel electrophoresis/Hep G2 assay. Chem Biol Interact. 142(3), 285-96.