Why is watercress the healthiest vegetable in the world?

What is WATERCRESS? Identification name: Nasturtium officinale R. Br. Family: Brassicaceae Habitat: native to Europe, Russian Asia Medicinal parts: leaf, flower, seed Key chemical constituents: its active principles are said to be at their best when the plant is in flower. It contains mustard glycosides, mustard oil, glucosinolates, minerals, vitamins, chlorophylls, carotenoids, flavonoids, coumarins. Specifically, magnesium, manganese, iron, phosphorus, iodine, copper, calcium, nicotinamide; vitamins A, B2, B6, B9, C, K, E. Properties and uses: watercress is diuretic, depurative, balsamic, stimulating. It activates skin perspiration, it clears the airways from excess or unwanted secretions. As a salad it promotes appetite. Watercress poultices heal ringworm. Curiosity: traditionally used for scurvy and tuberculosis. Culpepper says that the leaves bruised or the juice will free the face from blotches, spots and blemishes, when applied as a lotion. Caution: watercress is generally well tolerated; but in large amounts it can cause gastric mucosal irritation, stimulate menstruation, have abortifacient effects. In some people can cause allergy with breathing problems, tightness in the throat or chest. Excessive or prolonged use of watercress may damage the kidney. Drug interactions may occur, increasing the effects of lithium, chlorzoxazone; and antagonising warfarin. Watercress, when eaten fresh, can cause pain in the bladder. It is important to wash it thoroughly to avoid distomatosis, a parasitic disease by flatworms, causing abdominal pain, nausea, jaundice, anemia, fever. Its use is contraindicated in gastroduodenal ulcers, nephritis, pregnancy, breastfeeding.

​According to the Centers for Disease Control and Prevention (CDC) the healthiest vegetable in the world for vitamin and mineral content is WATERCRESS. The comparison was made between spinach, chard, beet greens.

References The CDC Confirmed This Is The Healthiest Vegetable In The World (yahoo.com). Grieve, M. A Modern Herbal: the Medicinal, Culinary, Cosmetic and Economic Properties, Cultivation and Folk-Lore of Herbs, Grasses, Fungi, Shrubs, & Trees with All Their Modern Scientific Uses. Dover Publications,1971. Weiss, Rudolf Fritz. Weiss's Herbal Medicine. George Thieme Verlag, 2001. Campanini, Enrica. Dizionario di fitoterapia e piante medicinali. Tecniche nuove, 2012. Natural Medicines, 2019. Frattola, Ida. Piante Medicinali Italiane. Edizioni Planta Medica, 2001.