Watercress

Watercress

Watercress is a dark-green leafy vegetable that grows as an aquatic plant in cool, fast-flowing streams. Watercress belongs to the cabbage family, also called cruciferous vegetables after the shape of their flowers. All cabbages, broccoli, radish, rocket, Brussels sprouts, and pungent crops such as mustard and horseradish are part of this family. The plants with the most beneficial effects are watercress and broccoli; these are also the most studied.

Watercress is a genuine vitamin- and mineral-bomb and ranks number one on the list of the most nutrient-dense fruits and vegetables. It contains more vitamins and minerals (vitamins A, B1, B6, C, K, E; iron, potassium, calcium, magnesium, manganese, zinc) than, for example, apples, broccoli and tomatoes.

Ancient medicinal power rediscovered

Around 1000 BC, the Greeks already praised watercress for scurvy, intestinal worms, mental weakness and despondency. In 400 BC, the physician Hippocrates built a clinic on Kos near large springs in which watercress was intensively cultivated. Over the last 20 years, the herb has been attracting more and more attention from major scientific institutes, especially for its regulating effect on detoxification.

Watercress therefore contains many nutrients. It is rich in vitamins K and A, and also provides plenty of folate, vitamin C and B6, calcium, potassium, zinc and iron. Most of its calories come from protein.

Watercress also contains:

– the carotenoids Lutein and Zeaxanthin, important antioxidants that protect the eyes.

– the phytonutrient chlorophyll, the green pigment in plant leaves that captures sunlight and converts it into energy.

– indole-3-carbinol (I3C), which is converted in the intestines into di-indolylmethane (DIM complex).

– a wealth of flavonoids, including the popular quercetin.

– the omega-3 fatty acid alpha linolenic acid

Unique components: the glucosinolates and isothiocyanates

In addition to a high content of vitamins and minerals, watercress also contains important sulphur-containing compounds: the glucosinolates. When chewed, these substances are converted (by the enzyme myrosinase and later in digestion by the gut flora) into a group of pungent compounds. These are the active protective substances known as isothiocyanates. The main glucosinolates in watercress are allyl isothiocyanate and PEITC (2-phenylethyl isothiocyanate).

Quality

The quality of watercress and the amount of pungent compounds it contains depend on many factors. Growing conditions largely determine the level of bioactive substances.

It proves very difficult to grow high-quality watercress in so-called hydroponics—an artificial, chemically fertilised environment. Watercress grows best in its natural habitat: fresh spring water from cool sources. Clean spring water supplies the necessary minerals and trace elements. Only organically grown watercress can guarantee a truly pure product.

Cressana, a watercress company in Zwalm (Belgium), has developed a unique freeze-drying process. Freeze-drying removes only water at low temperatures, so the activity of the fresh plant is preserved and the resulting watercress powder is guaranteed free of possible parasites.