Watercress is a vegetable in the Brassicaceae family. It has a peppery taste and is related to broccoli, cauliflower, and rocket.
Watercress consumption has been associated with various anti-cancer effects.
Watercress consumption can also stimulate anti-oxidant enzymes, which is thought to reduce DNA damage. Watercress is also a good source of lutein.
Watercress and other members of the Brassicaceae family contain compounds called isothiocyanates. Isothiocyanates include sulforaphane, diindolylmethane and phenethyl isothiocyanates (PEITC). Compared to other Brassicaceae plants, watercress contains more PEITC. These compounds help the body protect against a variety of compounds, including carcinogens.
There is minimal human evidence to support these claims, but two human studies have found a degree of reduced DNA damage in otherwise healthy people after they added watercress to their diet.