Watercress plant and vegetable medical use by Ray Sahelian, M.D.
March 20 2016

Watercress is a leaf vegetable. Watercress is a member of the cabbage family, botanically related to garden cress and mustard. Watercress is a healthy addition to one's diet.

Antioxidant
Springerplus. 2015. Phenolic profile and antioxidant potential of wild watercress (Nasturtium officinale L.). Phenolic profile, antioxidant potential and pigment contents of wild watercress (Nasturtium officinale L.) were studied to assess the potential for future studies and its applications in neutraceuticals and bioactive functional ingredients. Different extracts of watercress (roots, stem and leaves) were analysed for pigment composition, total phenolic contents, and radical scavenging activity. Fourteen phenolic compounds were identified in the leaves, where coumaric acid and its derivatives, caftaric acid and quercetin derivatives were present in higher amounts. In roots, a total of 20 compounds was tentatively identified, with coumaric acid and its derivatives, sinapic acid, caftaric acid and quercetin derivatives were the major phenolic compounds. In conclusion, watercress has significant antioxidant activity and contains important phenolic compounds, which could be of potential biological interest.

Inflammation protection
Pharm Biol. Feb 2014. In vivo anti-inflammatory properties of aerial parts of Nasturtium officinale. Nasturtium officinale R. Br. (watercress) has long been used in Iranian folk medicine to treat hypertension, hyperglycemia, and renal colic. Moreover, anticancer, antioxidant, and hepatoprotective properties of N. officinale have been reported. Objective: In this study, anti-inflammatory activity of the hydro-alcoholic extract from aerial parts of N. officinale was investigated. Materials and methods: Oral administration of the hydro-alcoholic extract of N. officinale (250, 500 and 750 mg kg(-1)) was investigated on two well-characterized animal models of inflammation, including carrageenan- or formalin-induced paw edema in rats. Then, the topical anti-inflammatory effect of N. officinale (2 and 5 mg/ear) was studied on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced mouse ear edema. Finally, biopsy of the paw or ear was performed for pathological evaluation. Results: Acute toxicity tests of N. officinale in rats established an oral LD50 of >5 g kg(-1). The extract of watercress (250, 500 and 750 mg kg(-1)) significantly inhibited carrageenan-induced paw edema 1, 2, 3 and 4 h after carrageenan challenge. The extract (500 mg kg(-1)) also showed considerable activity against formalin-evoked paw edema over a period of 24 h (p < 0.001). Furthermore, topical application of N. officinale (5 mg/ear) reduced TPA-induced ear edema (p < 0.05). Histopathologically, the extract decreased swelling and the tissue damage induced by carrageenan or TPA. Discussion and conclusion: Our findings indicate potent anti-inflammatory activity of N. officinale in systemic and topical application and propose its potential as an anti-inflammatory agent for treatment of inflammatory conditions.

Watercress protects DNA, study
Watercress supplementation in diet reduces lymphocyte DNA damage and alters blood antioxidant status in healthy adults.
American Journal of Clinical Nutrition, 2007. Chris IR Gill, Sumanto Haldar, Lindsay A Boyd, Richard Bennett, Joy Whiteford, Michelle Butler, Jenny R Pearson, Ian Bradbury and Ian R Rowland. 1 From the Northern Ireland Centre for Food and Health, Centre for Molecular Biosciences, University of Ulster, Coleraine, N Ireland, United Kingdom (CIRG, SH, LAB, JW, MB, JRP, IB, and IRR), and the Institute of Food Research, Norwich Research Park, Colney, Norwich, United Kingdom (RB)
The aim of this study was to determine the effects of watercress supplementation on biomarkers related to cancer risk in healthy adults. A single-blind, randomized, crossover study was conducted in 30 men and 30 women (30 smokers and 30 nonsmokers). The subjects were fed 85 g raw watercress daily for 8 wk in addition to their habitual diet. The effect of supplementation was measured on a range of endpoints, including DNA damage in lymphocytes (with the comet assay), activity of detoxifying enzymes (glutathione peroxidase and superoxide dismutase) in erythrocytes, plasma antioxidants (retinol, ascorbic acid, {alpha}-tocopherol, Lutein, and beta-carotene), plasma total antioxidant status with the use of the ferric reducing ability of plasma assay, and plasma lipid profile. Results: Watercress supplementation (active compared with control phase) was associated with reductions in basal DNA damage, in basal plus oxidative purine DNA damage, and in basal DNA damage in response to ex vivo hydrogen peroxide challenge. Beneficial changes seen after watercress intervention were greater and more significant in smokers than in nonsmokers. Plasma lutein and beta-carotene increased significantly by 100% and 33%, respectively, after watercress supplementation. 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.