Watercress

Watercress (Nasturtium officinale) is a perennial, water-loving plant from the family of the crucifers (Brassicaceae). It prefers to grow in clear, flowing waters and is widespread in Europe, Asia, and North America. Since antiquity, Watercress has been valued both as a food and as a medicinal plant.

What benefits does Watercress provide?

Watercress is held in particularly high regard in traditional medicine due to its valuable constituents and health-promoting properties. Studies have also examined the properties of the plant and partially confirm the health-promoting effects. As always, however, the studies should be viewed critically, as not all results are readily transferable to the general population.

  • Rich in vitamins and minerals: Watercress contains high amounts of vitamin C, A, K, and B vitamins as well as iron, calcium, and iodine, which makes it a nutrient-rich food. (1)
  • Antioxidant effect: The glucosinolates and flavonoids it contains act as strong antioxidants that can protect cells from oxidative stress and damage caused by free radicals. (1,2,3,4,5)
  • Support for the immune system: Due to its high micronutrient content, Watercress contributes in several ways to the maintenance of normal health.
  • Detoxifying effect: Watercress is traditionally used to support liver and kidney function and to promote detoxification. (1,3,6,7)
  • Respiratory conditions: In naturopathy, it is used to relieve coughs, bronchitis, and other respiratory conditions.
  • Antibacterial effect: Studies have shown that Watercress has an antibacterial effect (2)
  • Anti-inflammatory effect: According to studies, Watercress can help alleviate inflammation (2,4)
  • Estrogen-inhibiting effect: Scientists have found that Watercress possesses estrogen-inhibiting effects that could potentially be of significance in cancer therapy and hormone regulation (1,2,4).

How does Watercress work?

The health-promoting effects of Watercress can be attributed to its bioactive constituents; here is a selection of important active compounds, although Watercress contains significantly more bioactive components than just these three:

  • Glucosinolates: These sulfur compounds are converted in the body into isothiocyanates, which can produce various effects (1,2,8).
  • Vitamin C: Promotes immune defense, supports collagen formation, and acts as a strong antioxidant (9).
  • Flavonoids: Plant compounds with antioxidant, anti-inflammatory, and vascular-protective properties (5,10,11).

Side effects and risks

Although Watercress has numerous positive properties, precautions should also be observed:

  • Stomach irritation: When consumed in excess, Watercress can cause stomach complaints or irritation of the mucous membranes.
  • Pregnancy and breastfeeding: During pregnancy and breastfeeding, consumption in large amounts should be avoided, as the effects have not been sufficiently studied.
  • Interactions: People taking blood-thinning medications should be cautious, as the high vitamin K content could influence their effect.

Conclusion

Watercress is a nutrient-rich plant with diverse health benefits; among other things, studies have identified antioxidant, anti-inflammatory, and detoxifying properties from which one could benefit. Despite its positive effects, it should be consumed in moderation to avoid side effects, and more studies are needed before definitive statements can be made about the plant's effects.

Sources:

  1. Panahi Kokhdan, E., Khodabandehloo, H., Ghahremani, H., & Doustimotlagh, A. H. (2021). A Narrative Review on Therapeutic Potentials of Watercress in Human Disorders. Evidence-based complementary and alternative medicine : eCAM, 2021, 5516450. https://doi.org/10.1155/2021/5516450
  2. Klimek-Szczykutowicz M., Szopa A., Ekiert H. Chemical composition, traditional and professional use in medicine, application in environmental protection, position in food and cosmetics industries, and biotechnological studies of Nasturtium officinale (watercress) - a review. Fitoterapia. 2018;129:283–292. doi: 10.1016/j.fitote.2018.05.031.
  3. Sakil M., Polash M., Afrin S., Hossain M. Evaluation of morphological traits, phytochemical compositions and antioxidant properties of watercress leaves. Progressive Agriculture. 2019;30:10–16. doi: 10.3329/pa.v30i0.41552.
  4. Shahani S., Behzadfar F., Jahani D., Ghasemi M., Shaki F. Antioxidant and anti-inflammatory effects of Nasturtium officinale involved in attenuation of gentamicin-induced nephrotoxicity. Toxicology Mechanisms and Methods. 2017;27(2):107–114. doi: 10.1080/15376516.2016.1258748.
  5. Gill C. I., Haldar S., Boyd L. A., et al. Watercress supplementation in diet reduces lymphocyte DNA damage and alters blood antioxidant status in healthy adults. The American Journal of Clinical Nutrition. 2007;85(2):504–510. doi: 10.1093/ajcn/85.2.504.
  6. Sadeghi H., Azarmehr N., Razmkhah F., et al. The hydroalcoholic extract of watercress attenuates protein oxidation, oxidative stress, and liver damage after bile duct ligation in rats. Journal of Cellular Biochemistry. 2019;120 doi: 10.1002/jcb.28749.
  7. Karami M., Mostafazadeh M., Sadegh H., et al. Nephroprotective effect of nasturtium officinale (watercress) ethanol extract and vitamin E on vancomycin-induced nephrotoxicity in Ra. Jundishapur Journal of Natural Pharmaceutical Products. 2017;13 doi: 10.5812/jjnpp.67178.
  8. Syamsianah A., Anggraini H. Control of Lipid Profile on Diabetes Mellitus Animal Models with Watercress and Black Rice Bran. Semarang, Indonesia: Prosiding seminar nasional & internasional; 2016.
  9. Office of Dietary Supplements. (n.d.). Vitamin C - Health professional fact sheet. U.S. National Institutes of Health. Retrieved February 13, 2025, from https://ods.od.nih.gov/factsheets/VitaminC-HealthProfessional/
  10. Izzi V, Masuelli L, Tresoldi I, Sacchetti P, Modesti A, Galvano F, et al. The effects of dietary flavonoids on the regulation of redox inflammatory networks. Front Biosci. 2012;17:2396–2418. doi: 10.2741/4061.
  11. Kay CD, Hooper L, Kroon PA, Rimm EB, Cassidy A. Relative impact of flavonoid composition, dose and structure on vascular function: A systematic review of randomised controlled trials of flavonoid-rich food products. Mol Nutr Food Res. 2012;56:1605–1616. doi: 10.1002/mnfr.201200363.