Watercress (Nasturtium officinale) is a nutritious aquatic herb with a range of potential health benefits, particularly for detoxification, digestive health, respiratory health, inflammation reduction, and urinary tract health. Studies have also shown that it has a significant anti-cancer benefit.
Watercress Overview
Watercress is a fast-growing, aquatic or semi-aquatic perennial plant with small, round leaves and white flowers. It belongs to the mustard family (Brassicaceae) and is known for its peppery flavor.
Habitat
Watercress is typically found growing in shallow, running water, such as streams, springs, and ditches. It is native to Europe and Asia but is now cultivated and naturalized in many parts of the world.
Primary Compounds
- Glucosinolates (including glucotropaeolin)
- Vitamins (particularly vitamin C, vitamin K, and beta-carotene)
- Minerals (such as iron, calcium, and magnesium)
- Antioxidants (including phenolic compounds)
- Essential oils
Traditional Medicinal Uses
Watercress has been used in various traditional medicine systems for its therapeutic properties. Its primary uses include:
- Detoxification: Supports liver and kidney health by aiding in detoxification processes.
- Digestive Health: Stimulates digestion and relieves digestive discomfort.
- Respiratory Health: Helps alleviate coughs, colds, and respiratory congestion.
- Anti-inflammatory: Reduces inflammation and associated symptoms.
- Diuretic: Increases urine production and supports urinary tract health.
- Antioxidant: Protects against oxidative stress and cellular damage.
Watercress in Traditional Medicine
- European Herbal Medicine: Watercress has been used in European herbal medicine for its detoxifying and digestive properties.
- Traditional Chinese Medicine (TCM): Known as "Ji Cai," watercress is used to clear heat, detoxify, and promote urination.
Watercress Health Benefits
Detoxification:
Mechanism: Glucosinolates and antioxidants in watercress support liver and kidney function, aiding in detoxification processes.
Research Evidence: While specific clinical research on watercress as a detoxifying agent is limited, its traditional use and nutritional composition support this benefit.
Digestive Health:
Mechanism: Watercress stimulates digestion and may relieve symptoms of indigestion and bloating.
Research Evidence: Anecdotal evidence and traditional use support watercress' digestive benefits.
Respiratory Health:
Mechanism: Watercress possesses expectorant properties, helping to relieve coughs and congestion.
Research Evidence: While clinical research specifically on watercress for respiratory health is limited, its traditional use supports this benefit.
Mechanism: Antioxidants and essential oils in watercress help reduce inflammation in the body.
Research Evidence: Experimental studies have demonstrated the anti-inflammatory effects of watercress extracts.
Diuretic Properties:
Mechanism: Watercress increases urine production, aiding in the elimination of toxins and supporting urinary tract health.
Research Evidence: While specific clinical research on watercress as a diuretic is limited, its traditional use and anecdotal evidence support this effect.
Anti-inflammatory and Antioxidant
Randomized controlled trials have shown watercress has anti-inflammatory and antioxidant effects after consumption.
Cancer and Watercress
Increasing evidence is finding that watercress inhibits the development of cancer in the body. As the research has matured, active anticancer compounds in watercress are getting more attention among researchers. That’s because watercress seriously helps prevent cancer.
Researchers from the University of Minnesota tested 82 smokers for what is called NNK activation. NNK is a carcinogen – long form is also known as 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone. It is a leading cause of cancer from smoking. The smokers were given either the active compound in watercress – phenethyl isothiocyanate – or a placebo for a week. Previous research has established that phenethyl isothiocyanate or PEITC is significantly anticancer.
The researchers gave the smokers special cigarettes so they could measure NNK metabolism. They found that in just one week, NNK activation was reduced by 7.7 percent. That’s not bad for chain-smokers!
The researchers concluded:
“The results of this trial, while modest in effect size, provide a basis for further investigation of PEITC as an inhibitor of lung carcinogenesis by NNK in smokers.”
The evidence has been mounting
As hinted at above, this is not the first study showing watercress’ anticancer ability.
A 2012 study from Britain’s Edinburgh Napier University found that watercress reduces DNA damage and oxidative stress – two main components of cancer development.
The researchers studied ten healthy young men (average age 23) for four months. The men were tested before and after the study, and on a daily basis, before and after exhausting aerobic exercise. During one eight-week period, the subjects took 85 grams of watercress supplements daily. They took the supplements two hours before exercise. During the other eight-week period, they worked out without the supplements.
When given the watercress supplement, the men showed a significant reduction in reactive oxygen species levels, and reduced DNA damage. Blood samples also revealed that levels of lipid peroxidation – the major cause of artery disease – were also significantly lower when taking the watercress.
Strenuous exercise typically produces DNA damage, which the body will hopefully repair. The ability of watercress to reduce DNA damage confirms earlier research showing that watercress reduces mutation and cancer growth.
The researchers commented on this aspect of the study:
“The study demonstrates that exhaustive aerobic exercise may cause DNA damage and lipid peroxidation; however, these perturbations are attenuated by either short- or long-term watercress supplementation, possibly due to the higher concentration lipid-soluble antioxidants following watercress ingestion.”
A 2014 study from China’s First Affiliated Hospital of Guiyang Medical College found that Phenethyl isothiocyanate halted the growth of leukemia cancer cells.
Another 2014 study from the University of Pittsburgh found that isothiocyanate and sulforaphane – also present in watercress as well as broccoli and other cruciferous vegetables – can halt the growth of prostate cancer.
Georgetown University researchers established in 2011 that isothiocyanate inhibited the growth of cervical cancer and breast cancer cells.
There are other anticancer agents in watercress
Cancer researchers love to focus on one special anticancer agent. They are looking for single bullets. But nature doesn’t work like that. Nature’s anticancer foods like watercress will contain other anticancer agents to fight cancer. Yes, nature fights cancer.
Besides isothiocyanate and sulphorophane, watercress contains a host of antioxidant nutrients, including xanthophyll, beta-carotene, alpha-tocopherol and gamma-tocopherol (two forms of vitamin E), each of which have been shown to slow free radical formation in the body. As other studies have shown, this in turn can reduce the rate of DNA damage and cancer formation in the body.
REFERENCES:
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Fogarty MC, Hughes CM, Burke G, Brown JC, Davison GW. Acute and chronic watercress supplementation attenuates exercise-induced peripheral mononuclear cell DNA damage and lipid peroxidation. Br J Nutr. 2012 Apr 5:1-9.
Wang X, Govind S, Sajankila SP, Mi L, Roy R, Chung FL. Phenethyl isothiocyanate sensitizes human cervical cancer cells to apoptosis induced by cisplatin. Mol Nutr Food Res. 2011 Oct;55(10):1572-81.
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Wang Y, Wei S, Wang J, Fang Q, Chai Q. Phenethyl isothiocyanate inhibits growth of human chronic myeloid leukemia K562 cells via reactive oxygen species generation and caspases. Mol Med Rep. 2014 Jul;10(1):543-9. doi:
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