Can Watercress Cure Cancer?

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October is Breast Cancer Awareness month, so I want to share some little-known facts about a certain superfood vegetable and its impact on breast health for cancer patients. Even though many doctors still debate the role of nutrition in health, and suggest that only conventional Western medical treatments like chemotherapy is needed, I still feel strongly that your dietary choices matter and that they may improve outcomes. I believe this is true whether or not you use chemotherapy.  Whatever stage you’re at, making changes for the better matters. Doctors may pooh-pooh this thinking, but all of us around here know that eating specific foods can (and does) have a positive impact on health outcomes.

Chemotherapy is associated with challenging side effects which may range from a full-on allergic reaction or more commonly, nausea and vomiting, weight loss, severe hair loss and profound fatigue. This may be due to the mitochondrial damage and “drug mugging” nutrient depletions.

In fact, many patients undergoing more than a few rounds of chemo may face more more daunting complications such as plummeting white blood cells (WBC), leaving them wide open to life-threatening infections. There are dozens of potential complications such as kidney or heart failure, bladder issues and bone marrow suppression Research clearly shows that a large number of people give up and fail to adhere to these conventional medical treatments, often due to the side effects. Many stop altogether or they begin to integrate various holistic remedies and dietary changes.  One dietary rockstar they may wish to integrate into their diets is watercress.

Watercress belongs to the cruciferous vegetable family, as do broccoli and cauliflower, but it’s not as popular in the US as those. It is green and has beautiful leaves, and it’s found in the produce section.  (Don’t confuse watercress with water chestnuts, which are delicious white aquatic vegetables commonly found in Asian cuisines.)

Watercress is a leafy vegetable, rich in natural folate and other B vitamins. I decided to give it some attention today because it contains powerful tumor-fighting compounds. Plus, we already know from empirical evidence that 30 to 40 percent of all cancers somehow benefit or respond from proper nutrition.

Starve the cancer cells
Researchers have investigated how watercress can be beneficial in breast and other cancers. In a study published in the British Journal of Nutrition, a group of breast cancer survivors went through a phase of fasting prior to consuming a serving of watercress about the size of a cereal bowl (approximately 80 grams of watercress).  Blood samples were then taken from the women at intervals over the next 24 hours.

Their blood evaluations found rather significant levels of a plant phytochemical compound called phenylethyl isothiocyanate, or PEITC for short.  We know that PEITC starves cancer cells.

This PEITC (prevalent in watercress) inhibits a protein called HIF (Hypoxia Inducible Factor) which is responsible for signaling normal tissue around the tumor to send oxygen and nutrients TO tumor cells. HIF doesn’t play nice, it makes your own cells boost cancer growth.  Watercress gives us PEITC, which blocks HIF and that’s good for the breasts and the prostate!  And actually, all reproductive organs in both men and women (testicles, uterus, ovaries, etc).

Am I saying watercress cures cancer?
Of course not, but eating certain foods like watercress can’t hurt, it can only help you, and more than anything, it puts you in a proactive position.  Let’s face it, hearing the word “cancer” is heart-stopping. Having something you can do that is so simple is empowering.  There is much more you can do too, but this article’s focus is about watercress, so let me share more with you.

The researchers in the study actually validated the effects of the watercress compound PEITC (they weren’t guessing!) They physically measured blood levels of that HIF in their bloodstream and saw it declining progressively after eating watercress.  That is just so amazing!

Another study back in 2004 took a different look at how PEITC impacts the speed at which cancer cells grow (termed “proliferation”) and tumorigenesis (the formation of tumors). The scientists were able to confirm that watercress inhibits cancer cell growth and not only that it makes cancer cells commit suicide, a process called apoptosis.  You want apoptosis to happen.  It means the party’s over for the cancer cells!

You know how some people gossip and spread negativity? Cancer cells do the same exact thing, they have enzymes for the sole purpose of spreading their dangerous cells.

TPA and MMP9 need to be controlled
It’s the presence of some enzymes in cancer cells like one called 12-O-tetradecanoylphorbol-13-acetate (TPA) and Matrix Metalloproteinase-9 (MMP9) that speed up the invasion of otherwise healthy cells around. So TPA and MMP9 spread the cancer, making it more lethal. Controlling those biomarkers is important.

Researchers studied how well broccoli and watercress (extracts) could suppress these two enzymes in breast cancer cells.  Scientists employed a process called, Zymographic Analysis, to see if the extracts of watercress and broccoli could inhibit the effect of these enzymes (TPA and MMP9).  Guess what?  Of course the veggies helped, and in a dose-dependent manner, meaning the higher the concentration of the veggie extracts, the more suppression of TPA and MMP9.

The blocking effects of the watercress (and broccoli) was due to two special sulfur-based compounds that naturally occur in the veggies.

Don’t host cancer again – do something while you’re healthy
I think it’s a good idea to eat watercress and I have a couple delicious recipes for you at the end of this article.  Including veggies in your diet several times a week is a good way to reduce your risk for cancer, and this is particularly important if you have a history of cancer. Even if you’re thriving right now, your body STILL needs nourishment in order to prevent you from being a host again.

Researchers at the University of Ulster in beautiful Northern Ireland published some of the most convincing and comprehensive work ever done to tease out the effects of watercress.  They published very positive results, after looking at a few important markers of cancer.

In the study, which was published in the American Journal of Clinical Nutrition, 60 participants (both male and female) ate three ounces of raw watercress every day, in addition to their normal, typical diet.  This went on for 8 weeks.  Half of the participants were smokers.

Doctors measured a lot of things:
1. DNA damage to the lymphocytes
2. Lutein (plasma)
3. Retinol (a type of vitamin A)
4. Alpha-tocopherol (a part of vitamin E)
5. Beta carotene (a vitamin A precursor)

The study found an overall reduction by 17% in basal DNA damage.  Protecting DNA is huge in reducing risk of aberrant cancer cells. The levels of antioxidants such as lutein, vitamin E and A all increased significantly. The lutein in particular spiked with levels showing a 100% increase!  Beta-carotene levels improved by 33%. Interestingly, smokers stand to benefit a lot because the DNA-protective effects of watercress appeared to be even more significant for smokers vs. non-smokers.

What does all this mean?
It’s pretty simple.  Adding watercress to your diet goes a long way in protecting your cells, DNA and reproductive tissue.  I’m not a spokesperson for watercress, I swear, I just see it as an easy, tasty way to amp up your recipes with cancer-fighting foods.

Cooked vs. Raw
You can chop them up like I do into my green salads.  I also have a delicious vegan watercress soup (see below) that I’ve made for Sam for the past 10 years! It’s the first thing I make for us when fall arrives. Eat ‘em up, the more the merrier, but it’s better if you take the time to saute, cook or steam them… otherwise eating them raw too frequently will impart the goitrogenic effects of the raw crucifers and will crash your thyroid.

Watercress is a goitrogen and I’ve talked about limiting goitrogenic foods because they can suppress iodine. You can read more about this if you read my article, The Case Against Kale.   If you suppress iodine too much, then you can’t produce adequate amounts of thyroid hormone.  So knowing that watercress is a goitrogen, it begs the question, should this be cooked, or eaten raw in order to get the most benefit?

I would say, it’s totally okay to eat watercress raw, I do it myself, but I control the portion.  I also have healthy thyroid function. I put about half a cup into my salad (washed/cut) or maybe a cup into a smoothie once a week.  I am not putting the whole head of watercress into anything, though, unless it’s cooked!  With my Watercress Soup, it’s actually cooked a little bit.  Now, what does the cancer research say?  They say it’s better to eat the watercress raw, because cooking will deactivate the the cancer-fighting enzymes called isothiocyanates.

So if you are confused, don’t be.  What I’m saying is to go ahead and eat BOTH raw and cooked forms of watercress, you’ll get the best of both worlds.  Eating both raw and cooked will still provide a lot of nourishment for your cells, especially B vitamins and antioxidants… and it will still offer all those cancer-fighting compounds. And it won’t crash your thyroid either because you’re not eating it raw in large amounts. But of course, this is just my humble opinion and what I do in my own home. You can do what you like with my blessings.

Watercress Soup
2 teaspoons flaxseed or olive oil
2 large turnips, peeled and chopped
1 large zucchini, peeled and sliced
1 leek (white and green parts), well washed
1 small onion, chopped
2 – 3 garlic cloves, chopped
4 cups water (or homemade vegetable broth)
1 bunch (or bag) watercress
1/2 bunch parsley, washed
Sea salt

In a medium saucepan, warm the flaxseed oil over medium heat. Add the turnips, zucchini, leek, onion, and garlic. Cook, stirring, until they soften slightly. Add the water or broth and simmer for 15 minutes.
Stir in the watercress and parsley, and remove from the heat. Uncover and let cool for about 10 minutes. The watercress and parsley will wilt, but will still retain their powerful enzymes. Pour everything into a Vitamix and blend on high for 1 or 2 minutes. Add more water if you prefer a thinner soup. Season to taste with more sea salt. Serve hot with crusty bread and butter.

Autumn Watercress Salad
1/8 cup flax seed oil
1/8 cup olive oil
1/8 cup red wine vinegar
1 tablespoon maple syrup
1 teaspoon Dijon mustard
1 tablespoon fresh parsley, chopped
1 tablespoon fresh chives, chopped

1 head green leaf lettuce, washed & torn into pieces
1 bag fresh watercress, washed and chopped
1/2 pound fresh beets, roasted until tender, peeled and sliced into rounds
8 ounces fresh burrata cheese
3 ounces mild bleu cheese, crumbled
1/2 cup walnuts, toasted

Make dressing: shake all dressing ingredients in a Mason jar with a tight-fitting lid.  Taste and add salt and pepper as needed.  Store in refrigerator until ready to use, then shake again vigorously before pouring over salad.
Make salad: set beet rounds on a chopping board, then top with a little burrata.  Place greens in a salad bowl, then arrange beets attractively over the greens.  Sprinkle bleu cheese and walnuts over top of salad, then dress lightly.  Serve with remaining dressing on the side.


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