The internet loves “best of” lists. But while many of these lists involve movies, electronics, or how well someone dressed at the Oscars, until recently, I wasn’t aware there was a “best of” award for the world’s healthiest vegetable.
The competition was fierce. Kale and chard came on strong. Sweet potatoes gave it their best shot. And blackberries brought their A game with a heavy dose of antioxidants.
But in the end, it was a humble leafy green, mostly overlooked by foodies and health influencers, that took the top spot in the US Centers for Disease Control and Prevention’s (CDC) list of the healthiest fruit or vegetable.
Based solely on nutritional density, watercress was voted the healthiest vegetable with a perfect 100 out of 100 score. The runners-up didn’t even come close, with Chinese cabbage taking the silver medal at a 92 and chard, beet greens, and spinach not quite cracking the 90s.
The CDC isn’t alone in bestowing this accolade on watercress either. Dr. Joel Fuhrman, creator of the ANDI score (which stands for Aggregate Nutrient Density Index), also gave watercress the number one spot with a perfect 1,000 out of 1,000.
Despite its low profile at present, watercress hasn’t always been such a nutritional dark horse. Historically, it was used as both food and medicine. In fact, it may be one of the first leafy vegetables consumed by humans.
Traditional and folk healers in the Middle East used watercress extensively to treat various ailments, as have communities across western Asia, India, Europe, and Africa. According to lore, it can be used to treat respiratory ailments, diabetes, digestive disorders, and possibly even heart disease and cancer.
Watercress may also be good for the environment due to its ability to absorb heavy metals and toxins from water and soil (although this ability has downsides, such as how much of those toxic chemicals can end up on your salad plate).
Let’s take a deeper look at the “world’s healthiest vegetable.”
What Is Watercress?
Watercress (or Nasturtium officinale, as botanists call it) is an aquatic or semi-aquatic herb. It’s a member of the Brassicaceae family, which also includes broccoli, kale, and Brussels sprouts.
As a cruciferous vegetable, watercress is one of the more pungent leafy greens. It’s peppery like arugula but with a milder and less bitter flavor.
Watercress grows wild near natural springs and on the banks of slow-moving streams and rivers. Amazingly, the entire watercress plant is edible: leaves, stems, roots, and flowers.
Originally from northern Europe, it is now commercially cultivated in Europe, Asia, North America, South Africa, and Australia.
Watercress Nutrition
If watercress takes the cake (shouldn’t that be “takes the salad”?) for the world’s healthiest veggie, it should have some stellar nutritional stats. And luckily, it does.
Watercress is extremely nutrient-dense, packing a huge punch of vitamins A, C, and K, minerals including calcium, copper, and manganese, and antioxidants such as polyphenols and rutin, which protect against cellular damage.
It’s also high in carotenoids such as lutein and beta-carotene, which support eye health, and glucosinolates — compounds thought to have cancer-fighting properties.
Watercress is also low in calories but high in water content, making it a hydrating, low-energy-density food that can be helpful for weight loss or weight management regimens.
The Health Benefits of Watercress
Watercress can back up its claim of nutritional excellence with some really good nutrition facts. But what about where the rubber meets the road? What’s the evidence that eating watercress improves health outcomes?
Well, for one thing, traditional healing systems have revered the plant for thousands of years. Modern science is catching up to this fact, too, albeit slowly.
Most research studies on watercress have used animal models, test tubes, or processed extracts rather than feeding people whole watercress and seeing what happens.
That said, there are still many good reasons to be hopeful about watercress’s ability to protect and improve health. Here are some of the best-supporting findings.
Watercress and Kidney Health
It makes sense that watercress can help protect your kidneys since it’s a member of the leafy greens gang, a group known for providing beneficial nutrients to those amazing filtering organs.
In 2017, researchers from Iran examined whether watercress extract could protect rats’ kidneys from the harmful side effects of a powerful antibiotic called gentamicin. (Our view on the use of animals in medical research is here.)
They divided the rats into groups, with some receiving gentamicin alone and others also receiving various doses of watercress extract. After ten days, the rats treated with watercress showed much less kidney damage and lower levels of biomarkers of oxidative stress and inflammation.
Another 2021 study from Iran explored whether watercress extract in capsule form could protect human patients undergoing kidney dialysis. Forty-six patients took either watercress extract or a placebo for four weeks. Notably, the group taking watercress showed reduced levels of harmful molecules and heightened antioxidant enzyme activity, improving the health of dialysis patients.
Watercress and Heart Health
Watercress might also be helpful when it comes to protecting your heart. In 2021, researchers looked at how watercress extract could affect the heart health of overweight people with physical disabilities. Over five weeks, 34 participants took either watercress extract or a placebo. The watercress extract significantly lowered “bad” (LDL) cholesterol. It also reduced lipid peroxidation, a process where free radicals attack lipids in cell membranes, resulting in cell damage.
What’s more, a 2016 meta-analysis of eight studies involving over 540,000 participants found that people who consumed the highest amounts of cruciferous leafy greens (including, but not limited to, watercress) had a 16% lower risk of developing heart issues.
Watercress and Bone Health
Osteoporosis, or bone loss, affects a third of all women and a fifth of all men over the age of 50. While most osteoporosis drugs focus on bone resorption (slowing down the breakdown process), watercress extract (found to contain a phytonutrient called rutin) can help your body build new bone. The mineral and vitamin K content of watercress also protect against osteoporosis.
Like other members of the brassica family, watercress contains sulfur-based compounds that can help maintain bone strength. These compounds, such as polysulfides and isothiocyanates, act as antioxidants and anti-inflammatories, protecting bone cells and supporting bone formation.
For more on osteoporosis and bone health, see our article here.
Watercress and Cancer
Watercress also shares the brassica trait of being rich in sulforaphane, one of the most powerful natural anticancer compounds ever studied.
A 2005 test-tube study found that watercress extract significantly reduced the ability of breast cancer cells to spread by limiting the activity of a protein called (get ready for some fancy-sounding chemistry words) matrix metalloproteinase-9 (MMP-9). Researchers attributed the beneficial effects to a specific type of sulforaphane called 4-methysulfinylbutyl isothiocyanate. (This will not be on the test.)
In 2022, researchers also measured the levels of glucosinolates — compounds known for their potential anticancer properties — in watercress and kale. They discovered that watercress contained two and a half times more glucosinolates than kale.
In the body, these glucosinolates turn into bioactive substances with powerful antioxidant and anticancer activities — the compounds from watercress proving particularly effective. What’s more, they target cancer cells while remaining non-toxic to normal cells, demonstrating their potential as natural, cancer-fighting foods.
Even more proof of their anticancer superpowers was found in a 2023 study where watercress flower extract killed skin cancer cells while sparing healthy skin cells. Researchers discovered that a particular compound, phenethyl isothiocyanate-enriched fraction (PhEF), triggered the cancer cells to self-destruct (a process known as apoptosis).
Watercress and DNA Damage
According to one of the most popular theories of cancer initiation, the process typically starts with damage to DNA.
A 2007 study explored the effects of eight weeks of watercress supplementation on the DNA of healthy adults, including smokers and non-smokers. This study was unusual because it asked participants to eat watercress rather than receive it as an extract in pill form.
Researchers found that consuming watercress reduced lymphocyte DNA damage and increased plasma antioxidant levels significantly (including lutein and beta-carotene). Smokers received even greater benefits than non-smokers.
A 2013 study also found that 15 days of drinking watercress juice protected mice from DNA damage caused by cyclophosphamide, a chemotherapy drug.
Watercress and Asthma
Iran’s folk medicine tradition has long credited watercress with the ability to treat asthma.
Putting this to the test, in 2024, researchers conducted a month-long, double-blind, placebo-controlled trial in which asthmatic patients took 500 mg capsules of watercress extract twice daily. Compared to those who took a placebo, the patients who took the watercress extract showed reduced levels of harmful oxidative stress markers and increased antioxidant capacity in their blood. These results suggest that watercress might be helpful in the management of asthma symptoms.
Downsides to Watercress
Watercress isn’t all bunnies and guppies, however. It does come with some potential downsides to your health and the environment.
Drug Interactions
With great power comes great responsibility. And watercress is such a nutritional powerhouse that it can interact with certain medications. Its vitamin K content may interfere with blood-thinning and anticoagulant medications like warfarin.
Watercress can also get in the way of the pain drug chlorzoxazone, enabling it to stay in the system longer before being metabolized and eliminated.
And because watercress can act as a diuretic (increasing your need to pee), it can dehydrate you, which, if you’re taking lithium, can lead to a buildup of the metal.
Risk of Contamination in Watercress
Watercress’s ability to absorb minerals from the soil is a great thing. But this same trait means that it can also absorb toxic heavy metals. A study of watercress grown on Spain’s Canary Islands found that the plant contained arsenic, cadmium, mercury, and lead.
This downside also has a potential upside. If watercress is grown specifically for its ability to absorb heavy metals and other environmental pollutants, it can be used to clean soil and waterways. In fact, watercress may be able to thrive in the presence of toxins that would damage other plants.
Researchers from Switzerland and Poland discovered that watercress has specialized genes that allow it to withstand a barrage of toxic chemicals.
Wild watercress foraging can be fun but comes with some hazards. When improperly sourced or insufficiently washed, it may also be biologically contaminated by organisms such as liver fluke, parasites, and harmful bacteria.
That’s why it’s recommended that you cook any watercress you’ve wild foraged before eating it and why hydroponic watercress may be the safest option.
Environmental Impacts of Watercress
Because watercress is such a resilient plant and can grow so quickly, it’s considered invasive in many areas. In parts of North America, Australasia, and southern Africa, the nutritional champion is considered a weed. It’s taken over waterways in some places, crowding out native plants and changing entire ecosystems.
That’s one reason that wild harvesting watercress could be a net positive contribution to an ecosystem. Before you do any significant amount of wild harvesting, though, I’d encourage you to talk to people with ecosystem expertise to be sure you are engaging thoughtfully.
Cultivated watercress comes with its own issues. The phosphate-based fertilizers used to support plant growth can contribute to the eutrophication of aquatic habitats. That nice-sounding word — eutrophication — means that too many nutrients can end up in the water, leading to algal blooms that turn the surface bright green and smother other aquatic life.
Pesticide use on cultivated watercress varies but can also be quite high. To get the plant’s benefits without so many risks, you can buy organic or even grow your own (see below).
Where Can You Buy Watercress?
Many major grocery stores — especially natural foods stores — carry conventional (potentially pesticide-contaminated) or organic watercress in their fresh produce sections. You can often find cut watercress, sometimes living watercress (with the roots intact), and watercress sprouts.
Watercress thrives in water-rich environments and can be grown at home. Some people like to use a hydroponic setup.
You can also grow watercress using methods that don’t require high-tech or large outlays of cash. Here’s a short video showing you how to grow watercress (indoors or outdoors) from the cress you buy at the store. And here’s a longer video demonstrating how you can grow watercress indoors from seed.
You might also find watercress at farmers markets and CSAs (community supported agriculture). Because so much is grown hydroponically, it’s available year-round, but production tends to peak in spring and early summer when it can also thrive outdoors.
You can also find dried and supplemental forms of watercress. If you have more fresh leaves than you can handle, you can dehydrate them to reduce food waste and make them last longer.
Editor’s Note: Starwest Botanicals sells organically grown watercress, which is available here.
How to Store Watercress
Due to its high water content, fresh watercress is highly perishable. It needs lots of water to stay fresh. You can store watercress in a jar of water (think of it as a healthy green bouquet). Alternatively, wrap a wet cloth or paper towel around the stems or root ball and place it in a produce bag. That way, it can last up to a week in the fridge.
When you’re ready to use the watercress, wash it to remove any contaminants, then rinse in a salad spinner.
(If you’re concerned about pesticide residues, find out the best ways to wash fruits and vegetables to get rid of as many pesticides as possible.)
Freezing watercress isn’t recommended unless you plan on cooking with it, as its taste and texture will change.
Using Watercress in Recipes
Watercress has a peppery flavor that can add a distinctive bite to recipes.
If you’re into Downton Abbey, you may enjoy watercress in afternoon tea sandwiches. Cucumber and cress and “eggless” egg and cress sandwiches have appeared at many such high teas.
Here’s our article about having a proper plant-based afternoon tea party; corsets and monocles are optional.
Other ways to use watercress in recipes include the following:
- Blended into cooked or chilled soups (or stews)
- Cooked with other vegetables in stir fries and grain bowls
- Used raw like other leafy greens or sprouts in sandwiches and wraps
- Sauteed as a side dish
- Cooked into hot dips
- Raw in salads
- Raw and blended into smoothies and sauces
- Cooked into frittatas and chickpea omelets
If you can’t find watercress, you can substitute arugula, radish sprouts, mustard greens, or dandelion greens, depending on what’s available and your tolerance for that peppery “bite.”
Watercress Recipes
Get ready to add a burst of freshness and flavor to your meals with these three plant-based watercress recipes! With its signature peppery taste and impressive nutritional content, watercress elevates any dish.
Whether you’re craving a hearty sandwich, a crisp salad, or a nourishing soup, these watercress recipes showcase the versatility of this leafy green in a way that will have you excited to try it!
1. Autumn Orchard Watercress Salad With Sweet Mustard Dressing
Autumn Orchard Watercress Salad With Sweet Mustard Dressing is a delicious way to enhance your plant-based nutrition! Watercress is a powerhouse green, packed with vitamins A, C, and K, and known for its immune-building and anti-inflammatory properties. Paired with sweet potatoes, crisp organic apples, crunchy walnuts, and radishes, this salad is as nourishing as it is flavorful. The natural sweetness from cranberries complements the peppery watercress, while the Sweet Mustard Dressing ties it all together, making this a colorful and flavorful dish.
2. Creamy Edamame and Watercress Soup
This Creamy Edamame and Watercress Soup is a vibrant, nutrient-packed meal that’s as tasty as it is good for you! Watercress, one of the most nutrient-dense greens, is fantastic for heart health and has anti-cancer properties. Paired with protein-rich edamame, it’s the perfect plant-based dish to fuel your body.
The smooth combination of onion, celery, potatoes, and vegetable broth creates a creamy, comforting base, while the peppery watercress brings a burst of freshness. Finish it off with some Garlic Cashew Cream, Vegan Walnut Parmesan, and crunchy pumpkin seeds for that extra layer of flavor and texture!
3. Creamy and Crunchy Blackened Tempeh Tower Sandwich
This Creamy and Crunchy Blackened Tempeh Tower Sandwich is not only delicious but also packed with nutrition, thanks to a featured ingredient: watercress! Watercress adds a fresh, peppery crunch and pairs well with the smoky, grilled tempeh, creamy avocado, and tangy pickled red onions. This sandwich delivers a satisfying balance of flavors and textures. Enjoy it with a Spicy Mustard Dipping Sauce for a nutrient-rich meal that’s as good for you as it tastes!
(Water)Cress Is Best!
With its rich array of vitamins, minerals, antioxidants, and compounds like glucosinolates and rutin, watercress offers a multitude of health benefits. From supporting heart health to promoting bone strength and potentially reducing cancer risk, this humble leafy green deserves a prominent place in our diets.
As with any food, however, it’s important to be mindful of potential downsides. By sourcing it carefully and consuming it in moderation, the risks can be minimized, allowing more people to enjoy its robust health benefits.
However you eat it, watercress is a versatile addition to any meal. Its peppery flavor and vibrant green hue enhance the taste and appearance of dishes and provide a burst of nutrition with every bite.
Featured Image: iStock.com/Lena_Zajchikova
Read Next:
- Why Is Kale Good for You? The Top Benefits of This True Superfood
What Is Sulforaphane — And Why Is It So Good for You?