Watercress: Why It Tops the CDC’s Nutrient Density List + Benefits for Longevity & Beyond

October 27, 2025

Watercress is a cruciferous vegetable that is so good for you that the Centers for Disease Control and Prevention (CDC) actually classifies it as a “powerhouse” vegetable and the healthiest vegetable on the planet.

This cousin of kale has a long history as a deliciously nutritious herb and natural remedy for many ailments. Plus, it’s also often served in salads, added to sandwiches and enjoyed as a lightly steamed side dish.

Why exactly does the CDC consider it such a healthy food? Not only does research show that this nutritious cruciferous vegetable may be associated with a reduced risk of cancer, but it could also help lower blood pressure, fight inflammation, support bone health and more.

What is watercress?

Watercress is a perennial vegetable that grows naturally along running waterways, thriving in both the sun and water. This leafy green does especially well in varying soil conditions, as long as the soils stay saturated with water.

The leaves and shoots are cultivated for their culinary and medicinal uses.

While the flavor is best during the cooler parts of the year, watercress can withstand harvest throughout the winter. However, once it blooms, the flavor of watercress typically declines.

Watercress is closely related to other cruciferous vegetables, such as broccoli, cabbage and kale. It’s also widely available and can be found in the produce section of most supermarkets alongside other vegetables.

Keep in mind that it’s important to wash thoroughly before cooking or consuming because it may contain harmful parasites and pathogens due to its growth in nearby stagnant waters.

Watercress benefits

Thanks to its impressive nutrient profile, watercress has been linked to a number of health benefits. In fact, adding this leafy green to your diet can help protect against disease, fight inflammation and promote better health.

1. May help reduce risk of colon cancer and other cancers

As a leafy green vegetable and cruciferous veggie, watercress has secured its slot on the list of cancer-fighting foods. This is because it’s rich in vitamins, minerals and antioxidants, yet very low in calories, fat, carbs and sodium.

It also contains beneficial compounds, such as isothiocyanates, which are naturally occurring chemicals found in many cruciferous vegetables. Promising research shows that these compounds could possess powerful cancer-fighting properties and may even help block the growth and spread of cancer cells.

Further studies have noted that these compounds, when broken down, may help protect cells from DNA damage by inactivating carcinogens. These findings suggest this vegetable, along with other cruciferous veggies, may help prevent and fight other forms of cancer as well, including liver, lung and breast cancer.

2. Contains useful omega-3s

Most of us are familiar with omega-3 foods such as salmon, tuna and mackerel. However, did you know that you can get your fix of these heart-healthy fats by upping your intake of leafy greens as well?

While watercress contains a variety of phytonutrients, vitamins and minerals, it also contains a relatively high proportion of omega-3 polyunsaturated fatty acids (PUFAs), mainly in the form of alpha-linolenic acid.

A study was conducted by the Department of Food Science at RMIT University in Australia to help determine the fatty acid content of 11 green vegetables. Interestingly enough, the total fatty acid concentrations of the vegetables in the study ranged from 44 milligrams per 100 grams wet weight in Chinese cabbage to 372 milligrams per 100 grams in watercress.

Although alpha-linolenic acid must be converted into active forms of omega-3 fatty acids, including eicosapentaenoic acid and docosahexaenoic acid, adding this leafy green to your daily diet can be an effective strategy to boost your intake of omega-3 fatty acids and protect against heart disease if you don’t regularly consume fish.

3. Provides beneficial anti-inflammatory effects

Cruciferous vegetables are anti-inflammatory foods that contain antiviral and antibacterial effects that can help reduce inflammation. In fact, in a randomized, crossover intervention involving 19 healthy young adults, consumption of 85 grams of fresh watercress followed by a high-intensity exercise bout revealed intriguing immune-modulating effects.

After the workout, while there was an expected rise in pro-inflammatory cytokines, such as IL-6 and TNF-alpha, participants who ate watercress exhibited a stronger subsequent downregulation of these same markers during the recovery phase compared to the control meal. This suggests that this veggie supports the body’s transition from inflammation to recovery, promoting a quicker resolution of the inflammatory response rather than simply suppressing it outright.

The authors proposed that the glucosinolate gluconasturtiin (and its breakdown product phenethyl isothiocyanate) may underlie this anti-inflammatory modulation.

Watercress is also loaded with antioxidants, which can help neutralize harmful free radicals to fight inflammation at a cellular level. These antioxidants play a key role in maintaining immune function, enhancing eye health, promoting better blood sugar control and more.

4. Helps balance blood pressure

Minerals such as calcium, magnesium and potassium all play a central role in regulating blood pressure levels. This healthy green is a great source of both calcium and magnesium and could potentially help lower blood pressure levels.

According to a study conducted by the King’s College London British Heart Foundation Centre, watercress and similar foods have been shown to benefit the health of the blood vessels and may help reduce blood pressure, block platelet aggregation and even improve endothelial dysfunction to protect against heart disease.

5. Supports healthy skin, hair and nails

The phytonutrients found in foods like watercress can bring big benefits when it comes to the health of your hair, skin and nails.

This is because superfoods like this are loaded with nutrients like calcium, magnesium and potassium, all of which are crucial to the health of your hair, skin and nails. Thanks to its high water content, watercress can also promote proper hydration.

6. Strengthens bones and teeth

Although dairy is one of the most well-known sources of calcium, leafy greens also provide a hearty dose of calcium in each serving. In addition to supplying a good amount of calcium, watercress is also a good source of magnesium and vitamin K, both of which can help maintain strong, healthy bones.

Calcium can aid in the prevention of osteoporosis, which is a disease caused by a gradual loss in bone density. Meanwhile, vitamin K can help maintain calcium stores in the bone to maintain bone strength, and magnesium impacts the formation of bone cells.

7. Helps enhance immunity

Watercress is loaded with immune-boosting nutrients like vitamin C, vitamin A and zinc. These antioxidants help strengthen the body’s natural defenses, supporting white blood cell activity and reducing oxidative stress that can weaken immunity.

Regularly consuming it may help your body better fend off infections and seasonal illnesses.

8. Can support healthy weight management

Low in calories yet rich in nutrients, watercress makes an excellent addition to a balanced diet for healthy weight management. Its high water and fiber content help increase satiety and reduce overall calorie intake.

Meanwhile, its nutrient density ensures you’re fueling your body with essential vitamins and minerals without excess calories.

9. May boost athletic performance

Because it’s rich in nitrates, watercress may enhance athletic performance by improving blood flow and oxygen delivery to muscles. Some studies suggest nitrate-rich vegetables like watercress can improve endurance and reduce fatigue during physical activity.

Its antioxidants may also support faster recovery after exercise.

In a randomized, controlled trial of 10 healthy young men (mean age about 23 years old) published in the British Journal of Nutrition, participants consumed either a single portion (85 grams) of watercress two hours before an exhaustive treadmill exercise test (acute phase) or ingested it daily for eight weeks (chronic phase) before the same exercise protocol. After the exhaustive exercise, markers of oxidative stress rose significantly in the control (no watercress) phases.

Meanwhile, both acute and chronic watercress intake attenuated these increases: DNA damage and lipid peroxidation were significantly lower in the watercress conditions compared to control. The study also found that ingestion of this leafy green elevated blood concentrations of lipid-soluble antioxidant nutrients, which likely contributed to the protective effect.

The attenuation of exercise-induced oxidative damage suggests that this veggie might help mitigate the physiological stress of intense exercise, which could in turn support improved recovery and potentially performance over time.

10. Protects eye health

Watercress contains key carotenoids like beta-carotene, lutein and zeaxanthin, which are known to protect the eyes from oxidative damage and support healthy vision. These compounds help filter harmful blue light and may lower the risk of age-related macular degeneration and cataracts over time.

In fact, a randomized, controlled trial published in the American Journal of Clinical Nutrition found that consuming 85 grams of raw watercress daily for eight weeks increased blood levels of the lutein (100 percent increase) and beta-carotene (33 percent increase) in study participants.

11. May aid mental health

The high antioxidant and folate content in watercress may positively impact mood and cognitive health. Folate plays a key role in the production of neurotransmitters like serotonin and dopamine, which regulate mood and emotional balance.

Antioxidants in watercress may also protect brain cells from oxidative stress, supporting long-term brain health.

12. Supports kidney and liver health

Watercress acts as a natural diuretic, helping the body flush out excess fluids and waste through the kidneys. It provides minerals like potassium and magnesium that can support healthy kidney function and electrolyte balance.

In traditional medicine, watercress has long been used to promote kidney cleansing and urinary tract health.

13. Could benefit asthmatics

Some evidence suggests that this leafy green may help reduce inflammation in the respiratory tract, potentially benefiting individuals with asthma. Its antioxidant and anti-inflammatory compounds can help soothe airways and support easier breathing, particularly when combined with an overall anti-inflammatory diet.

In a randomized, double-blind, placebo-controlled human trial, adults aged 18-65 with asthma were given 500-milligram capsules of a hydroalcoholic extract of watercress twice daily for four weeks. The study found that, compared with placebo, the watercress-extract group exhibited significant reductions in oxidative-stress markers and an increase in overall antioxidant capacity (measured by ferric reducing antioxidant power).

The authors suggested that these changes indicate the extract may help improve oxidative burden in asthma patients, which could support airway health, although they noted further studies are needed to confirm clinical improvements in asthma control.

14. May combat diabetes

Watercress may help stabilize blood sugar levels thanks to its fiber, antioxidants and alpha-lipoic acid content. These compounds can support healthy insulin sensitivity and reduce oxidative stress associated with diabetes.

Including this vegetable in a balanced diet may contribute to better metabolic and blood sugar control.

15. Promotes heart health

Rich in nitrates, potassium and antioxidants, watercress supports cardiovascular health in several ways. It helps promote healthy blood pressure, improve blood vessel function and reduce inflammation linked to heart disease.

Its nutrient profile makes it a valuable addition to any heart-healthy diet.

Nutrition facts

A one-cup serving of raw watercress (about 34 grams) contains approximately:

Calories: 3.7
Total Carbohydrates: .4 g
Fiber: 0.2 g
Sugar: 0.1 g
Total Fat: 0.03 g
Saturated Fat: 0.01 g
Polyunsaturated Fat: 0.01 g
Monounsaturated Fat: 0.003 g
Protein: 0.8 g
Sodium: 13.9 mg (<1% DV*)
Vitamin K: 85 mcg (71% DV)
Vitamin C: 14.6 mg (16% DV)
Vitamin A: 54.4 mcg (6% DV)
Manganese: 0.1 mg (4% DV)
Calcium: 40.8 mg (3% DV)
Copper: 0.03 mg (3% DV)
Thiamine: 0.03 mg (3% DV)
Riboflavin: 0.04 mg (3% DV)

*Daily Value: Percentages are based on a diet of 2,000 calories a day.

Each serving also contains 7.8 milligrams omega-3 fatty acids and 4.1 milligrams omega-6 fatty acids, along with some iron, magnesium, phosphorus, potassium, zinc, selenium, niacin, pantothenic acid, vitamin B6, folate, choline, beta-carotene, vitamin E, .

Watercress vs. kale

Watercress and kale are both powerhouses when it comes to nutrition. In fact, it’s been reported that watercress may rival several other superfoods in terms of its nutrient content, including Chinese cabbage, Swiss chard, beet greens, spinach and chicory root.

Though kale may still reign as a superstar ingredient, watercress upholds the top spot in terms of nutrient density. According to a review published in Preventing Chronic Disease, it ranks even higher than kale, earning double the score of kale for its nutrient density.

Here’s a closer look at how these two veggies measure up:

Watercress

High in antioxidants, which can reduce inflammation and cell damage
Lower in calories and some nutrients than kale
Great source of vitamin K, which is good for blood clotting and bones
High in vitamin A, which improves immune function and vision
Rich in vitamin C, a water-soluble nutrient that helps heal wounds and forms collagen
Loaded with calcium, which is essential for muscle and nerve function along with bone health

Kale

High in vitamins A, K and C
Good source of folate, which helps create new cells and prevents birth defects
Rich in iron, which is necessary for red blood cell formation
Contains magnesium, which is important for the immune system, heart health and blood sugar control

Interesting facts

Typically cultivated in pure spring water, watercress has been labeled as a superfood for centuries.

Hippocrates was known to locate his first hospital near a stream, where watercress grows best, so his patients could be treated with it, and Greek soldiers were given watercress as a blood-cleansing tonic before going into battle.

With its tangy, peppery powerhouse of nutrients, there are many options for how to eat watercress, and it’s an especially great choice for dishes such as soups, salads and casseroles.

In the 1800s, watercress sandwiches were a staple in the diets of the working class. The veggie was most often eaten for breakfast as a watercress sandwich in Hampshire and Dorset in the United Kingdom, mostly because it was easily accessible and could be picked free from rivers and streams where it grew wild. If people were too poor to buy bread for their sandwiches, they ate it on its own, making it known as the “poor man’s bread.”

Traditionally grown watercress is green and has a distinctive peppery, mustard-like flavor. It became known as a commercial crop in England around 1808, favored for both its flavor and nutrient density.

In 1865, the Georgian town of Arlesford became the center of the watercress industry and so popular that a railway line, named the Watercress Line, was established as a route to London.

The health benefits became evident, making it in great demand and ultimately leading to commercial watercress farms throughout Hampshire. Unfortunately, during the 1960s, the Watercress Railway Line was closed, leaving the roadways as the only option for transporting it, and 90 percent of growers left the industry by the 1980s.

The heritage railway, still known as the Watercress Line, runs from New Alresford to Alton and now features a footbridge at London’s King’s Cross station that was in the Harry Potter films.

How to add to diet (recipes)

Wondering where to buy watercress? This delicious veggie is widely available at most grocery stores and farmers markets, right alongside other leafy greens like spinach and kale.

If you have a few watercress seeds, you can also opt to grow it at home. There are plenty of online guides for how to grow watercress, even without access to your own river or pond.

Watercress is spicier than spinach given its mustard background. It’s great in salads either alone or as a blend with other greens.

It can also add a zing of flavor to sandwiches and can be pureed and added to soups for a touch of extra spice. It even goes well with melons, nuts, potatoes, sweet potatoes, beets, leeks and corn.

You can also try breaking out the juicer and whipping up a glass of watercress juice. With its mild and refreshing watercress taste, it works especially well paired with fruits such as kiwi, apples or pineapple.

Here are a few other watercress recipes that you can experiment with:

Risks and side effects

Cruciferous vegetables are classified as goitrogens, which are compounds that can interfere with the production of thyroid hormones when consumed in high amounts. While most research indicates that these vegetables can be enjoyed as part of a healthy diet by those with thyroid issues, it’s best to keep your intake in moderation to reduce the risk of adverse effects on health.

Although it is generally well-tolerated by most healthy adults, it may trigger side effects like stomach pain, gas and bloating in some people. If you experience any adverse side effects, consider decreasing your intake and consulting with your doctor if symptoms persist.

Frequently asked questions

Is watercress OK for the kidneys?

Yes, watercress is generally beneficial for kidney health. Its natural diuretic properties can help the body flush out toxins and excess fluid through the kidneys. However, people with chronic kidney disease or those advised to limit potassium intake should speak with their healthcare providers before consuming large quantities, as watercress is naturally high in potassium.

Can you eat watercress every day?

Yes, watercress can be safely eaten daily as part of a balanced diet. It’s nutrient-dense yet low in calories, offering an excellent source of vitamins A, C and K, along with antioxidants and phytonutrients that promote overall wellness. Eating a handful of fresh watercress regularly can help support immune function, bone strength and heart health.

What are the side effects of watercress?

Watercress is safe for most people when eaten in normal food amounts, but consuming very large amounts could cause digestive discomfort or interact with certain medications, such as blood thinners, due to its high vitamin K content. Always wash fresh watercress thoroughly before eating to remove any bacteria or residue.

Can watercress help with high blood pressure?

Yes. Watercress contains nitrates, potassium and antioxidants that support healthy blood vessel function and circulation, which can help regulate blood pressure. Including watercress in a heart-healthy diet rich in vegetables, fruits and healthy fats may naturally support cardiovascular wellness.

Is watercress good for the liver?

Watercress supports natural detoxification processes in the body, including liver function. It provides antioxidants and sulfur-containing compounds that help neutralize toxins and support healthy liver enzyme activity. Some research suggests that cruciferous vegetables like watercress may help protect liver cells from oxidative damage.

Can you eat raw watercress?

Absolutely. Watercress is commonly eaten raw in salads, sandwiches or smoothies. Raw watercress retains its full vitamin C, enzyme and antioxidant content, making it one of the most nutrient-rich leafy greens you can eat fresh.

Just be sure to rinse it well before consumption.

Does watercress help with digestion?

Yes, the fiber and phytonutrients in watercress can support healthy digestion. It helps stimulate bile flow, which aids in fat breakdown, and promotes the growth of beneficial gut bacteria. Its mild bitterness can also support appetite and digestive enzyme production.

Is watercress a superfood?

Watercress is often considered a true superfood because of its exceptional nutrient density. It consistently ranks at the top of the CDC’s list of powerhouse fruits and vegetables, meaning it provides the highest nutrient content per calorie of any food tested.

What’s the best way to eat watercress?

Watercress can be enjoyed raw in salads and sandwiches, lightly sautéed, blended into soups, or added to smoothies for a peppery, nutrient-packed boost. Avoid overcooking it, as heat can reduce its vitamin C and antioxidant levels.

Final thoughts

Watercress is a leafy green, cruciferous vegetable that is known for its powerful health-promoting properties.
The watercress nutrition profile is low in calories yet high in fiber and vitamins A, K and C.
It’s been linked to a number of health benefits and could potentially help protect against certain types of cancer, reduce blood pressure, decrease inflammation and promote bone health. Plus, thanks to its content of phytonutrients, there may also be watercress benefits for the hair, skin and nails.
Apart from the many watercress benefits and side effects, it’s also versatile, delicious and easy to enjoy in a variety of different recipes.
In fact, there are a number of different options for eating watercress, and it makes a great addition to soups, salads, stir-fries and sandwiches.

Watercress: Why It Tops the CDC’s Nutrient Density List + Benefits for Longevity & Beyond

What is watercress?