Which is Healthier, Watercress or Spinach? A Comprehensive Nutritional Comparison

December 12, 2025 •

4 min read

According to the CDC, watercress received a perfect nutrient-density score of 100, outranking spinach which scored 86.43. The question of which is healthier, watercress or spinach, however, involves more than just a single score.

Quick Summary

This article provides a detailed nutritional comparison of watercress and spinach, examining their key vitamins, minerals, and unique health benefits to determine which green offers the most value for different health goals.

Key Points

Nutrient Density: Watercress is officially the most nutrient-dense vegetable according to the CDC, scoring a perfect 100, while spinach is also very high with a score of 86.43.
Calcium Absorption: Watercress has lower oxalate levels than spinach, which means your body can absorb its calcium more effectively, despite spinach sometimes containing more total calcium.
Cancer-Fighting Compounds: Watercress contains unique isothiocyanates that have been shown to inhibit cancer cell growth and protect against DNA damage.
Eye Health Boosters: Both greens are excellent for eye health due to antioxidants like lutein and beta-carotene, with spinach being a particularly rich source of lutein and zeaxanthin.
Considerations for Medication: Individuals taking blood-thinning medication must monitor their intake of high-Vitamin K foods like watercress to maintain consistent levels.
Oxalate Levels: The high oxalate content in spinach can be a concern for those prone to kidney stones and can interfere with mineral absorption.
Flavor and Culinary Use: Watercress offers a peppery taste great for raw dishes, while spinach has a milder flavor and is highly versatile, whether raw or cooked.

Both watercress and spinach are titans in the world of leafy greens, each celebrated for its unique nutritional profile. While both are excellent additions to a healthy diet, their specific strengths and weaknesses can inform which one is the better choice for your personal health goals. A closer look at their nutritional composition, health benefits, and potential drawbacks reveals a compelling comparison.

The Verdict: Nutrient Density Crowned

The Centers for Disease Control and Prevention (CDC) released a list of "powerhouse fruits and vegetables" and famously ranked watercress at the top with a perfect 100. Spinach, while highly ranked, came in with a score of 86.43. This ranking is based on a food's nutrient density, which measures the concentration of 17 key nutrients per calorie. Watercress’s perfect score highlights its exceptional nutrient-to-calorie ratio, making it a powerful choice for maximum nutritional benefit with minimal caloric impact.

Nutritional Breakdown: Watercress vs. Spinach

To understand why watercress is so highly rated, it's essential to break down the specific nutritional differences between the two greens.

Vitamins: Watercress provides over 100% of the daily recommended value for Vitamin K in just one cup, and is notably rich in Vitamin C and Vitamin A. Spinach is also high in these vitamins but contains significantly more folate (Vitamin B9) per cup than watercress. However, some vitamins, like C, can be lost in cooking, making raw consumption of watercress particularly beneficial.
Minerals: Watercress boasts higher levels of bioavailable calcium than spinach. The reason for this lies in the high oxalate content of spinach, which binds to calcium and other minerals like iron and magnesium, reducing their absorption. Watercress, being a low-oxalate vegetable, offers a distinct advantage for those seeking better mineral bioavailability.
Unique Compounds: Watercress is a cruciferous vegetable rich in phytochemicals called glucosinolates. When chewed, these convert into isothiocyanates, compounds linked to powerful anti-cancer effects. Spinach is not a cruciferous vegetable but contains its own suite of beneficial compounds, including high amounts of the antioxidants lutein and zeaxanthin, both known for supporting eye health.

Health Benefits: Beyond the Numbers

While nutritional stats are important, the health outcomes are what truly matter. Here's a look at how each green contributes to overall wellness.

Cancer Prevention: Studies show that watercress's isothiocyanates can inhibit cancer cell growth and reduce DNA damage. Spinach also contains antioxidants that help fight cancer.
Bone Health: Both are great sources of Vitamin K and calcium, which are vital for strong bones. However, the higher bioavailability of calcium in watercress due to its low oxalate content gives it an edge.
Heart Health: Both greens can support cardiovascular health. The nitrates and potassium in spinach help lower blood pressure, while the antioxidants in watercress combat inflammation and oxidative stress associated with heart disease.
Eye Health: Both vegetables are rich in antioxidants that protect eye health. Spinach's high content of lutein and zeaxanthin has been linked to a reduced risk of age-related eye diseases.

Weighing the Downsides

Both watercress and spinach are generally safe, but there are a few considerations based on their nutrient composition.

For spinach, the main drawback is the high oxalate content. This can contribute to kidney stone formation in susceptible individuals and reduce the absorption of minerals like calcium and iron. Cooking can help reduce oxalate levels, but it also diminishes other nutrients like Vitamin C.
For watercress, the primary caution is for those on blood-thinning medication. The high concentration of Vitamin K, which is essential for blood clotting, requires consistent intake and careful monitoring to avoid interfering with medication efficacy.

Which Green for Your Needs?

Choosing between watercress and spinach doesn't mean you can only have one. A varied diet is the best approach, but here are some scenarios where one might be preferable:

If you are looking for the most nutrient bang for your calorie buck, watercress is the clear winner, especially when consumed raw to preserve Vitamin C.
If you are concerned about kidney stones, watercress is the better choice due to its low oxalate levels.
If you are aiming for higher folate intake, spinach offers a higher concentration.
If you prioritize better calcium absorption from a plant source, watercress's low oxalate content makes it a superior option.

A Quick Comparison Table


Feature	Watercress	Spinach
Nutrient Density (CDC Score)	100 (Perfect)	86.43 (High)
Calories (per cup, raw)	4 calories	7 calories
Vitamin K	Extremely high (106% DV)	Very high (402% DV per 100g)
Calcium Bioavailability	High (low oxalate)	Low (high oxalate)
Key Antioxidants	Isothiocyanates, Beta-carotene, Lutein	Lutein, Zeaxanthin, Quercetin
Notable Drawbacks	High Vitamin K can affect blood thinners	High oxalates can impact kidney stone sufferers

How to Incorporate These Leafy Greens Into Your Diet

Regardless of which green you favor, adding them to your diet is simple. Variety is always the best strategy for reaping a wide range of nutritional benefits.

Watercress Ideas
- Add a handful to salads for a peppery kick.
- Blend into a pesto or add to smoothies.
- Stir into soups near the end of cooking.
Spinach Ideas
- Use as a base for salads or wilt into hot dishes.
- Mix into pasta sauces, omelets, or smoothies.
- Use as a vegetable side sautéed with garlic and olive oil.

Conclusion

While watercress may hold the technical title of 'most nutrient-dense vegetable,' that doesn't make spinach a poor choice. Both are exceptionally healthy, providing a wealth of vitamins, minerals, and antioxidants that support overall health. Watercress's unique anti-cancer compounds and higher calcium bioavailability offer notable advantages, whereas spinach remains a fantastic source of folate and is more widely available. The best approach is not to choose just one, but to enjoy a mix of both to gain the fullest spectrum of nutritional benefits these powerful leafy greens have to offer.

For more information on the therapeutic properties of watercress, see this scientific review: A Narrative Review on Therapeutic Potentials of Watercress in Human Disorders.

Frequently Asked Questions

Yes, based on the CDC's nutrient-density score, watercress is more nutrient-dense per calorie. However, spinach is still an exceptionally healthy vegetable, and the 'better' option depends on your specific nutritional needs and health considerations.

Yes, some nutrients are affected by cooking. Watercress loses some Vitamin C when cooked, so eating it raw is recommended for maximum intake. Cooking spinach can reduce its oxalate content, improving mineral absorption, but can also reduce some vitamin levels.

Yes, watercress can often be used as a substitute for spinach. However, be mindful of its distinct peppery flavor, which is more pronounced than spinach's milder taste and might change the dish's profile.

Watercress has a very high Vitamin K content, which plays a critical role in blood clotting. Individuals on blood thinners like warfarin must maintain a consistent Vitamin K intake and should consult a doctor before significantly changing their consumption of watercress.

Spinach is high in oxalates, which can bind with calcium and may contribute to the formation of kidney stones in individuals who are susceptible. If you have a history of kidney stones, it's wise to moderate your intake or consult a healthcare provider.

To maximize non-heme iron absorption from spinach, pair it with a food high in Vitamin C, such as a squeeze of lemon juice, strawberries, or red peppers.

Both are excellent sources of Vitamin K, calcium, and magnesium. However, watercress's low oxalate content allows for better absorption of its calcium, giving it a slight advantage for bone health.

Watercress is rich in glucosinolates, which convert into potent anti-cancer compounds called isothiocyanates upon chewing. These compounds have been studied for their ability to inhibit cancer cell growth and reduce DNA damage.