You have a wide range of vegetables to choose from on a regular basis, but research shows that there’s one that’s particularly good for you: watercress.
This leafy green has been deemed the healthiest vegetable by the Centers for Disease Control and Prevention (CDC), with an impressive nutrient density score of 100 out of 100. But watercress isn’t just ranked the healthiest vegetable: It beat runner-up Chinese cabbage by more than eight points.
Nutritionists aren’t shocked. “I can believe that watercress is the ‘healthiest’ vegetable,” says Dana Ellis Hunnes, Ph.D., a senior dietitian at UCLA Medical Center and assistant professor at the UCLA Fielding School of Public Health. Among other things, Hunnes points out that this is a “nutrient-dense” food.
Given that watercress isn’t a staple in most American fridges, it’s understandable to have questions. Here’s why this vegetable is so healthy, plus how to get more of it on your plate.
What is watercress and what makes it so healthy?
Watercress is a type of cruciferous vegetable that belongs in the same family as kale, broccoli, Chinese cabbage, arugula, and Brussels sprouts, says Rachel O’Connor, R.D., C.D.N., a dietitian at NewYork-Presbyterian/Columbia University Irving Medical Center. It’s also an aquatic flowering plant (hence, the name) and grows in shallow water or damp soil, Hunnes says.
Watercress got top honors thanks to its perfect nutrient density score. “Nutrient density is the ratio of nutrients in a food to the amount of energy — or calories — it provides,” O’Connor says. “A nutrient density score is essentially a numeric value given to rate how nutritious certain foods are.” The more nutrient-dense a food is, the more vitamins, minerals, and antioxidants it has per calorie per gram, Hunnes explains.
Watercress has a few compounds, including 3,3′-diindolylmethane (DIM) and sulforaphane, which have been linked to a lower risk of cancer, O’Connor says. The vegetable is also rich in vitamin K. While watercress contains fiber, the levels of the nutrient aren’t as high as they are in some fellow cruciferous vegetables. One cup of cooked broccoli, for example, will provide around 5 grams of fiber, while one cup of watercress provides less than 1 gram. “Fiber is an important component to our diets for numerous reasons, so watercress should definitely not be the only cruciferous vegetable one eats,” O’Connor says.
Do any other vegetables come close?
The CDC’s study lists out more than 40 so-called “powerhouse” fruits and vegetables. While watercress was the only one that received a perfect score, the runners-up are also worth noting. Those include:
- Chinese cabbage (91.99 points)
- Swiss chard (89.27 points)
- Beetroot (87.08 points)
- Spinach (86.43 points)
How much watercress do you need to eat?
It is generally recommended that you have four to five servings of fruits and vegetables a day, and four to five servings of cruciferous vegetables a week. But you can have watercress as much as you’d like, Hunnes says. “You could eat one cupful at a time,” she says. “You could eat it more often or less often, too.”
While you can cook watercress, it may be better to have it raw to reap the full benefits. “Watercress, like other vegetables, loses some vitamin C and B vitamins when cooked,” O’Connor says. “Vitamin C is water-soluble and sensitive to heat, and it can leach out of vegetables when they are exposed to hot water. B vitamins are similarly heat-sensitive.” So, use it as a base for salads, toss it in a sandwich, or sprinkle it on top of a stir fry for added nutrition.
No matter how you prepare it, Hunnes stresses that you should have more than just watercress. “Even if it is the healthiest of all vegetables, it’s still better to eat a wide range of vegetables and fruits than to just stick with one,” she says. “That allows you to get a fuller complement of nutrients.”