What Are Cruciferous Vegetables — and Why Are They So Good for You?

If you’re looking for vegetables that are rich in vitamins, minerals and even have anti-cancer properties, look no further than the group known as cruciferous vegetables.

This group of leafy greens, cabbages and mustard-like veggies pack a nutritional punch and some seriously versatile flavors.

“Cruciferous vegetables are easy to find in most places and are some of the most nutrient-rich veggies around,” says registered dietitian Amber Sommer, RD, LD.

What makes crucifers so healthy? And how can you make sure you’re getting enough of them to reap their benefits? Sommer walks us through it.

What are cruciferous vegetables?

Cruciferous vegetables belong to the genus Brassica. They’re called cruciferous because their four-petaled flowers look like a crucifix, or a cross. And their rich colors are an indication of just how nutrient-packed they are.

“A good rule of thumb for greens or any fruits or vegetables is that the deeper the color, the more nutrient-dense it is. For example, spinach contains more vitamins and minerals than iceberg lettuce,” Sommer explains.

Cruciferous vegetables include some of your favorite go-to dark, leafy greens and other colorful, nutrient-rich veggies. Among the members of the cruciferous family are:

• Arugula (also called rocket).
• Bok choy.
• Broccoli.
• Brussels sprouts.
• Cabbage.
• Cauliflower.
• Collard and mustard greens.
• Daikon radish.
• Horseradish.
• Kale.
• Kohlrabi.
• Radish.
• Rapini (broccoli rabi).
• Rutabaga.
• Turnip.
• Wasabi.
• Watercress.

Health benefits

Being in the same genus means cruciferous veggies have a lot of similar characteristics.

For example, dogs belong to the same genus as wolves. Closely related, but with some important differences. More like first cousins than siblings.

“As a group, cruciferous vegetables all offer similar health benefits. I wouldn’t say any one is ‘better’ than the others. They each have a unique composition, so the key is to include a variety in your diet.” Sommer says.

She helps explain the benefits:

1. Cancer protection

Cruciferous vegetables are a rich source of compounds known as glucosinolates, which may help fight cancer.

A number of research studies suggest that a diet rich in cruciferous vegetables may lower rates of a variety of cancers, including breast, pancreatic, bladder, lung, prostate and colon cancer.

Sommer says crucifers may also help to counteract cancer-causing nitrosamines and polycyclic aromatic hydrocarbons that are found in charred, cured or barbecued fish or meats.

2. Fiber

Fiber is famous for keeping you, er … regular. It also stabilizes blood sugar, lowers cholesterol and keeps you fuller for longer. And cruciferous vegetables have high levels of both soluble and insoluble fiber. Insoluble fiber supports healthy gut bacteria. Insoluble fiber helps soften and bulk up your stool.

Broccoli in particular is a good source of fiber. One cup of broccoli gets you 5 of the recommended 25 to 35 grams of fiber you should have per day.

3. Vitamin C

Vitamin C is well-known for its immune-boosting and wound-healing properties. It also helps protect your eyes, improves iron absorption and promotes healthy skin.

And while oranges tend to get all the glory when it comes to vitamin C, leafy greens are a solid source, too.

It’s recommended that you get between 75 and 90 milligrams (mg) of vitamin C per day. These foods can help get you there:

• Broccoli (1 cup, chopped): 80 mg.
• Brussels sprouts (1 cup): 75 mg.
• Red cabbage (1 cup): 50 mg.
• Cauliflower (1 cup, chopped): 50 mg.

4. Vitamin K

Vitamin K is a powerhouse that promotes bone growth and proper blood clotting. And cruciferous vegetables are some of the best sources of vitamin K.

For example, half a cup of collard greens, frozen or boiled, contains 530 micrograms (mcg) of vitamin K. That’s more than four times the recommended vitamin K intake for a day.

5. Vitamin B9 (folate)

Vitamin B9 (folate) is important for forming red blood cells and DNA. It’s particularly important for people who are pregnant because it can help reduce the chance of birth defects. That’s why it’s a main ingredient in prenatal vitamins.

Vitamin B9 moves through your system quickly, so it’s an important vitamin to consume regularly. The U.S. Food and Drug Administration (FDA) recommends adults and children over the age of 4 get 400 mcg of folate per day.

These cruciferous veggies can help you get your fill:

• Broccoli (1/2 cup, cooked): 84 mcg.
• Turnip greens (1/2 cup, cooked): 85 mcg.
• Brussels sprouts (1/2 cup, cooked): 42 mcg.

Who should be careful with cruciferous vegetables?

Most people can enjoy cruciferous veggies without any negative consequences. But others may be advised to watch their intake.

In large amounts, cruciferous vegetables can cause gas or bloating for some people.

And people who take blood-thinning medication like warfarin (Coumadin®), may need to limit their intake. That’s because some cruciferous vegetables — particularly collard greens, kale and broccoli — are high in vitamin K, which can have a blood-clotting effect.

Additionally, some people will say that if you’ve been diagnosed with hypothyroidism (underactive thyroid), you should limit or avoid cruciferous vegetables. But Sommer says there’s little evidence that normal consumption of cruciferous vegetables affects thyroid function.

If you think you have reason to limit your intake, talk with a healthcare provider, like a primary care doctor or dietitian, about your concerns.

How much do you need?

Unless you have a health condition that says otherwise, most people are well-advised to get about 2.5 cups of veggies each day. That includes cruciferous vegetables and others.

“One cup of cooked or raw broccoli is one serving,” Sommer explains. “But for the leafy greens, you want to go higher. About 2 cups of those make one serving.”

On top of their many health benefits, another reason to love cruciferous veggies is how easy they are to incorporate as a snack or meal. Try these ideas:

1. Much on raw broccoli and cauliflower on their own or dipped in a bit of hummus. Kick it up a notch with this homemade red pepper hummus.
2. Add some extra crunch to your salad by mixing in arugula, kale and some finely sliced radish.
3. Get your fill of cabbage with this southwestern twist on coleslaw.
4. Try these recipes for roasting, sautéing and dressing up brussels sprouts.
5. Cook your chicken or salmon on a thick bed of bok choy and cabbage.
6. Slice cauliflower into thick “steaks” and then coat with any combination of toasted sesame seed oil, lemon juice, soy sauce, cumin, coriander, anise or chili pepper.

The U.S. Department of Agriculture (USDA) also shares a selection of recipes and suggestions for preparing cruciferous vegetables on its website.

Cruciferous veggies have an important part to play in a healthy diet. But Sommer is quick to remind us that they’re just one part of the equation.

“A healthy diet should include a wide range of produce,” she advises. “We encourage people to ‘eat the rainbow.’ That is, enjoy a variety of colors and flavors in your fruits and vegetables. That way, you can be certain you’re getting an array of the vitamins and minerals that keep your body healthy.”