A few years ago a patient came into my office complaining of migraines. He said, “You might think I’m crazy, doc, but I get headaches when I eat certain vegetables.”
Which ones? He couldn’t be sure. Sometimes salads gave him a headache, usually in restaurants. Cole slaw gave him a headache no matter where he ate it. The list seemed completely random and included Brussels sprouts, watercress, broccoli and radishes.
I grinned like an amateur holding a royal flush. The patient was naming only cruciferous vegetables.
Cabbage family cousins
Many common vegetables belong to the cabbage family (genus Brassica). The edible members of this family are called cruciferous vegetables. That’s because their four-petaled flowers look like a crucifer, or cross.
Cruciferous veggies include:
- Arugula (or rocket)
- Bok choy
- Brussels sprouts
- Collard and mustard greens
- Daikon radish
- Rapini (broccoli rabi)
An ancient family tree
Ever hear about the triangle of U? A botanist named U theorized that all modern-day cruciferous vegetables evolved from three different ancestral plants in various configurations.
Over the ages, gardeners also influenced the great variety of cruciferous veggies we have today. They selectively bred plants for certain appealing characteristics. For example:
- Kale is grown for its leaves.
- Kohlrabi is grown for its (swollen) stems.
- Broccoli and cauliflower are grown for their buds.
Enjoying these veggies
Luckily, except for the patient whose unusual story I’ve shared, most of us get to enjoy cruciferous veggies without suffering any negative consequences whatsoever.
Cruciferous veggies taste great on their own. I can eat fresh arugula from my garden by the handful. The sweet, spicy crunch of a pure, translucent slice of radish or kohlrabi is like nothing else.
The strong flavors of cruciferous veggies stand up against lots of distinctive spices, herbs and garnishes. For example, try cooking chicken or salmon on a thick bed of bok choy and cabbage with a sauce of balsamic vinegar, olive oil, garlic, ginger, honey, fresh tomato, salt and pepper. Just toss everything into the blender, and give it a whirl.
Cauliflower can be steamed whole, and then coated with any combination of toasted sesame seed oil, lemon juice, soy sauce, cumin, coriander, anise or chili pepper. This dish makes a particularly impressive presentation, and it’s on almost everyone’s diet, whether gluten-free, vegan or paleo!
Many health benefits
The importance of this family of foods to our diet cannot be overstated. To begin with, cruciferous vegetables contain lots of:
- Soluble and insoluble fiber
- Vitamin C
- Vitamin B9 (folate)
They are also rich sources of compounds known as glucosinolates, which may help to fight cancer. (I am going to take a guess that these sulfur-containing compounds were the cause of my patient’s headaches.)
Certain enzymes in cruciferous veggies may help protect cell DNA from damage, and others may have antioxidant properties. Crucifers may also help to counteract cancer-causing nitrosamines and polycyclic aromatic hydrocarbons such as may be found in charred, cured or barbecued fish or meats.
Some researchers have suggested that sulforaphane may play a major role in preventing prostate and colon cancer. Sulforaphane are found in high levels in:
- Broccoli sprouts (sold next to the alfalfa sprouts)
- Bok choy
- Brussels sprouts
So increase your dietary intake of broccoli and other cruciferous vegetables. They can’t hurt, and they might help. And their strong, distinctive flavors will spice up any meal.