KING OF THE CRUCIFERS
Protect against heart disease
Fight off cancer
Boost immunity
If fruits and vegetables had an annual yearbook, broccoli might not win the Tastiest of the Year honor. But it would definitely be in the running for Most Likely to Prevent Cancer.
Scientists around the world are using high-tech methods to learn which compounds contained within this vegetable might be helpful in confronting cancer. And they’re finding plenty of them.
Broccoli’s impressive power as a cancer fighter is due in part to its multipronged attack. It contains at least two separate compounds—indole-3-carbinol (or I3C, for short) and sulforaphane—that help sweep up cancer-causing substances before they have a chance to do harm.
The compound I3C, which is also found in cabbage and Brussels sprouts, seems to be able to prevent or interrupt cancer in several ways.
The hormone estrogen causes cells in the breasts to multiply and grow. This is a natural and normal process in women. However, if mutated cells that could become cancerous develop in the breasts, estrogen causes these to multiply, too. That’s bad. To cause breast cells to perform certain activities, estrogen must first attach to “receptors” on the cells, kind of like a key fitting into a lock. The I3C compound appears to act on these receptors, perhaps by keeping estrogen from attaching to them, or changing the way they work. Thus, estrogen can’t have its tumor-encouraging role on the cells.
In addition, I3C may help shift the balance of different types of estrogen in the body so that you have less of a type that does promote breast cancer growth, and more of a type that doesn’t. I3C may also trigger cancerous cells to die, a process called apoptosis, and may raise your levels of enzymes that protect you from cancer-causing substances.
Beyond its potential effects on breast cancer, I3C has been shown to inhibit the growth of prostate and cervical cancer cells. In addition, numerous studies have shown that a diet high in cruciferous vegetables, such as broccoli, may reduce the risk of colon cancer.
Researchers investigating I3C’s potential effect on cervical cancer gave supplements of the substance for 12 weeks to 30 women who had precancerous changes on their cervix. In roughly half of the women who took supplemental I3C, these worrisome lesions regressed. This didn’t happen in any of the women who took a placebo (dummy pill).
While I3C is conducting its anticancer activities, another component called sulforaphane is offering protection on another front, by boosting the production of cancer-blocking enzymes, says Thomas Kensler, PhD, professor in the department of environmental health sciences in the Bloomberg School of Public Health at Johns Hopkins University in Baltimore.
In one pioneering study, Dr. Kensler and his colleagues at Johns Hopkins exposed 145 laboratory animals to a powerful cancer-causing agent. Twenty-five of the animals had not received any special treatment, while the rest were fed high doses of sulforaphane. After 50 days, 68 percent of the unprotected animals had breast tumors, compared with only 26 percent of those given the sulforaphane.
Other lab studies have found that sulforaphane may help protect against cancer of the prostate, colon, and pancreas. More recent research has also found clues that sulforaphane may have other cancer-fighting properties in addition to boosting your anticancer enzymes. It may help inhibit germs that contribute to cancer, such as the H. pylori bacteria that raise the risk of stomach cancer. It may also interfere with cancer cells’ growth cycle and may help encourage the cells to die.
It is no wonder that researchers put broccoli at the top of their lists of nutritional superstars. “We know that those people who eat lots of cruciferous vegetables, including broccoli, are protected from many forms of cancer,” says Jon Michnovicz, MD, PhD, president of the Foundation for Preventive Oncology in New York City.
One of the problems with cooking broccoli is consistency—or, more specifically, a lack thereof. Broccoli consists of both tough stalks and tender florets, the result being that it often ends up with some parts either overdone or underdone.
To help ensure even cooking, it’s helpful to cut broccoli into little spears. First, cut off and discard the thick, woody part of the stalk, generally from the bottom up to where the broccoli florets begin to branch. Then cut any large florets and stems in half lengthwise.
If you find that the stems are still too tough for eating, either trim them farther up from the bottom or peel them with a vegetable peeler before cooking.
While much recent research has focused on “exotic” compounds like sulforaphane, broccoli is also chock-full of more commonly known, but still powerful, compounds like beta-carotene. This nutrient, which the body converts to vitamin A, is an antioxidant. That is, it helps prevent disease by sweeping up harmful, cell-damaging oxygen molecules that naturally accumulate in the body. High levels of beta-carotene have been linked to lower rates of heart attack, certain cancers, and cataracts.
Broccoli is an excellent source of beta-carotene, providing about 0.7 milligram in a half-cup cooked serving. This provides 7 to 12 percent of the recommended daily amount.
While gently cooking broccoli helps release some of its protective compounds, overheating it can destroy others. “Carotenoids like beta-carotene are preserved by heat, but the indoles, like I3C, don’t withstand a lot of heat,” explains Jon Michnovicz, MD, PhD, president of the Foundation for Preventive Oncology in New York City. “Light steaming is a great way to cook broccoli. And microwaving is okay, too.”
Broccoli isn’t called the king of the crucifers for nothing. Besides beta-carotene, sulforaphane, and I3C, broccoli contains a variety of other nutrients, each of which can help fend off a host of conditions, from heart disease to osteoporosis.
For example, just a half-cup of chopped, cooked broccoli contains 85 percent of the Daily Value (DV) for vitamin C. This antioxidant vitamin has been proven in studies to help boost immunity and fight diseases like heart disease and cancer.
Broccoli also ranks highly for women’s health, particularly for women who don’t get enough dairy food. It’s one of the best vegetable sources of calcium, packing in 72 milligrams per cooked cup—about a quarter of the amount in an 8-ounce glass of fat-free milk. Calcium is well-documented as the single most important nutrient that women need to keep osteoporosis (the breaking down of bones) at bay.
Broccoli is also rich in folate, a nutrient that’s essential for normal tissue growth and that studies show may protect against cancer, heart disease, and birth defects. Women, especially those who take birth control pills, are often low in this vital nutrient. A cup of chopped, cooked broccoli contains 84 micrograms, or almost one-quarter of the DV for folate.
Finally, if you’re looking to keep your digestive system running smoothly, make broccoli your food of choice, experts advise. A half-cup provides 2 grams of fiber, which is a proven protector against constipation, hemorrhoids, colon cancer, diabetes, high cholesterol, heart disease, and obesity.
Experts aren’t yet sure how much broccoli you need to maximize its healing potential. Dr. Kensler advises eating at least five servings of fruits and vegetables a day, while reaching for this crunchy crucifer whenever you can.
Buy it purple. You’ll notice at the supermarket that broccoli is sometimes so dark that it’s almost purple. That’s good. The dark color means that it has more beta-carotene, experts say. If it’s yellowish, on the other hand, skip it. That means that it’s old, and its nutritional clock is running down.
Look for the sprouts. Studies at Johns Hopkins University in Baltimore found that 3-day-old broccoli sprouts can contain up to 100 times the amount of protective substances in the mature vegetable. These can provide a great alternative if you don’t care for the taste of mature broccoli (and you may get the same cancer-fighting benefit by eating a smaller amount of sprouts than regular broccoli). Broccoli sprouts look like white strings with little green heads. They’re perfect for salads or sandwiches, but they quickly spoil in the refrigerator, so only buy an amount that you can eat in a few days. You’ll likely find them in plastic containers in the produce section of your supermarket.
Preheat the oven to 375°F.
Place the broccoli and the garlic in a microwaveable bowl. Cover and microwave on high for 45 seconds. Transfer to a food processor, and add the basil, oil, lemon juice, water, Parmesan, walnuts, and salt. Process 1 minute, or until smooth.
Cut around the edge of the pitas, and split in half. Place the pita halves on a baking sheet, rough side down, and bake for 8 minutes. Turn over, and spread each half with 1½ tablespoons of the pesto. Top evenly with some roasted pepper and mozzarella. Bake for 8 minutes longer, or until heated through.
Cook’s Notes: The broccoli pesto can be made ahead and refrigerated in an airtight container for up to a week. It can also be drizzled on pasta and veggies, added to soup, or used as a spread.
Makes 4 servings (2 pizzas each)
Calories: 230
Total fat: 12 g
Saturated fat: 4 g
Cholesterol: 10 mg
Sodium: 540 mg
Dietary fiber: 3 g