The Super-Veggies: Cruciferous Vegetables
Cruciferous vegetables have it all: vitamins, fiber, and disease-fighting phytochemicals. Here's how to get more of them.
What do broccoli, cauliflower, Brussels sprouts, kale, cabbage, and bok choy
have in common?
They're all members of the cruciferous, or cabbage, family of vegetables.
And they all contain phytochemicals, vitamins and minerals, and fiber that are
important to your health (although some have more than others.)
In fact, health agencies recommend that we eat several servings per week of
cruciferous vegetables -- and for good reason.
Lower Cancer Risk?
One of the big reasons to eat plenty of cruciferous vegetables is that they
may help to lower your risk of getting cancer.
A review of research published in the October 1996 issue of the Journal
of the American Dietetic Association showed that 70% or more of the studies
found a link between cruciferous vegetables and protection against cancer.
Various components in cruciferous vegetables have been linked to lower
cancer risks. Some have shown the ability to stop the growth of cancer cells
for tumors in the breast, uterine lining (endometrium), lung, colon, liver, and
cervix, according to the American Institute for Cancer Research. And studies
that track the diets of people over time have found that diets high in
cruciferous vegetables are linked to lower rates of prostate cancer.
Lab studies show that one of the phytochemicals found in cruciferous
vegetables - sulforaphane - can stimulate enzymes in the body that detoxify
carcinogens before they damage cells, says Matthew Wallig, DVM, PhD. Through
different mechanisms, two other compounds found in cruciferous vegetables --
indole 3-carbinol and crambene -- are also suspected of activating
Further, research suggests there is some important synergy between the
various compounds in cruciferous vegetables. Wallig, professor of comparative
pathology at the University of Illinois at Urbana-Champaign, discovered that
crambene is more active when combined with indole 3-carbinol.
Another way cruciferous vegetables may help to protect against cancer is by
reducing oxidative stress. Oxidative stress is the overload of harmful
molecules called oxygen-free radicals, which are generated by the body.
Reducing these free radicals may reduce the risk of colon, lung, prostate,
breast, and other cancers.
In a study funded by the National Cancer Institute, 20 participants were
encouraged to eat 1 to 2 cups of cruciferous vegetables a day. After three
weeks, the amount of oxidative stress in their body was measured. Then, after a
three-week wash-out period, the study participants were told to take a
multivitamin with fiber. Again, the oxidative stress was measured three weeks
And the results? Oxidative stress in the subjects' bodies dropped 22% during
the period when they were eating lots of cruciferous vegetables. But the change
during the multivitamin segment was negligible (0.2%), says lead researcher Jay
H. Fowke, PhD, an assistant professor and cancer epidemiologist for the
Department of Medicine at Vanderbilt Medical Center in Nashville, Tenn.
More study is needed, but Fowke feels the evidence is pretty strong that
eating cruciferous vegetables is a particularly healthful choice.
"There's no harm to it and consistently, across the line, it's
associated with improved health and a reduced risk of various chronic
diseases," he says in an email interview.
It's best, he says, to eat these veggies raw or only lightly steamed to
retain the phytochemicals that make cruciferous vegetables special in terms of