Another boost for broccoli Health: JHU research finds cancer-fighting starts young in cruciferous powerhouse.

Have you taken your broccoli today?

That notion, of consuming a "dose" of healthful food, got one step closer yesterday with a report from Johns Hopkins researchers that they've been able to identify a particular food source that packs a powerful wallop in terms of fighting cancer.


The food is broccoli, and the dose is a few ounces a week of its sprouts -- a hitherto unused form of the plant that contains a large amount of the chemical sulforaphane, a potent compound that aids cancer-fighting enzymes in the body.

The chemical was isolated in 1994 by molecular pharmacologist Dr. Paul Talalay and his team at Hopkins, two years after they had discovered evidence of cancer-fighting properties in plants of the brassica family -- broccoli, cauliflower, brussels sprouts, also called cruciferous vegetables.


Now Talalay and his researchers have identified the first "nutraceutical" -- that is, an ordinary food that if consumed in sufficient amounts, provides a dose of disease-preventing chemicals.

Scientists have known for some time that various foods contain chemicals that help the body ward off cell damage that could lead to cancer. These compounds are called "phytochemicals." They include isothiocyanates, found in cabbage and turnips, polyphenols, found in wine and green tea, and genistein, found in soy products and some green plants. And sulforaphane.

But up till now, no one has been able to say what a useful "dose" of any of these compounds might be.

Now Talalay and his cohorts, Jed Fahey and Yuesheng Zhang, have discovered that immature broccoli, still in the sprout stage, contains 20 to 50 times as much sulforaphane as mature plants (about 60 days old). The finding was "interesting and quite unexpected," Talalay said. And it solved the problem: Small amounts of sprouts every week -- a couple of ounces -- would easily provide the appropriate dose.

Broccoli sprouts look like tiny clover and have a clean, slightly astringent taste. Talalay calls consuming them "a new approach to fighting cancer," or "chemoprotection" -- efforts to increase the body's inherent defense mechanisms by consuming appropriate amounts of helpful substances.

"When the diagnosis of cancer is first made," Talalay said yesterday at a press conference announcing the report, to be published today in the Proceedings of the National Academy of Sciences, "usually it's at the stage of an early lesion. But the process has been developing for 10 to 25 years, and almost no attention has been given to battling cancer during that period." Instead, the emphasis is on destroying the tumor, with surgery, chemotherapy, radiation therapy, or some combination.

But using nutraceuticals like broccoli sprouts to prevent cell damage in the first place is "far more effective than fighting tumors" after they've formed, Talalay said.

The catch, of course, is that you can't walk into a grocery store and buy broccoli sprouts.


So Talalay hopes to remedy that with the formation of the private, nonprofit Brassica Foundation, which will develop ways to grow broccoli sprouts with an unvariable and adequate amount of sulforaphane in commercial quantities.

"We're hoping very much that by 1998, broccoli sprouts that satisfy our stringent requirements" will be available to consumers, he said.

Meanwhile, what should people do to get adequate amounts of sulforaphane and other phytochemicals?

Follow the recommendations of other health organizations, he said, and eat a large variety of fruits and vegetables. "We would concur even when broccoli sprouts become available," he said. "They would be in addition to, not instead of" a varied diet.

Pub Date: 9/16/97