A Green Giant?
Souped-upbroccoli may be new cancer weapon
By Liz Lynch
THURSDAY, June 1 (HealthSCOUT) — Now you can ditch that boring old regularbroccoli in favor of a plate of superbroccoli. Mind you, the new stufftastes the same as the old stuff, so for those who dislike broccoli, this is notexciting news. But this newly bred broccoli could be a potent weapon in cancerprevention.
Scientists at the Institute for Food Research in Norwich, England,crossed a wild Sicilian strain of broccoli with an ordinary variety to producethe new broccoli. They describe it in the current issue of New Scientist.
It looks and tastes the same as your basic broccoli, but the new variety contains10 times as much sulforaphane as its ordinary cousin, says Gary Williamson,head of the superbroccoli research team. Sulforaphane is one of a number ofplant byproducts thought to help neutralize cancer-causing substances in thebody. Apparently, when released in the stomach, sulforaphane steps up productionof cancer-fighting enzymes.
Just how this happens, however, is still being untangled by researchers. In astudy set to begin later this year, Williamson plans to further examine theprocess by having people eat either regular broccoli or superbroccoli and thencomparing the effects. He expects that to indicate whether the superbroccoliboosts concentrations of anti-cancer enzymes in the blood even higher thanregular broccoli does.
Sulforaphane is derived from a substance called glucoraphanin, a “secondarymetabolite” of the plant. “Plants don’t have kidneys, so they producecomplex secondary metabolites instead,” explains Elizabeth Jeffery, anutrition professor at the University of Illinois. “[The secondarymetabolites] play hormone-like roles in the plant or protect the plant fromnoxious insects and other predators.”
In cruciferous vegetables such as broccoli, several substances, includingsulforaphane, are produced from secondary metabolites. Several of these products”have been found to be active in cancer prevention trials,” Jefferysays. Cruciferous vegetables — a family of vegetables known for the shape oftheir flowers and pods and for their strong odor — also include cabbage,turnips, radish and horseradish.
While glucoraphanin and its derivative, sulforaphane, can be found in a numberof vegetables, “it is in much higher concentration in broccoli than othervegetable types,” she says. Still, the amount of sulforaphane varies widelyamong types of broccoli.
“Notall broccolis are created equal,” Jeffery says, “and the new productfrom Britain is even more unequal.” But does any of this add up to adviceon how much broccoli to eat?
Fewstudies have pinpointed things that precisely, Jeffery says. In clinical tests,people who ate 250 grams a day of cruciferous vegetables raised their levels ofanti-cancer enzymes, she says. And, she adds, “as little as two to threeservings a week was found to significantly decrease risk for prostrate cancer ina study in the Journal of the National Cancer Institute earlier thisyear.