New research suggests that steaming vegetables such as broccoli may power their natural cancer-fighting properties.
HealthDay News reports that cruciferous vegetables such as broccoli contain sulforaphane, a phytochemical and naturally occuring plant compound that has been shown to contain strong anti-cancer properties. In order for sulforaphane to form, the enzyme myrosinase is necessary, and some means of preparing veggies may destroy it.
Researchers found that of three methods to prepare veggies, including boiling, steaming and microwaving them, steaming broccoli was the best way to retain its myrosinase and preserve cancer-fighting sulforaphane, while boiling and microwaving them for one minute or less destroyed most of the myrosinase enzyme.
Elizabeth Jeffery, a researcher at University of Illinois at Urbana-Champaign, told HealthDay News that in addition to well-cooked broccoli, "mustard, radish, arugula, wasabi and other uncooked cruciferous vegetables such as coleslaw all contain myrosinase," which when steamed can help restore the enyme myrosinase.
The researchers recommend steaming the vegetables until they turn a bright green color.
"Past food processing has tended to focus on improving taste, visuals and microbiological safety," Jeffrey told HealthDay News. "Now our task is to go further. Processing can ensure that the bioactives - the cancer protective compounds - arrive in your digestive system in a form the body can use."
These preliminary findings were presented on Nov. 7 at the annual meeting of the American Institute for Cancer Research in Bethesda, Md. and have not yet been published in a peer-reviewed journal.
