You’ve probably already heard about the health benefits of broccoli, partially due to the sulforaphane content of the plant. A new study from Johns Hopkins discovered that the level of sulforaphane in broccoli sprouts is 20 to 50 times higher than the full sized plant.
Sulforaphane helps rev up the body’s natural cancer-fighting system, and cuts the risk of developing cancer. Paul Talalay, M.D. and professor of pharmacology J.J. Abe found that 3-day-old broccoli sprouts consistently contain 20-50 times the amount of chemo-protective compounds found in mature broccoli heads, and may offer an effective dietary means of reducing cancer risk in different-age people.
Talalay’s research team reached the results by giving extracts of broccoli sprouts to groups of 20 female rats for five days, and exposed them to the carcinogen dimethylbenzanthracene and, at the same time, coupled a parallel control group that did not receive the extracts, but was only exposed to the same carcinogen.
The rats that received the extracts developed fewer tumors. Even those that did develop tumors had smaller growths that took longer to grow. In a paper, published in the proceedings of the National Academy of Sciences, Talalay and his associates describe their successful efforts to build on their 1992 discovery of sulforaphane’s chemo-protective properties. The entire work described in the study is a subject of issued and pending patents.
Ardent previous systematic search of dietary sources of compounds able to stimulate resistance to cancer-causing agents made Hopkins’ group focus on naturally-occurring compounds in edible plants that mobilize Phase 2 detoxification enzymes.
These enzymes are able to neutralize highly reactive, dangerous formulas of cancer-causing substances before they can ‘succeed’ to damage DNA and thus give a “green light” to cancerous developments. It was found that exactly sulforaphane is a very potent promoter of Phase 2 enzymes, as reported by Jed Fahey, plant physiologist and manager of the Brassica Chemoprotection Laboratory at Hopkins. The broccoli contains unusually high levels of glucoraphanin, the naturally-occurring precursor of the targeted sulforaphane.
Further tests, done in a new study, showed that glucoraphanin’s levels in broccoli samples were highly variable, so there was no certain way to tell which broccoli plants had the highest amount of the desired compound without conducting an elaborated chemical analysis. Moreover, Talalay said that even if that was possible, people would still have to consume unreasonably large quantities of broccoli to get any significant promotion of Phase 2 enzymes.
More clinical studies have also been reported to see if eating a few tablespoons of the broccoli sprouts every day can provide an equal degree of chemo-protection as does ½ to 1 kilogram (1-2 pounds) of broccoli eaten weekly. Mr. Talalay says that the broccoli sprouts look and taste similarly to alfalfa sprouts.
Talalay founded the Brassica Chemoprotection Laboratory, a Hopkins center that focuses on identifying chemo-protective nutrients and finding ways to augment their anti-cancer effects. The lab was named after the plant genus Brassica, more commonly known as the Mustard family. In addition to broccoli, it also includes: kale, Brussels sprouts, cabbage, cauliflower and turnips.
Mr. Talalay says that man-made compounds that increase the resistance of cells and tissues to carcinogens were currently being developed, but could require years of clinical trials to determine safety and efficacy for future generations. But there’s still good news.
“For now, we may get faster and better impact by looking at dietary means of supplying that protection. Eating more fruits and vegetables has long been associated with reduced cancer risk, so it made all sense for us to look at vegetables. Cancer-research scientists currently ought to continue to develop new ways of detecting and treating cancer once it is established, but it also makes sense to pay more attention on efforts to prevent cancer from occurring or re-occurring.”
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