The role of these special enzymes appears to be scavenging for cancer-causing molecules. Now a new study adds to these positive reports about sulforaphane by proposing that the compound may additionally play a more direct role in cancer prevention by inducing cell cycle arrest and apoptosis [Cancer Res 2000 Mar 1;60(5):1426-1433]. After treating human colon cancer cells with sulforaphane, the researchers found a number of chemical and structural cellular changes that indicated cancer cells were being killed off by the compound. The study authors also go on to explain that broccoli contains a stable sulforaphane precursor (isothiocyanate), which causes broccoli to release its sulforaphane content when the vegetable is chewed or chopped.
Earlier research at Johns Hopkins University found that sulforaphane blocked the formation of mammary tumors in rodents treated with a potent carcinogen [Proc Natl Acad Sci USA 1994;91:3147-3150]. Results showed that the number of rats that developed tumors was reduced by 60%, the number of tumors they developed dropped by 80%, and tumor size decreased by 75%. Other research by the American Health Foundation showed that sulforaphane inhibited the appearance of premalignant lesions of colon cancer in rats [Proc Natl Acad Sci USA 2000;41:660]. And, almost a decade ago, scientists had found that sulforaphane boosted the activity of two detoxifying enzymes-quinone reductase and glutathione transferase-in experimental mice [Proc Natl Acad Sci USA 1992 Mar 15;89(6):2399-2403]. As a result, scientists speculated that sulforaphane may regulate the metabolism of carcinogens, possibly by helping to neutralize harmful molecules and minimizing the oxidative damage that predisposes cells to cancerous growth. Now the latest research adds another piece to the puzzle that explains how sulforaphane goes about subduing cancerous growth and development.
Broccoli contains sulforaphane, a substance that has anti-bacterial and anti-cancer properties. Sulforaphane is found in cruciferous vegetables such as brussel sprouts, cauliflower, bok choy, kale, broccoli, cabbage, collards, kohlrabi, mustard, turnip, radish, and watercress. It is a potent inducer of protective enzymes that provide defense against cancer-causing chemicals. Eating more broccoli and other cruciferous vegetables is associated with a lower risk of bladder cancer. Broccoli contain 20 to 50 times the concentration of sulforaphane that mature broccoli does. Cooking reduces the levels of sulforaphane in broccoli. Human Study Finds Broccoli Boosts Body’s Ability to Eliminate Cancer-Causing Toxins – Researchers from Johns Hopkins University School of Medicine and Bloomberg School of Public Health have observed that broccoli can help the body detoxify carcinogens, which may reduce the risk of developing liver cancer. The study used three-day-old broccoli with known levels of sulforaphane glucosinolate and involved 200 subjects. November, 2005 issue of Cancer Epidemiology Biomarkers & Prevention.Compounds in broccoli and other cruciferous vegetables called isothiocyanates appear to target and block mutant p53 genes associated with cancer growth. Gene p53 is known as a tumor suppressor gene and plays a critical role in keeping cells healthy and protecting them from cancer. When this gene is damaged or mutated, it stops offering this protection. These mutations are found in about half of all human cancers. Isothiocyanates are capable of removing the defective p53 gene while leaving healthy versions of the gene alone.
Researchers in Japan looked at how regularly dining on broccoli sprouts affected a common stomach bacterium called Helicobacter pylori. H pylori infection doesn’t always cause symptoms, but it can lead to stomach inflammation (gastritis) and ulcers. It’s also considered a major risk factor for stomach cancer. Studies in animals have shown that sulforaphane from broccoli sprouts can rein in this bacterium, and also reduce inflammation and cell damage that could lead to cancer. But not much research has been done in people.
In the new study, researchers enlisted 48 men and women who had H pylori but had not been treated for it. Over eight weeks, some ate 2.5 ounces of alfalfa sprouts daily, and others ate 2.5 ounces of broccoli sprouts, which contain as much sulforaphane as two to three servings of broccoli.
Researchers monitored the participants’ H pylori levels using breath, blood, and stool tests. Among those eating broccoli sprouts, H pylori levels were significantly lower at the end of the study than at the start. Levels were unchanged for those eating alfalfa sprouts. The researchers also looked at markers of inflammation in the participants’ blood called pepsinogen I and II. These declined during the study for those eating broccoli sprouts, but remained the same for those eating alfalfa sprouts. However, once people stopped eating broccoli sprouts, their levels of H pylori and pepsinogen I and II eventually went back to where they were at the beginning of the study.
Nutrition Facts
Organic Broccoli powder
Nutrition Facts 100 grams
Amount Per Serving
Calories 256
Total Fat 0g
Saturated Fat 0g
Trans Fat 0g
Cholesterol 0mg
Sodium 105mg
Potassium 0mg
Total Carbohydrate 58g
Dietary Fiber 12g
Sugars 23g Added 0 sugar
Protein 23g
Vitamin A 19755 IU
Vitamin D 0 mcg
Calcium 103 mg
Iron 16 mg
Vitamin C 220 mg
*Percent Daily Values are based on a 2000 calorie diet. Your daily values may be higher or lower depending on your calorie needs.
Ingredients: Organic Broccoli powder
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*These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure or prevent any disease.
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