Explore this section to learn more about the science behind SGS, cancer protection and BroccoSprouts.

History of Discoveries

It has been widely accepted for decades that a diet rich in fruits and vegetables is important for good health. It is safe to say that everyone has a memory of being told to, "Eat your vegetables. They are good for you!" But why is a diet rich in fruits and vegetables good for us? Extensive epidemiological evidence, backed by animal experiments, has established in the scientific community with very little doubt that a diet rich in fruits and vegetables is associated with large and dose-related reduction in the risk of developing cancer. Yet these observations do not answer the fundamental question of how such a diet can protect against cancer. This is the question to which Dr. Paul Talalay has dedicated his life's work. Dr. Talalay is the John Jacob Abel Distinguished Service Professor of Pharmacology and Director of the Laboratory for Molecular Sciences at Johns Hopkins University School of Medicine in Baltimore. He is also the founder of The Brassica Chemoprotection Laboratory, which is dedicated to studying edible plants that induce protective enzyme activity in the body and may help to prevent cancer development.

Dr. Talalay has devoted his career to cancer research, focusing his efforts on achieving early protection against cell damage. A pioneer in the field of chemoprotective research strategies, Dr. Talalay and his colleagues devised simple cell culture methods for detecting phytochemicals which appear to boost enzymes that detoxify carcinogens in the body.

Reducing Risk of Some Cancers with Diet

With 10.3 million new cancer cases diagnosed each year worldwide, medical investigators are taking a closer look at how diet may help reduce cancer risk. As many as two-thirds of these cancers may be caused by diet and lifestyle factors. A number of studies indicate that diets rich in fruits and vegetables contribute to decreased risk of many types of cancers. Researchers at Brassica Protection Products are now investigating specific phytochemicals found in fruits and vegetables, that may serve as weapons against cancer and other diseases.

During the past eight years, in the culmination of decades of scientific research, Dr. Talalay and his team of researchers at Johns Hopkins University School of Medicine made a series of breakthrough discoveries in this area. Their scientific findings relating to SGS™ (sulforaphane glucosinolate), a compound found in broccoli, may help to explain the widely recognized scientific evidence indicating that populations consuming a diet rich in fruits and vegetables, and especially cruciferous vegetables such as broccoli, have a reduced risk of developing several types of cancers. Now, other institutions around the world have also begun to conduct research on the role of SGS in cancer prevention and protection. These independent studies have confirmed the work done by Dr. Talalay and have expanded our understanding of SGS.

Chemoprotection

Dr. Talalay's initial research targeted the potential chemoprotective effects of certain vegetable varieties. "Chemoprotection is a deliberate effort to increase the body's defense systems against chemicals, including carcinogens, that can lead to disease," according to Dr. Talalay. "Chemoprotection may lower a person's risk of developing cancer by building up the body's own defenses, particularly through diet." Dr. Talalay's strategy of chemoprotection takes advantage of the body's Phase 2 detoxification enzymes that help neutralize cancer-causing chemicals, as well as free radicals, before they can damage DNA and initiate the development of cancer.

The Sulforaphane Discovery

As part of this research strategy, in 1992, Dr. Talalay and his colleagues at Johns Hopkins University isolated and identified sulforaphane, a natural compound found in broccoli. They found sulforaphane to be the most potent booster of Phase 2 enzymes, which stimulate the ability of animal cells to protect against disease.

Antioxidant Activity of Sulforaphane

Sulforaphane exists in cruciferous vegetables such as broccoli and cabbage. In its precursor form, sulforaphane glucosinolate (SGS) functions as an indirect antioxidant. As such, this compound does not directly neutralize free radicals as do direct antioxidants like vitamins E and C and beta-carotene. Indirect antioxidants induce (or boost) the activity of the Phase 2 detoxification enzymes. According to Dr. Talalay, "These enzymes act as a defense mechanism, triggering broad spectrum antioxidant activity that neutralizes many free radicals, cycling over and over again before they can cause the cell damage that may cause mutations, leading to cancer." Furthermore, Dr. Talalay says that the effects of these indirect antioxidants remain even after they have left the body - unlike direct antioxidants, which neutralize only one molecule of a radical at a time, and are destroyed in the process. The indirect antioxidant effects are long-lasting, triggering an ongoing process that continues to be effective and may last for days.

SGS Blocks Tumors in Animals

In 1994, Dr. Talalay and his group of researchers tested the efficacy of sulforaphane in animals. Their research found that sulforaphane blocked the formation of mammary tumors in rats treated with a potent carcinogen: The number of rats that developed tumors was reduced by as much as 60%, the number of tumors in each animal was reduced by 80%, and the size of the tumors that did develop was reduced by 75%. Furthermore, the tumors' appearance was delayed and they grew more slowly. Most recently, researchers from the U.S. and Europe have further examined the effects of SGS in cancer models. Scientists at the American Health Foundation discovered that sulforaphane inhibited the formation of premalignant lesions in the colons of rats. Furthermore, researchers in Toulouse, France found that sulforaphane induced cell death in human colon carcinoma cells. This study suggests that "in addition to the activation of detoxifying enzymes, induction of apoptosis [cell death] is also involved in the sulforaphane-associated chemoprevention of cancer." These results have not yet been validated in humans.

High Levels of SGS Found in Broccoli Sprouts

Dr. Talalay and his team next examined a wide range of broccoli plants to determine which had the highest levels of SGS. First, Dr. Talalay and his researchers found that many varieties of fresh and frozen broccoli differed significantly in the amounts of SGS they contained and, thus, in their ability to increase protective Phase 2 enzymes. It was then discovered that as the plant grows older, the concentration of SGS decreased. Conversely, young plants (three-day-old sprouts) yielded much more concentrated enzyme-induced activity. Findings from this research demonstrated that certain varieties of three-day-old broccoli sprouts contained between 20 and 50 times the concentration of SGS as the mature, cooked vegetable.

Commercial broccoli is highly variable in SGS content.

The researchers discovered that young broccoli sprouts, grown from the seeds of certain varieties of broccoli, can be produced under carefully standardized conditions to contain consistently high concentrations of SGS. Researchers found that, on average, one ounce of these special sprouts provided as much SGS as 1 1/4 pounds (20 ounces) of mature, cooked broccoli (20 times the concentration).

The Johns Hopkins University School of Medicine has received six patents for this SGS-enhanced broccoli sprout discovery, and the University licensed these patents so that broccoli sprouts could be carefully monitored to ensure they contain optimal levels of SGS. These sprouts are now available to the public as BroccoSprouts®.

Brassica Chemoprotection Laboratory

To facilitate further study based on the promising results of the animal research - and with support from philanthropists, including Cullman Ventures, Inc., and the National Cancer Institute - Talalay founded the Brassica Chemoprotection Laboratory within Johns Hopkins University.

The Brassica Chemoprotection Laboratory is the first laboratory of its kind designed exclusively for the study of the chemoprotective properties of plants. Studies undertaken by Dr. Jed W. Fahey in the lab include:

1. Testing a wide variety of edible plants for their ability to raise chemoprotective (Phase 2) enzymes.
2. cultivating those plants that exhibit the highest levels of this activity and determining conditions that will further increase activity.
3. selecting, hybridizing and scientifically breeding plants to enhance their chemoprotective potency.

Conclusion

The Johns Hopkins strategy and discoveries are consistent with what many epidemiologic studies have shown: Many cancers may be related to lifestyle or extrinsic factors and are, therefore, in principle, preventable. Johns Hopkins researchers continue to focus on SGS and other compounds from edible plants that may have potential chemoprotective effects. More research needs to be undertaken to confirm the benefits of SGS in humans, but, according to Dr. Talalay, the outlook is very promising. A percentage of BroccoSprouts broccoli sprouts sales are contributed to The Brassica Foundation for Chemoprotection Research, which supports further research into the link between nutrition and cancer.