Research Summary and Preliminary Evidence

Wasabi japonica, commonly known as wasabi, is a popular condiment traditionally served in Japanese cuisine. References in Japanese literature to the consumption of wasabi date back to at least the tenth century AD. Here in the US, wasabi is associated with healthy diets, Asian cooking, and Japanese sushi.

Over the centuries, the Japanese have believed that eating grated fresh wasabi with raw fish and other foods helped prevent illness. Scientific evidence today confirms they are correct; Scientists have discovered the isothiocyanates in wasabi are antimicrobial. Wasabi not only kills many bacteria’s associated with fish but also kills some forms of E-coli an Staphylococcus.

The pungent taste of wasabi and other cruciferous plants is derived from the breakdown of glucosinolates. Glucosinolates are large sulfur rich phytomolecules stored in the cells of plants. In nature, they are released from plant cells when plants are damages. This defensive response is primarily triggered by the actions of feeding animals and insects but it also caused by grating. These glucosinolates are released and converted to isothiocyanates by the enzyme myrosianse which is physically separated within plant cells. This reaction is what gives wasabi, upon grating, its characteristic flavor and hotness.

Recently, the glucosinolates and isothiocyanates contained in wasabi and other cruciferous plants such as broccoli, cauliflower, kale, turnips, cabbage and brussel sprouts have been drawing attention as scientists research their potential chemprotection against cancer. Scientific research institutions conducting studies about the anti-cancer properties of wasabi in Japan include the Division of Applied Food Research, National Institute of Health and Nutrition; Cancer Research Institute, Kanazawa University; Nagoya University Graduate School of Bioagricultural Sciences; Department of Food Science and Human Nutrition, Tokyo Metropolitan College, and The Skylark Food Science Institute. Glucosinolates in cruciferous plants are also being extensively studied here in the USA at John Hopkins University, School of Medicine.

The colors of different grated wasabi species

The colors of different grated wasabi species

Reducing Risk of Some Cancers with Diet

With over 100 million new cancer cases diagnosed each year worldwide, medical investigators are taking a closer look at how diet may help reduce cancer risk. Experts believe that 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 cancer. Researchers are now investigating specific photochemical found in fruits and vegetables that may serve as weapons against cancer and other diseases. (1) During the last decade, researchers studying plant glucosinolates have made a series of breakthrough discoveries. Their scientific findings may help explain the widely recognized scientific evidence indicating that populations consuming a diet rich in fruits and vegetables, and especially cruciferous vegetables, have a reduced risk of developing several types on cancers. (2-9) The US National Cancer Institute states &;Chemoprevention is the use of natural and synthetic substances to reduce the risk of cancer. NCI’s chemoprevention research effort has grown considerably since it was established in the early 1980’s.” (10) According to Paul Talalay, MD, Professor of Pharmacology at Johns Hopkins University, School of Medicine, “Chemoprotection is a deliberate effort to increase the body’s defense systems against chemicals, including carcinogens, that can lead to disease. Chemoprotection may lower a person’s risk of developing cancer by building up the body’s own defenses, particularly though diet.” (11)

This 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.

Glucosinolates In Wasabi

Wasabi is a rich source of phytochemicals which include glucosinolates. Scientist have previously isolated and identified the glucosinolates and its breakdown sulforaphane compounds in some cruciferous vegetables as one of the most potent boosters of Phase 2 enzymes, which stimulate the ability of animal cells to protect against disease. (12)

Recently scientists in Japan have discovered that the special glucosinolates in wasabi are up to 1.9 times more powerful than the glucosinolates contained in broccoli. (13) Wasabi also contains additional unique and important glucosinolates not found in other plants.

Antioxidant Activity Created by Glucosinolates

Glucosinolates stimulate antioxidant protection by the body itself. They pass intact though the stomach and into the small intestines. There, the micro flora breaks down the glucosinolates into isothiocyanates and then to sulforaphanes. The sulforaphanes trigger the liver to increase production of Phase 2 enzymes. These enzymes help detoxify the body of potential chemical carcinogens by destruction of their reactive centers or by neutralizing their toxic properties and accelerating their elimination from the body. (14) This antioxidant effect of sulforaphanes has been shown to last for days, not hours, as is the case with vitamins C and E. (15) Everyday, efforts are being made to better understand the effects of diet on cancer. Using plant photochemical to increase Phase 2 enzymes in humans is a promising part of the rational development of a diet rich in fruits and vegetables to help reduce the risk of cancer.

Anti-platelet Isothiocyanates in Wasabi

It is well know that some chemicals play an important role in helping to prevent heart attacks because of their blood anti-platelet aggregation properties. Preliminary scientific studies show that the isothiocyanates contained in wasabi have strong anti-platelet properties. Wasabi isothiocyanates have been shown to work ten times faster than aspirin. Wasabi may be a valuable use in hospitals for treating heart attack victims in the emergency room. (16)

+ These statements have not been evaluated by the Food and Drug Administration. Cruciferous vegetables, including wasabi and broccoli, are not intended to diagnose, treat, cure, or prevent any disease.

Wasabi crop growin in Japan