TASTE THE ANTIOXIDANTS

Strong flavor and aroma signal potent anti-aging benefits

By Marcia Zimmerman, M.Ed., C.N.

As different in flavor as asparagus, broccoli and garlic are, these pungent foods share a remarkable antioxidant and disease preventing substance, It's sulfur! While some people are turned off by the strong odor and taste of sulfur compounds, it's important to pay attention to how these phytochemicals work, especially if you're interested in enjoying a long, vigorous life.

Cruciferous Vegetables

Investigations at Johns Hopkins School of Medicine have led to the conclusion that the cabbage family is the most important food group for preventing cancer. These cruciferous vegetables (a family that includes broccoli and its sprouts, cauliflower, kale, Brussels sprouts, mustard, daikon and other radishes, turnip and watercress) activate the body's own antioxidant enzymes. These enzymes transform both ingested toxins and harmful chemicals produced within the body during metabolism into compounds that can easily be excreted. Cruciferous vegetables affect two potentially harmful groups of compounds.

1. Environmental toxins Everything that you eat, drink and breathe must be processed by the liver. These include foods, beverages, medications and airborne chemicals. All of these substances are "foreign" to the body, so the liver must process them to extract what is good for us and prepare the harmful substances for elimination. Some of these toxins and their metabolic byproducts are free radicals that would otherwise wreak havoc on our cells.

The liver processes toxins through a two step enzyme system, known as phase I and phase II detoxification. The phase I enzymes make potentially harmful compounds more water soluble and, hence, more easily excreted. In turn, phase II enzymes dampen the toxic possibilities of the action of phase I enzymes on harmful substances. The phytochemicals in cruciferous vegetables, known as glucosinolates, activate both sets of detoxifying enzymes. By doing so, these sulfur compounds decrease tumor growth and the occurrence of cancer.

2. Hormones Excess levels of estrogen and testosterone, hormones that are needed for growth and reproduction also, can promote cancer. Enzymes in the liver link the active forms of the hormones with other compounds in the process known as conjugation. Conjugated hormones are water soluble and disposable forms that protect the body from more lethal active hormones.

Despite the efficiency of the detoxification enzymes, conjugated estrogens can be deconugated by another liver enzyme, beta glucuronidase. The reactivated estrogens become to bind with receptors in breast tissue and promote cellular events that lead to cancer. Glucosinolates in cruciferous vegetable prevent beta glucuronidase from reactivating conjugated estrogen, thus helping to prevent cancer.

Glucosinolates also convert into several biotransformation products, each having specific activities. Isothiocyanates, one group of these biotransformation products, have been linked with reduced incidence of lung and esophagaeal cancer among smokers.

Scientists have found that isothiocyanates act by switching off cancer promotion, while accelerating the binding and excretion of cancer-causing compounds. Isothiocyanates also seem to goad tumor cells into self-destruction, a process known as programmed cell death, or apoptosis. These activities appear in animal studies to be effective against a number of cancers.

Indole-3-carbinol (I3C) is another important biotransformation product that comes from broccoli, Brussels sprouts, cabbage and kale. I3C blocks breast cancer by interfering with tumor growth through its action on an enzyme that's necessary for cancer cell development. I3C also forms a compound with vitamin C, called ascorbigen, that has been found protective against colon cancer, Fortunately for us, Mother Nature has packaged vitamin C in vegetables such as broccoli that are also rich in I3C.

Garlic and Onions Other sources of sulfur include the edible members of the lily family. Chives, onions, shallots, garlic and leeks. Although all of these vegetables contain sulfur it's most concentrated in garlic and onions. The primary sulfur-rich phytochemicals in the vegetables are thiosulfonates. In uncut garlic and onions, there is no pungent sulfur smell. That's because it takes cutting, mashing, or bruising to convert thiosulfonates into strong-smelling products. Most cooks know how potent these compounds are, making our eyes sting and water when we prepare these foods.

Both garlic and onions have a long history of use as antifungal, antiviral and antibacterial agents. Recent scientific study, however, has concentrated on the cardiovascular benefits of garlic and onions. According to the German Commission E therapeutic monographs, garlic supports the cardiovascular system by lowering blood lipids, preventing platelet aggregation, prolonging clotting time, improving blood viscosity and preventing age-related vascular changes.

Garlic also has been found to lower high blood pressure. An analysis of eight clinical trials of people with high blood pressure and high blood lipids showed that those who were treated with garlic supplements reduced their systolic blood pressure, (the higher figure in blood pressure readings) by 7.7 points and their diastolic (the lower number) by 5 points. The benefits of eating garlic or taking supplements appear to be enhanced when patients also take fish oil capsules.

Garlic appears effective against several forms of cancer, especially stomach cancer. Some population studies in China have shown that those who do not regularly consume garlic have more stomach cancer than those who do. Garlic kills Helicobacter pylori, a bacteria that can cause stomach cancer. Researchers also suggest that garlic blocks tumor growth, boosts the immune system's resistance to cancer and deactivates chemical, bacterial and viral toxins that promote cancer. §

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No part of this article may be used for the promotion of product or services without the express written consent of the author. The information in this article is intended for educational purposes only. It is not intended to replace the advice of a health care provider. Nor is it to be used to diagnose, treat or cure any condition.