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Basically polyphenols tend to contain ring structures that have a lot of electron density around them. They are thus easily able to either absorb or donate some electron density to a free radical, leaving the free radical unable to attack another molecule.

Free radicals are highly reactive species, containing unpaired electrons. They use these unpaired electrons to attack bonds in other molecules. In the worst case scenarios, this leads to breaks in the DNA, mutations, cancer and other diseases.

Cancer Fighting Foods/Spices

The National Cancer Institute estimates that roughly one-third of all cancer deaths may be diet related. What you eat can hurt you, but it can also help you. Many of the common foods found in grocery stores or organic markets contain cancer-fighting properties, from the antioxidants that neutralize the damage caused by free radicals to the powerful phytochemicals that scientists are just beginning to explore. There isn't a single element in a particular food that does all the work: The best thing to do is eat a variety of foods.

The following foods have the ability to help stave off cancer and some can even help inhibit cancer cell growth or reduce tumor size.

Avocados are rich in glutathione, a powerful antioxidant that attacks free radicals in the body by blocking intestinal absorption of certain fats. They also supply even more potassium than bananas and are a strong source of beta-carotene. Scientists also believe that avocados may also be useful in treating viral hepatitis (a cause of liver cancer), as well as other sources of liver damage.

Broccoli, cabbage, and cauliflower have a chemical component called indole-3-carbinol that can combat breast cancer by converting a cancer-promoting estrogen into a more protective variety. Broccoli, especially sprouts, also have the phytochemical sulforaphane, a product of glucoraphanin - believed to aid in preventing some types of cancer, like colon and rectal cancer. Sulforaphane induces the production of certain enzymes that can deactivate free radicals and carcinogens. The enzymes have been shown to inhibit the growth of tumors in laboratory animals. However, be aware that the Agriculture Department studied 71 types of broccoli plants and found a 30-fold difference in the amounts of glucoraphanin. It appears that the more bitter the broccoli is, the more glucoraphanin it has. Broccoli sprouts have been developed under the trade name BroccoSprouts that have a consistent level of sulforaphane - as much as 20 times higher than the levels found in mature heads of broccoli.

Carrots contain a lot of beta carotene, which may help reduce a wide range of cancers including lung, mouth, throat, stomach, intestine, bladder, prostate and breast. Some research indicated beta carotene may actually cause cancer, but this has not proven that eating carrots, unless in very large quantities - 2 to 3 kilos a day, can cause cancer. In fact, a substance called falcarinol that is found in carrots has been found to reduce the risk of cancer, according to researchers at Danish Institute of Agricultural Sciences (DIAS). Kirsten Brandt, head of the research department, explained that isolated cancer cells grow more slowly when exposed to falcarinol. This substance is a polyacethylen, however, so it is important not to cook the carrots.

Chili peppers and jalapenos contain a chemical, capsaicin, which may neutralize certain cancer-causing substances (nitrosamines) and may help prevent cancers such as stomach cancer.

Cruciferous vegetables - broccoli, cauliflower, kale, Brussels sprouts, and cabbage contain two antioxidants, lutein and zeaxanthin that may help decrease prostate and other cancers.

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