Grapefruits, like oranges and other citrus fruits, contain monoterpenes, believed to help prevent cancer by sweeping carcinogens out of the body. Some studies show that grapefruit may inhibit the proliferation of breast-cancer cells in vitro. They also contains vitamin C, beta-carotene, and folic acid.
Grapes, red contain bioflavonoids, powerful antioxidants that work as cancer preventives. Grapes are also a rich source of resveratrol, which inhibits the enzymes that can stimulate cancer-cell growth and suppress immune response. They also contain ellagic acid, a compound that blocks enzymes that are necessary for cancer cells – this appears to help slow the growth of tumors.
Studies show that consumption of green and yellow leafy vegetables has been associated with lower levels of stomach cancer.
Kale has indoles, nitrogen compounds which may help stop the conversion of certain lesions to cancerous cells in estrogen-sensitive tissues. In addition, isothiocyanates, phytochemicals found in kale, are thought to suppress tumor growth and block cancer-causing substances from reaching their targets.
Licorice root has a chemical, glycyrrhizin, that blocks a component of testosterone and therefore may help prevent the growth of prostate cancer. However, excessive amounts can lead to elevated blood pressure.
Mushrooms – There are a number of mushrooms that appear to help the body fight cancer and build the immune system – Shiitake, maitake, reishi, Agaricus blazei Murill, and Coriolus Versicolor. These mushrooms contain polysaccharides, especially Lentinan, powerful compounds that help in building immunity. They are a source of Beta Glucan. They also have a protein called lectin, which attacks cancerous cells and prevents them from multiplying. They also contain Thioproline. These mushrooms can stimulate the production of interferon in the body.
Extracts from mushrooms have been successfully tested in recent years in Japan as an adjunct to chemotherapy. PSK is made from the Coriolus Versicolor. Maitake mushroom extract is PCM4.
Nuts contain the antioxidants quercetin and campferol that may suppress the growth of cancers. Brazil nut contains 80 micrograms of selenium, which is important for those with prostate cancer. (Note: Many people are allergic to the proteins in nuts, so if you have any symptoms such as itchy mouth, tight throat, wheezing, etc. after eating nuts, stop. Consider taking a selenium supplement instead or work with someone on how to eliminate this allergy.)
Oranges and lemons contain Iimonene which stimulates cancer-killing immune cells (lymphocytes, e.g.) that may also break down cancer-causing substances.
Papayas have vitamin C that works as an antioxidant and may also reduce absorption of cancer-causing nitrosamines from the soil or processed foods. Papaya contains folacin (also known as folic acid), which has been shown to minimize cervical dysplasia and certain cancers.
Raspberries contain many vitamins, minerals, plant compounds and antioxidants known as anthocyanins that may protect against cancer. According to a recent research study reported by Cancer Research 2001;61:6112-6119, rats fed diets of 5% to 10% black raspberries saw the number of esophageal tumors decrease by 43% to 62%. A diet containing 5% black raspberries was more effective than a diet containing 10% black raspberries. Research reported in the journal Nutrition and Cancer in May 2002 shows black raspberries may also thwart colon cancer. Black raspberries are rich in antioxidants, thought to have even more cancer-preventing properties than blueberries and strawberries.
Seaweed and other sea vegetables contain beta-carotene, protein, vitamin B12, fiber, and chlorophyll, as well as chlorophylones – important fatty acids that may help in the fight against breast cancer. Many sea vegetables also have high concentrations of the minerals potassium, calcium, magnesium, iron, and iodine.
Soy products like tofu contain several types of phytoestrogens — weak, nonsteroidal estrogens that could help prevent both breast and prostate cancer by blocking and suppressing cancerous changes. There are a number of isoflavones in soy products, but research has shown that genistein is the most potent inhibitor of the growth and spread of cancerous cells. It appears to lower breast-cancer risk by inhibiting the growth of epithelial cells and new blood vessels that tumors require to flourish and is being scrutinized as a potential anti-cancer drug. However, there are some precautions to consider when adding soy to your diet. Eating up to 4 or 5 ounces of tofu or other soy a day is probably ok, but research is being done to see if loading up on soy could cause hormone imbalances that stimulate cancer growth. As a precaution, women who have breast cancer or are at high risk should talk to their doctors before taking pure isoflavone powder and pills, extracted from soy.
Sweet potatoes contain many anticancer properties, including beta-carotene, which may protect DNA in the cell nucleus from cancer-causing chemicals outside the nuclear membrane.
Teas: Green Tea and Black tea contain certain antioxidants known as polyphenols (catechins) which appear to prevent cancer cells from dividing. Green tea is best, followed by our more common black tea (herbal teas do not show this benefit). According to a report in the July 2001 issue of the Journal of Cellular Biochemistry, these polyphenols that are abundant in green tea, red wine and olive oil, may protect against various types of cancer. Dry green tea leaves, which are about 40% polyphenols by weight, may also reduce the risk of cancer of the stomach, lung, colon, rectum, liver and pancreas, study findings have suggested.
Tapioca is derived from the cassava plant. It is one of the many plants that manufactures cyanide by producing a chemical called linamarine which releases hydrogen cyanide when it is broken down by the linamarase enzyme. Spanish researches have been studying the cassava and attempting to clone the genes from the plant which are responsible for producing the hydrogen cyanide and then transfer it to a retrovirus. However, funding for the project has run out.http://news.bbc.co.uk/hi/english/health/newsid_317000/317467.stm for more information on this. For a list of other foods that contain B17, go to our laetrile page.
Tomatoes contain lycopene, an antioxidant that attacks roaming oxygen molecules, known as free radicals, that are suspected of triggering cancer. It appears that the hotter the weather, the more lycopene tomatoes produce. They also have vitamin C, an antioxidant which can prevent cellular damage that leads to cancer. Watermelons, carrots, and red peppers also contain these substances, but in lesser quantities. It is concentrated by cooking tomatoes. Scientists in Israel have shown that lycopene can kill mouth cancer cells. An increased intake of lycopene has already been linked to a reduced risk of breast, prostate, pancreas and colorectal cancer. (Note: Recent studies indicate that for proper absorption, the body also needs some oil along with lycopene.)
Tumeric (curcuma longa), a member of the ginger family, is believed to have medicinal properties because it inhibits production of the inflammation-related enzyme cyclo-oxygenase 2 (COX-2), levels of which are abnormally high in certain inflammatory diseases and cancers, especially bowel and colon cancer. In fact, a pharmaceutical company Phytopharm in the UK hopes to introduce a natural product, P54, that contains certain volatile oils, which greatly increase the potency of the turmeric spice.
Turnips are said to contain glucose molaes which is a cancer fighting compound. I haven’t confirmed this.
Consumption of fruits and vegetables has been associated with decreased risk of cancers of the colon and rectum.