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.
Figs apparently have a derivative of benzaldehyde. It has been
reported that investigators at the Institute of Physical and Chemical Research
in Tokyo say benzaldehyde is highly effective at shrinking tumors, though I
haven't seen this report. In addition, the U.S. Department of Agriculture says
figs, which contain vitamins A and C, and calcium, magnesium and potassium, may
curtail appetite and improve weight-loss efforts. Fig juice is also a potent
bacteria killer in test-tube studies.
Flax contains lignans, which may have an antioxidant effect and
block or suppress cancerous changes. Flax is also high in omega-3 fatty acids,
which are thought to protect against colon cancer and heart disease. See Budwig diet
for a specialized diet using flax seed oil and cottage cheese. For studies
about flax seed and flax oil, go to our Important News
or Archives Page.
Garlic has immune-enhancing allium compounds (dialyl sultides)
that appear to increase the activity of immune cells that fight cancer and
indirectly help break down cancer causing substances. These substances also
help block carcinogens from entering cells and slow tumor development. Diallyl
sulfide, a component of garlic oil, has also been shown to render carcinogens
in the liver inactive. Studies have linked garlic — as well as onions, leeks,
and chives — to lower risk of stomach and colon cancer. Dr. Lenore Arab,
professor of epidemiology and nutrition at the UNC-CH (University of North Carolina
at Chapel Hill) schools of public health and medicine and colleagues analyzed a
number of studies and reported their findings in the October 2000 issue of the
American Journal of Clinical Nutrition. According to the report, people who
consume raw or cooked garlic regularly face about half the risk of stomach
cancer and two-thirds the risk of colorectal cancer as people who eat little or
none. Their studies didn't show garlic supplements had the same effect. It is
believed garlic may help prevent stomach cancer because it has anti-bacterial
effects against a bacterium, Helicobacter pylori, found in the stomach and
known to promote cancer there.
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.
Red wine, even without alcohol, has polyphenols that may protect
against various types of cancer. Polyphenols are potent antioxidants, compounds
that help neutralize disease-causing free radicals. Also, researchers at
the University of North Carolina's medical school in Chapel Hill found the
compound resveratrol, which is found in grape skins. It appears that
resveratrol inhibits cell proliferation and can help prevent cancer. However,
the findings didn't extend to heavy imbibers, so it should be used in
moderation. In addition, alcohol can be toxic to the liver and to the nervous
system, and many wines have sulfites, which may be harmful to your health.
Note: some research indicates that alcohol is considered a class
"A" carcinogen which can actually cause cancer - see http://www.jrussellshealth.com/alccanc.html.
You should probably switch to non-alcoholic wines.
Rosemary may help increase the activity of detoxification enzymes.
An extract of rosemary, termed carnosol, has inhibited the development of both
breast and skin tumors in animals. We haven't found any studies done on humans.
Rosemary can be used as a seasoning. It can also be consumed as a tea: Use 1
tsp. dried leaves per cup of hot water; steep for 15 minutes.
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.
There are many good books on this
topic, including Vern Verona's book on "Cancer Fighting Foods."