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Thanks to the Life Extension Foundation for this information
Cancer is, perhaps,
one of our greatest fears. Compounding our concern about contracting
the disease is the fear of treatment. Few medical treatments inflict so
much toxicity, mutilation and pain on the human body. Once a diagnosis
is made, a person's life will never be the same.
Even when treatment is successful, a person can
be disfigured from the effects, and parts of their body destroyed. The
chance of a recurrence is ever present and years after successful
treatment, cancer can come back even more virulent than before. Even
after enduring conventional therapy, a large number of cancer patients
still succumb from cancer cells that escaped the initial treatment.
A cancer diagnosis humbles a person of any
means. Hospital gowns don't look any better on rich people than they do
on poor, and chemotherapy feels the same. The degree of inconvenience,
disruption and destruction of not only the ill person's life, but of
those around them, should give any person pause to consider what they
can do to avoid it.
The National Cancer Institute (NCI) issued an
unprecedented number of press releases in the year 2002 stating that
diet has a major impact on cancer. Deleting things from one's diet, as
well as adding to it makes all the difference. What follows is some of
the research behind the NCI's announcements-research that is convincing
mainstream scientists to take another look at the anti-cancer benefits
of compounds that occur naturally.
What you choose to eat largely determines whether
or not you will get cancer. In his book Eat to Beat Cancer, J. Robert
Hatherill points out that Japanese smoke like crazy (more than
Americans), yet have the world's lowest rate of lung cancer. They also
have the greatest life expectancy on earth. Clearly, they're doing
something right. While there are many factors that affect longevity,
the one that researchers are currently focusing on is diet. We know
that diet plays a big role in cancer. It has been estimated that bad
diet is responsible for 60% of all cancers. A good diet can prevent 20%
to 50% of all cancers, according to most estimates.
What is a "good diet?" Research shows that it's a
diet high in plant-based foods (fruits, vegetables, grains, legumes). A
"bad diet" is one that's mostly animal-based foods (meat, dairy
products) and synthetic food (prepackaged "convenience" food). Plants
contain vitamins, minerals and phytochemicals that block, stop and
suppress cancer. Animal-based food contains the highest concentration
of cancer-causing chemicals that humans are exposed to, along with
saturated fat and lots of calories. "Convenience food" is more product
than food-full of calories, mostly devoid of nutrition. It's also
contaminated with many chemicals that make it look good on the shelf.
Research into diet and cancer is getting so
advanced that scientists are beginning to link what a person eats with
the type of cancer they get. Other researchers are going the other way:
pinpointing specific things in the diet that prevent cancer from
occurring. For example, researchers at the University of Utah
investigated the connection between carotenoids and colon cancer. They
found that lutein, but not other carotenoids, is associated with lower
risk. Similarly, researchers in the Netherlands found that folate,
vitamin C and beta-cryptoxanthin (but not lutein and other carotenoids)
are protective against lung cancer. The information from these kinds of
studies is stacking up.
Phytochemicals (naturally occurring in plants) are
the main defense against all types of cancer. As an example of how
powerful they can be, it was recently estimated that prostate cancer in
Greece could be reduced by two-fifths by merely increasing the
consumption of two things: tomatoes and olive oil. (Dairy products
should be simultaneously decreased, according to the report.) Another
group reports that over 51% of ovarian cancers could be avoided if
women would eat more green vegetables. This is an amazing figure. It
underscores the tremendous impact diet can have on cancer.
Phytochemicals have different actions and different
ways of protecting against cancer. Most are antioxidant, in other
words, they scavenge damaging free radicals. This action also protects
DNA. Others protect methylation which is critical for the activation of
cancer-suppressing genes. Still others enhance immunity or impede the
growth of abnormal cells.
Antioxidants and cancer
Human bodies are constantly exposed to chemicals,
radiation and other phenomena that generate free radicals. Free
radicals rip through cell membranes and slam into DNA, damaging it.
Cancer cells are essentially normal cells that contain damaged DNA.
Antioxidants stop free radicals and reduce DNA damage. This is why they
are a major defense against cancer.
All antioxidants are not all the same. Some are
better at stopping certain kinds of free radicals than others. For
example, I3C (indole-3-carbinol) and a supplement known as
"chlorophyllin" (a semi-synthetic version of chlorophyll) have
excellent effects against free radicals generated by chemicals called
heterocyclic amines. Heterocyclic amines are created when food,
especially meat, is cooked over high heat. Studies show that I3C and
chlorophyllin can stop this type of free radical up to 100%.
They can also protect against the
highly-carcinogenic mycotoxin known as "aflatoxin." Aflatoxin is
produced by a fungus that infects grains, notably corn. In studies on
rodents, both I3C and chlorophyllin inhibit liver cancer caused by this
toxin. A study from a region of China where the incidence of liver
cancer is very high shows that 100 mg of chlorophyllin three times a
day reduces DNA damage caused by aflatoxin by 55%. The researchers
predict that taking this supplement will push back the onset of this
type of cancer from 20 years to 40.
I3C and chlorophyllin work in another related way.
They keep the liver from metabolizing carcinogens, including
heterocyclic amines. It is the body's own metabolism of the chemicals
in its effort to detoxify them that makes them carcinogenic. I3C
apparently works through one type of enzyme, while chlorophyllin works
through another. A combination of the two may eliminate more radicals
than either alone.
Some antioxidants are better at preventing certain
types of cancer than others. Vitamin C, for example, can inhibit skin
cancer by 25% to 50% when applied directly to the skin. It does not
have the same effect against breast or prostate cancer. But lycopene, a
flavonoid from tomatoes, has antioxidant activity against prostate
cancer. Beta-carotene, a carotenoid, appears to protect against breast
cancer, but not against lung cancer. Having this type of information
about specific antioxidants can help a person choose one that may
target a certain type of cancer, or target a specific type of
carcinogen. For those without risk for any particular type of cancer or
exposure to any specific chemical, it would be prudent to take a
variety of anitoxidants in order to block as many types of free
radicals as possible.
Carotenoids and cancer
Studies show that people who eat a lot of red, orange, green and
yellow vegetables have a significantly decreased risk of various
cancers. The protective effect is due to carotenoids. Most people are
familiar with the carotenoid beta-carotene, found in carrots. There
are, however, hundreds of other carotenoids-some not even discovered
yet. There is lutein in spinach, zeaxanthin in corn and lycopene in
tomatoes. One of the purposes of carotenoids is to act as sunscreen for
the plants they occur in. It's not surprising then, that carotenoids
provide antioxidant protection, especially against free radicals
generated by radiation.
Lycopene is the most abundant carotenoid in humans. The prostate
gland alone contains 14 to 18 different metabolites of lycopene in
people who eat tomatoes or other vegetables that contain it. Studies
show that men who get the most lycopene in their diet have the lowest
risk of prostate cancer. The two largest studies involve 14,000
Seventh-Day Adventists (lacto-ovo vegetarians) and 47,894 American
physicians. In the physician study, men with the highest level of
lycopene in their blood had a 20% reduction in risk. In the Adventist
study, eating tomatoes more than five times a week reduced risk of
prostate cancer by 40%. Lycopene is good at protecting lymphocytes from
DNA damage. In an Italian study, 7 mg/day of lycopene reduced DNA
damage 50% in the first week.
Carotenoids work synergistically. Taking several together is better
than taking one alone. In the now infamous study where smokers took
beta-carotene supplements and nothing else, risk of lung cancer
actually rose. But a 30% reduction was found in a study of 100,000
people who ate a variety of carotenoids on a consistent basis rather
than just one. A 60% reduction was found in the same study for
non-smokers. It appears that alpha-carotene, not beta-carotene, is the
best carotenoid against lung cancer.
Folic acid and cancer
This vitamin has been involved in so many important cancer studies
that it stands in a class of its own. Folic acid (the vitamin version
of folate) is a B vitamin typically found in certain green vegetables
and legumes. Meat contains very little of it. A serving of steak, for
example, contains 3% of the RDA, while a serving of broccoli contains
50%.
Folate has powerful cancer preventive effects through its role in
maintaining methylation. Methylation has two powerful roles in
preventing cancer. First, it is crucial for the repair of mutations.
Second it is crucial for the activation and deactivation of genes
involved in cancer. Folate is one of the required factors for
methylation. Without it, methylation will fail, and cancer will result.
Abnormal methylation is present in all cancers, no matter the type. The
critical importance of folate, then, becomes apparent.
Lung and colon cancer are the first cancers to be linked to folate
deficiency. Breast, prostate and pancreatic cancer involve the
deficiency as well. Alcoholism, folate deficiency and breast cancer go
together. The same is true for colon cancer-alcoholism exacerbates
folate deficiency.
Research into the folate-cancer connection is just beginning. More
information about folate's cancer preventive effects will undoubtedly
emerge in the next few years.
Flavonoids and cancer
Quercetin, ellagic acid, apigenin and luteolin are powerful
anti-carcinogens from plants. These exotic-sounding phytochemicals
counteract cancer at its earliest stages. Apigenin, for example,
interferes with the way estrogen is metabolized. When apigenin is
present, estrogen stays in its weak form, unable to accelerate cancer
growth. Luteolin prevents cancer-promoting estrogen from getting into
cells. Several of the flavonoids suppress COX-2 (cyclooxygenase), an
enzyme that enables cancer to grow and spread. COX-2 has been in the
news because it's the enzyme targeted by certain antiinflammatories
that inhibit cancer and other degenerative diseases as well.
In addition to these cancer-blocking actions, flavonoids possess
powerful antioxidant activity that protects DNA from damage better than
vitamin C.
Some flavonoids come from the family of aromatic herbs and shurbs
known as labiatae. The labiatae include many of the herbs traditionally
regarded as medicinal such as rosemary, mint, lavender and thyme.
Labiatae plants provide a concentrated source of flavonoids with
anti-cancer properties. Scientific studies are beginning to prove that
flavonoids from these plants have very diverse and powerful effects
against cancer. For example, in a study on melanoma in mice, apigenin
and quercetin were equivalent to tamoxifen in inhibiting metastases. In
studies on human leukemia, luteolin and other flavonoids stopped the
growth of these cells in culture. Flavonoids can also inhibit enzymes
which enable cancer to invade surrounding tissue and spread to other
parts of the body.
Cancer-fighting flavonoids are also found in citrus fruit, tea and
other plant-based foods. Certain flavonoids in citrus fruit known as
polymethoxylated flavonoids work at the molecular level to counteract
cancer. Tangeretin, for example, restores cell communication so that
cancer can be brought under the body's control. Nobiletin, a similar
flavonoid, causes human leukemia cells to differentiate into normal
cells. Dozens of studies have been done showing that these flavonoids
have powerful and diverse effects against cancer cells. The net effect
is to wipe out cancer cells as soon as they appear.
Soybeans contain several types of
cancer-fighting phytochemicals. Soy isoflavones are non-steroidal plant
compounds that block hormone-related cancers. These so-called
"phytoestrogens" actually block estrogen from getting into cells, and
prevent hormone-related cancers including prostate and breast cancer.
In addition to their hormone-blocking effects, they also have powerful
antioxidant activity.
In a large study, men who drank soy milk more than once a day had a
70% reduced rate of prostate cancer. A similar study on women shows
that a soy-based diet, including 36 oz. of soymilk a day (113 to 207
mg/day of total isoflavones) reduced levels of 17-estradiol (strong
estrogen) by 25%.
Soy isoflavones may protect against bladder cancer. In a recent
study, genistein inhibited the growth of eight different types of human
bladder cancer cells. Daidzein and other isoflavones caused the cells
to self-destruct.
New research shows that phytoestrogens, including soy
phytoestrogens, shut down the activation of the estrogen receptor. This
receptor is provoked into sending "grow" signals when it encounters
chemical estrogens or estradiol (strong estrogen). In other words,
people with hormone-related cancers have too many estrogen "doorways"
on their cells. This results in a flood of strong estrogen into the
cell. This type of estrogen activates proliferation of the cell. Normal
cells have far fewer estrogen receptors. Normal cells also have an
equal number of a related receptor that phytoestrogens fit into and
activate. Cancer cells are missing this phytoestrogen receptor. The
phytoestrogen receptor acts as a counterbalance on the estrogen
receptor, preventing it from causing growth.
Tea
During the colonial era, most of North America was
owned by a monopoly called the East India Company. When the British
government, acting on behalf of the monopoly, granted it the exclusive
right to sell tea in America, forcing all other merchants out of
business, the colonists rebelled. The Boston Tea Party was the opening
act of the American Revolution. It's a testament to the power of tea
that it was instrumental in creating America. Tea has been used as
medicine since at least the Shang dynasty (1766-1122 B.C.).
Modern research confirms that tea has health
benefits, notably anti-cancer properties. Most of this research has
been done with green tea (which is minimally oxidized), rather than
other teas such as black tea. Tea contains several different
phytochemicals, including epigallocatechin-3-gallate (EGCG), a
polyphenol with proven biochemical actions against cancer. Tea also
contains vitamins A , C and E, a unique amino acid known as theanine,
carotene, zinc and many other cancer fighting substances.
One of the most striking studies on green tea was
done by a group of Japanese researchers on women who had been treated
for breast cancer. Analysis six years later of women with stage I or II
breast cancer showed that those who drank five or more cups of green
tea a day slashed their risk of recurrence almost in half. This is
equivalent to approximately 200 to 400 mg of EGCG. Furthermore, the
researchers found that the more green tea a woman drank before she got
cancer, the fewer metastases to lymph nodes she would have (if she was
premenopausal). Women who engage in the Japanese tea ceremony are half
as likely to die not only from breast cancer but from any cause,
according to researchers who followed them for eight years.
Two new studies show that green tea or EGCG
inhibits certain types of leukemia. When cells from adults with T-cell
leukemia are treated with green tea polyphenols or EGCG, the cancer
stops multiplying. Similarly, when various types of leukemia cells are
treated with EGCG, they self-destruct. According to the study's
authors, "Besides anticarcinogenic activity, EGCG is expected to have a
new function for leukemia therapy without side effects" (referring to
EGCG's ability to make existing cancer cells stop growing).
I3C
Indole-3-carbinol stands alone as the most well-studied natural
estrogen modulator. Found in cruciferous vegetables such as cabbage,
cauliflower and broccoli, I3C has proven effects against
hormone-related cancers.
I3C may be an important tool against environmentally-caused cancer
because it can block dioxin from entering cells. Dioxin is a chlorine
chemical, known as the most toxic chemical ever created-so toxic it is
measured in parts per trillion. The main source of it for most people
is meat and dairy products. Popular fast foods such as McDonald's Big
Macs® have been found to contain metabolites of dioxin. Dioxin is
suspected as a cause (or contributing cause) of breast, prostate,
lymphoma and lung cancers.
I3C comes to the rescue by its ability to compete with dioxin for
entry into cells. The same receptors, or doorways, that allow estrogen
and dioxin into cells, allow I3C as well. When I3C and dioxin are put
together with cells, I3C keeps some of the dioxin out by physically
blocking the harmful chlorine chemical. This same mechanism also
protects cells from strong estrogen that can promote cancer growth.
A recent study shows that treatment with I3C can reverse
precancerous conditions of the cervix in humans. I3C may also protect
smokers. When I3C was given to rats forced to ingest smoke, DNA damage
was reduced over 50% in lungs and trachea, and 65% in the bladder. It
also inhibits heterocyclic amines, dangerous carcinogens that form when
meat is cooked. One study showed that I3C was up to 95% effective in
inhibiting carcinogens. (Note: the recommended dose for I3C is 400 mg
for most women and 600 mg for most men, depending on weight).
Zinc
Zinc is crucial for immunity. Thirty days of suboptimal zinc intake
causes a 30% to 80% loss of immune defense. Studies show that zinc is
important for natural killer (NK) cells to multiply and function. NK
cells are the body's first-line defense against certain types of
cancer. Supplemental zinc has been shown to increase antibody response
and T-cell counts. Zinc deficiency causes the thymus to atrophy:
supplements can reverse this.
Think Prevention
Cancer is the second
leading cause of death in America. The time to think about prevention
is now. Eliminating chemical exposure (yard sprays, household cleaners,
paint, plastic, etc.) as much a possible reduces risk. Changing from a
meat-based diet to plant-based food can slash risk by as much as 50%.
Certain types of supplements can further reduce risk by terminating
cancer before it has a chance to grow and spread.
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Zinc status is very much related to infection and disease. People
with lymphoma have decreased levels of zinc and increased levels of
copper. This trend reverses during remission. Zinc deficiency is
prevalent in alcoholism, gastrointestinal disorders and renal disease.
Infections appear to reduce zinc levels. And reduced zinc levels appear
to increase the chances of getting an infection.
It's impossible to make a blanket recommendation about how much zinc
a person should take. Too much zinc is as bad as too little. Too much
zinc depresses immunity as surely as too little. Very little research
has been done on zinc, and unfortunately, "There is no universally
accepted single measure suitable to accurately assess the zinc status
of an individual."* Currently, 30 to 50 mg of elemental zinc per day is
the recommended amount. However, this is very arbitrary inasmuch as an
individual might need different amounts of zinc at different times,
depending on their health, age, diet and other factors that affect zinc
utilization, absorption and acquisition. As an example of how difficult
pinpointing zinc supplementation can be, a study on healthy men showed
that 300 mg/day of elemental zinc suppressed immunity. Yet, a study in
people over age 70 found that 440 mg of zinc a day significantly
increased immunity. One approach is to look at copper levels instead.
If copper levels are elevated, or the copper-to-zinc ratio is high,
zinc should be taken until the balance normalizes, regardless of
whether lab results fall within the "normal" range.
Anti-inflammatories
Non-steroidal anti-inflammatory drugs (NSAIDs) exploded on the scene
in 2000 as possible cancer preventive agents. The latest research
indicates that NSAIDs, including aspirin, have multiple and diverse
actions against the growth and mestastasis of cancer cells. Colon
cancer has received the most attention. Risk can be slashed 50% by the
long-term use of NSAIDs such as ibuprofen. Esophageal, stomach, rectal
and bladder cancer risk are also significantly reduced. For breast
cancer, 2 to 10 years of NSAIDs reduces overall risk, and reduces the
risk of metastases everywhere except nearby lymph nodes.
Aspirin may also reduce risk, but apparently in a different way, and
not as strongly. When researchers at the University of Leeds tested
aspirin on colon cancer cell lines, it stopped the cells from growing
but did not induce apoptosis (cell death). The same cells treated with
the NSAID drug indomethacin were growth-arrested and destroyed by
apoptosis. Different NSAIDs work differently against cancer cells, and
it may turn out that some work better for some types of cancers than
others. Combining aspirin with an NSAID may enhance the effectiveness.
The natural anti-inflammatory, curcumin, has demonstrated similar
and powerful effects against the growth of cancer cells. Some new
concerns have been raised about the expensive and highly advertised
NSAIDs, Celebrex and Vioxx drugs. According to the drug reference book
Worst Pills, Best Pills, they may have previously unknown
gastrointestinal and cardiovascular side-effects. The manufacturers of
both drugs have been warned by the FDA to cease misrepresenting their
safety and effectiveness.
One of the interesting properties about anti-inflammatories is that
they may conserve the body's antioxidants, particularly the
carotenoids. In a study from the UK, 1200 mg/day of ibuprofen helped
cancer patients recover their levels of beta-carotene, lutein and
lycopene. This phenomenon can be explained by the fact that
inflammatory reactions generate free radicals that deplete the body of
such plant-derived antioxidants. Anything that suppresses inflammation,
be it ibuprofen, fish oil or curcumin, conserves precious antioxidants
in the body. Chronic inflammation is related to increased cancer risk,
and inflammation enhances the ability of cancer to spread.
Supplements versus food
Food contains all the nutrients the human body needs. And if we eat
the right kind of food, we'll get them. The problem is we don't. Some
of us, however, are chasing our hot dogs with vitamins in an effort to
fortify our diets. That's the approach of the industry that makes food
products-they fortify their products with vitamins. It's not the
greatest approach, but it's not altogether bad. Vitamins can undo some
of our bad habits. They can't replace good diet, but they can have a
beneficial effect.
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And in fact, sometimes a supplement gets the job done better than a
food containing it. The reason is partly due to bioavailability.
Bioavailability has to do with the body's ability to utilize a
nutrient. The vitamins in food are attached to proteins. They must be
separated from those proteins in order to be utilized. Different
factors can conspire to impede that process. For example, phytic acid
that is found in the hulls of grains like wheat can interfere with the
body's absorption of zinc and calcium. Another classic example is the
necessity of a stomach chemical known as intrinsic factor for vitamin
B12 utilization. And then there's the problem of how various things a
person eats interact. A person who dresses their salad with non-fat
dressing will not be able to utilize the vitamin K in the leaves of the
lettuce: fat must be present for the vitamin to be absorbed.
Supplements avoid these problems. Vitamin K supplements, for example,
come ready-made with a drop of oil for absorption. The bioavailability
problem has been demonstrated in studies showing that if Indonesian
women eat a beta-carotene-fortified cracker, more beta-carotene and
vitamin A will appear in their blood than if they eat stir-fried
vegetables containing beta-carotene.
Folate is another vitamin that seems more bioavailable as a
supplement. Research in the UK shows that "intake of folic acid
supplements provides a greater elevation in serum folate levels than
dietary food intake, suggesting that dietary manipulation is an
ineffective strategy (for pregnant women)." This agrees with data from
the Nurses' Health Study where folate from food lowered the risk of
colon cancer a little, but supplemental folate lowered it significantly.
This highlights one of the other benefits of supplements. They are
concentrated and you know how much you're getting (if the supplement is
from a reputable company). One of the problems with trying to get
enough cancer-fighting nutrients from food is that the sheer amount of
vegetables and fruit a person has to consume is daunting if the person
wants to get a full spectrum of protection, not just avoid deficiency
disease. For example, if a person wanted to cover all the carotenoids
every day, they would need to eat green, yellow, orange and red
vegetables-all of them. Let's say they also wanted the benefits of I3C
(indole-3-carbinol), a phytochemical in cruciferous vegetables, they
would have to add cabbage, broccoli, cauliflower or mustard. If they
also wanted to cover the citrus flavonoid spectrum, they would also
have to eat a wide variety of citrus fruit-and so on. If a person wants
to ingest a wide variety of anti-cancer compounds on a daily basis, in
a substantial amount, it's more practical to take them in a
concentrated form. A person can hold in one hand vitamins found in
bushels of vegetables, pounds of soy and mountains of fruit. However,
supplements should not replace a good diet. Whole foods contain
important and diverse factors that maintain health, and everyone should
be eating as much of them as possible. Supplemental vitamins can,
however, provide an extra measure of protection. For cancer prevention,
this is especially important.
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