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Cancer is growing a an alarming rate, but cancer can be prevented if you know how.
This is an excerpted from "Fantastic Voyage: Live Long Enough to Live Forever"
Let's move now from early
detection and determination of genetic risk to cancer prevention. An
effective program for avoiding cancer in the first place entails diet
and nutrition, lifestyle modification, and chemoprevention.
Diet and Nutrition
Thinking has changed since 1949, when the
American Medical Association stated, "There is no scientific evidence
that food or other nutritional essentials are of any specific value in
the control of cancer." Diet, lifestyle, and nutrition have actually
been shown to play an important role in determining cancer risk. For
instance, research indicates that populations that consume large
quantities of plant-derived foods have a lower incidence of several
types of cancer. In 1991, the National Cancer Institute incorporated
these findings into the 5 a Day for Better Health Program. It
recommended five daily servings of fruits and vegetables as part of a
low-fat, high-fiber diet. Despite widespread promotion of this program
over the past decade, fewer than one in five American children and
fewer than one in four adults eat five portions of produce a day, a
statistic that hasn't changed in 10 years. Ray & Terry's Longevity
Program regards the 5 a Day program as a good start, but we recommend
our 5-to-10-a-Day program, encouraging five to seven servings of vegetables and zero to three servings of fruit daily.
See Pay & Terry's Food Pyramid on page 106. Emphasis should be on
low-glycemic-load (low-starch) vegetables - typically, green vegetables
as opposed to higher-carbohydrate root vegetables. Fruit is beneficial,
but caution is needed - while it's almost impossible to eat too many
low-starch vegetables, you can eat too much fruit and consume excessive
sugar.
Some people feet
that by taking nutritional supplements, they can compensate for a diet
insufficient in plant-based foods. While supplements are clearly of
proven value, taken alone they do not offer sufficient protection
against cancer. A diet rich in naturally occurring nutrients, as found
in fruits and vegetables, is needed for optimal cancer prevention. Our
dietary recommendations include:
Drink vegetable juice. Start your day right with an
8-to-12-ounce glass of freshly squeezed vegetable juice as part of, or
instead of, breakfast: juice some cucumber, broccoli, kale, cabbage, a
carrot (for flavor, but not more than one, to avoid excess sugar), and
other green vegetables you find in your refrigerator. This can provide
almost half of your 5-to-10-a-Day requirements even before you leave
your house in the morning. We also re-emphasize the importance of
eating organic produce whenever possible to minimize exposure to pesticides and other carcinogenic chemical residues.
Eat a Mediterranean diet. The Mediterranean diet, which is low
in red meat and emphasizes whole grains, fish, and fresh fruits and
vegetables, has been associated with reduced cancer risk.
Digestive-tract cancers (mouth, esophagus, stomach, and colon) and
cancers of the lung and prostate are lower. In a recent study of more
than 22,000 Greeks, those who followed the Mediterranean diet had a 24
percent decrease in total incidence of cancer, compared with
individuals who did not eat this way. The Mediterranean diet includes
generous amounts of extra virgin olive oil, which protects against
several types of cancer - colon, breast, and skin - as well as coronary
heart disease. The Mediterranean diet also calls for large portions of
fresh tomatoes and tomato sauces. Cooked tomatoes, along with most
other red fruits and vegetables, are rich in the bioflavonoid lycopene,
which has been associated with a lower risk of prostate cancer.
Avoid the white Satan - sugar. Because cancer cells consume
sugar so avidly, the PET scan used by doctors to locate cancer in the
body involves giving patients radioactive glucose (or sugar), which is
concentrated in areas harboring malignancies and shows up as hot spots
on the scan. The 1931 Nobel laureate Otto Warburg demonstrated that
cancer cells have a fundamentally different metabolism than normal
cells and utilize sugar as their predominant food for growth. You can
inhibit cancer formation by avoiding dietary sources of simple sugar as
well as foods with a high glycemic load, which are rapidly converted to
sugar in the body.
A direct relationship between sugar consumption and pancreatic cancer
was seen in women who participated in the Nurses' Health Study. The
Women's Health Study, published by researchers at UCLA in 2004, found
that a high-glycemic-load diet significantly increased risk of
colorectal cancer. When coupled with excess weight and a sedentary
lifestyle, women in this study who consumed excess sugar had more than
three times the average risk of developing cancer of the pancreas.
Avoid "the white Satan" whenever and wherever possible.
Lifestyle Modification
Exercise. Exercise has been associated with a lower incidence of
cancer, while a sedentary lifestyle increases cancer risk. We are in
favor of the following American Cancer Society recommendations:
• Adults should engage in moderate (or even more vigorous)
activity for a minimum of 150 minutes a week. This can be done as three
50-minute sessions, multiple 10-minute sessions, or any combination to
total two and a half hours a week.
• Children and adolescents should engage in at least 60 minutes of moderate-to-vigorous physical activity almost every day.
It is often good to perform your exercise in the great outdoors.
Sunlight exposure is itself protective against many types of cancer.
UVB (ultraviolet B) radiation found in sunlight is associated with
reduced risk of cancer of the breast, colon, ovary, prostate, and
lymphoma. Lower mortality rates are seen with higher amounts of UVB
exposure for cancers of the bladder, esophagus, kidney, lung, pancreas,
rectum, and stomach. Sunscreen interferes with absorption of UVB
radiation, so we disagree with conventional recommendations that people
should use sunscreen whenever they're outside. Unless you're someone
who sunburns easily, such as people with very fair complexions and
redheads, we recommend you use don't use sunscreen all the time.
Instead, apply it primarily when risk of sun damage is high: during
midday in summer, at high altitudes, or during any prolonged exposure
to intense sunlight, such as when boating or skiing on a bright day.
Better yet, cover up exposed skin with clothing or avoid midday
direct sun exposure if possible. Regular exposure of skin to
non-burning sunlight is itself cancer-protective. Increased consumption
of fish and the omega-3 fatty acids EPA and DHA (along with decreased
consumption of omega-6 fatty acids such as from corn oil and safflower
oil) can be very protective against melanoma, the most dangerous form
of skin cancer, which has been associated with excessive sun exposure.
Avoid pesticides. Exposure to agricultural chemicals has been
linked to numerous cancers. Agricultural workers are at higher risk of
cancers of the stomach (40 percent increased risk), rectum (50
percent), larynx (40 percent), and prostate (40 percent). The increased
risk of prostate cancer was specifically related to application of
pesticides (70 percent increased risk). Again, we stress the importance
of eating organically grown foods whenever possible.
Lose excess body weight. Being overweight or obese is an
independent risk factor for several types of cancer, a fact that is not
widely known. A survey conducted by the American Cancer Society in 2002
revealed that only 1 percent of the American public realizes that
maintaining a healthy weight reduces cancer risk. Yet according to the
Centers for Disease Control and Prevention, as of the year 2000, 64
percent of American adults were overweight and about 30 percent were
obese. A recent study published in the New England Journal of Medicine
prospectively followed more than 900,000 American adults to assess the
relationship between weight and cancer risk. This study showed that
being overweight or obese accounted for 20 percent of cancer deaths in
women and 14 percent in men. Obesity was specifically linked to cancers
of the liver, pancreas, prostate, and cervix, non-Hodgkin lymphoma, and
multiple myeloma.
Avoid tobacco. It has been more than 40 years since the first
report of the Surgeon General's Advisory Committee on Smoking and
Health was released on January 11, 1964. Thanks to widespread
dissemination of information linking smoking to multiple health risks,
including cancer, emphysema, and heart disease, the percentage of
Americans who smoke has decreased significantly. This downward trend is
most prominent among American men: 52 percent smoked in 1965, but only
28 percent smoke currently. Thirty-four percent of American women
smoked in 1965, while 22 percent do today. Unfortunately, smoking rates
in the United States have remained flat for several years, with little
decrease since 1990.
The list of illnesses linked to cigarette smoking reads like
the little black book of the Angel of Death. Cigarette smoke increases
risk of cancer of all the tissues tobacco smoke touches on its way into
the body (lung, mouth, throat, and larynx), on its way out of the body
(kidney and bladder), and some places in between (cervix and pancreas).
Cardiovascular diseases, including heart attack, sudden cardiac death,
and stroke, are increased dramatically in individuals who smoke. Lung
problems such as emphysema, asthma, chronic bronchitis, and COPD
(chronic obstructive pulmonary disease) are all much higher among
smokers. And this is only a partial list!
Smoking cessation is a fundamental part of any
cancer-prevention program. There are a number of medications and
therapies now available to help smokers kick the habit. If you still
smoke, we strongly advise that you implement a smoking-cessation
program immediately.
Chemoprevention
"Chemoprevention" refers to the use of
natural or synthetic substances to reduce the risk of cancer. A number
of naturally occurring nutrients are chemoprotective, including
vitamins, minerals, herbs, antioxidants, and hormones. While
insufficient to prevent cancer by themselves, the following natural
chemoprotective agents are a valuable part of a comprehensive
cancer-prevention program. Other chemoprotective agents are discussed
in chapter 21, "Aggressive Supplementation."
Vitamin C. Linus Pauling, the only scientist ever to receive two
unshared Nobel prizes, was so impressed with the ability of vitamin C
to both prevent and treat cancer that he coauthored a book on the
subject. Vitamin C, particularly when combined with the mineral
selenium, can induce cells that are "on the way" to becoming cancerous
to turn back from "the dark side" and remain benign. Estimates of
optimal doses of vitamin C vary between 1 and 10 grams per day. Our
program recommends that most adults take 2 grams (2,000 milligrams) of
vitamin C daily for chemoprevention.
Selenium. There are four well-known antioxidant "ACES": three
are vitamins (A, C, and E), one is a mineral (selenium). Selenium is
the mineral cofactor that activates the powerful antioxidant enzyme
GSH-Px (glutathione peroxidase). In the Nutritional Prevention of
Cancer trial, selenium supplementation reduced the total incidence of
cancer, particularly cancer of the prostate. We recommend a
chemopreventive dose of 400 to 600 micrograms of selenium daily.
Coenzyrne Q10. Coenzyme Q10 is critically
involved in energy generation within the mitochondria of the cell.
Malignant tissues in the body create increased levels of free radicals.
Antioxidant enzymes are under increased stress when attempting to
control the free-radical damage found in cancerous tumors. The
metabolic needs of these protective enzymes increase dramatically, and
coenzyme Q10 is vital in helping to provide them with the energy needed to fight cancer.
Breast tumors have dramatically decreased levels of coenzyme Q10 as a result of free-radical stress, and breast-cancer patients are typically given large doses of supplemental coenzyme Q10 by nutritional physicians. Coenzyme Q10
has numerous other protective effects in the body, including lowering
blood pressure and protecting the heart. We recommend that healthy
adults take from 60 to 200 micrograms of coenzyme Q10 a day.
Curcumin. This herb, derived from turmeric (a common spice), has
been used in Ayurvedic and Chinese medicine for centuries. Curcumin has
powerful anti-inflammatory properties and arrests the growth of cancer
cells at the G2 stage of their cell division. Combining curcumin with
ECGC (epigaRocatechin-3-gallate) from green tea provides synergistic
cancer prevention.
Curcumin fights growth of cancer cells in at least a dozen
separate ways. It blocks estrogen-mimicking chemicals like pesticides
from causing excessive stimulation of hormonally sensitive tissues such
as those in the breast and prostate. In this way, it works in harmony
with other phytonutrients that have similar actions, such as soy
isoflavones and cruciferous vegetables.
Curcumin is used as a natural anti-inflammatory to treat
patients with inflammatory conditions such as arthritis. It blocks the
COX (cyclooxygenase) enzyme, which creates inflammation in the body. It
is well known that colon cancer has a significant inflammatory
component and that patients who take COX inhibitors such as aspirin
have a reduced incidence of colon cancer. Studies have shown that
taking curcumin can also help prevent colon cancer.
We encourage the regular use of the spice turmeric, which
contains curcumin, in food preparation, as well as taking 900
milligrams of supplemental curcumin a day for cancer prevention.
Melatonin. Many people know that melatonin can help with sleep.
A few people also know that it is a powerful anti-aging hormone. Fewer
yet are aware of the fact that melatonin has an important role as a
cancer-protective agent. One paper reviewed 27 studies on the use of
melatonin as a cancer preventive or treatment. The authors concluded
that "melatonin could indeed be considered a physiological anticancer
substance."
Many studies have centered on the use of melatonin in the
prevention and treatment of breast cancer. Melatonin can directly
inhibit the growth of breast-cancer cells. It also has important
antioxidant and immunostimulatory effects. We recommend taking 0.1 to 3
milligrams of this naturally occurring chemopreventive agent daily, at
bedtime.
Folic acid. As discussed in chapter 13, folic acid is intimately
involved in numerous methylation reactions. These include synthesis of
DNA, turning genes within the cell on or off, and detoxification of
chemical toxins. Abnormalities in all of these reactions have been
linked to the risk of malignancy. Recently, folic acid deficiency has
been implicated as a risk factor for developing cancer. In a review
article of 34 studies on the connection between folic acid and cancer,
a direct link was found between low folic acid levels and cancers of
the colon and breast.
Folic acid, which is important for both heart health and cancer
protection, is one of the few nutrients that works better when taken as
a separate supplement than as part of food. A minimum of 800 micrograms
per day is recommended, but depending on other factors (such as
homocysteine level), this can be raised to 5,000 to 10,000 micrograms
or more.
EPA/DHA. The cardiac benefits of the essential fatty acid
derivatives EPA (eicosapentaneoic acid) and DRA (docosahexaneoic acid)
are well known, but these "fish oils" also play important roles as
naturally occurring chemoprotective agents. Like curcumin, fish oils
possess an anti-inflammatory action that is the basis of the
cancer-protective effect. As discussed in chapter 12, EPA and DHA are
naturally occurring COX-2 inhibitors. COX-2 is an enzyme that increases
levels of inflammatory chemicals in the body such as PG E2
(prostaglandin E2) and is found in high levels in precancerous and
cancerous tissues. Increased levels of both COX-2 and PG E2 have been
found in cancers associated with inflammation, such as breast and colon
cancer. Consumption of cold-water fish, which is rich in EPA and DHA,
as well as EPA/DHA supplementation, is anti-inflammatory,
cardioprotective, and chemoprotective.
We recommend a minimum of 1,000-3,000 milligrams of EPA and 700-2,000 milligrams of DHA daily.
Beta-carotene (a special case). Not all vitamins are
cancer-protective - at least, not for all people. In particular, the
Finnish Alpha-Tocopherol, Beta Carotene (ATBC) Cancer Prevention Study
showed that supplementation with beta-carotene actually increased the
incidence of lung cancer when taken in supplement form by cigarette
smokers. Several other studies have confirmed this association, so we
recommend that people at increased risk of lung cancer (such as smokers
or workers exposed to asbestos) not take supplemental beta-carotene.
Here's the solution for anyone seriously concerned about cancer
prevention: if you smoke, stop. Stop today, right now. But if for
whatever reason you are unable to quit, don't take supplemental
beta-carotene. Between early-detection tests and preventive and
treatment strategies, it is likely that the death rate from cancer will
soon begin to plummet and, in the near future, cancer will no longer be
the gruesome killer that it is today.
Secrets of Soy and the Japanese Diet
Besides possessing a lower incidence of heart disease and
menopausal symptoms, the Japanese also appear to have less cancer. This
is due in part to their greater consumption of soybean-based foods such
as soy milk, tofu, and soybeans. The soy isoflavones genistein and
daidzein have cancer-protective properties, particularly against
hormonally sensitive cancers, such as prostate cancer in men and breast
cancer in women. The typical Japanese diet is also low in meat and high
in seafood. Fish contains significant concentrations of the important
cancer-fighting fatty acids EPA and DHA. Another cancer preventive
typically consumed at almost every Japanese meal is green tea, which
contains a powerful anticancer agent known as EGCG
(epigallocatechin-3-gailate). Drinking several cups of green tea every
day is highly recommended.
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