Healthy Living October Issue
GOOD NEWS ABOUT CANCER: IT CAN BE PREVENTED!
How Cells Become Cancerous
Let us look at what cancer actually is. Cancer involves the production
of cells in the body. Every minute 10 million cells divide in our bodies.
Complex internal control mechanisms usually ensure that every one of
these cell divisions occurs in a precise way at just the right time.(10)
The process called cancer can begin when foreign substances in the
external environment (chemicals, radiation, viruses, etc.) get into the
body and somehow perturb these internal control mechanisms. It can also
begin as a result of problems that originate with the body¡¯s internal
environment (hormonal imbalances, immune impairment, inherited mutations,
etc.).11 Regardless of the combination of factors that start the process,
the result is the same: a single cell begins to multiply in an
unregulated manner. As this cell multiplies, it passes its characteristic
of unregulated growth to its offspring. A cancerous tissue made up of
many unregulated cells is the result.
One of the ways that environmental agents appear to induce cancer is by
inflicting damage on the cells¡¯ DNA. DNA contains explicit instructions
for all cell activities and thus spells out exactly how each cell in our
body should function. For example, the DNA tells our bodies what color to
make our hair and whether we should have blue eyes or brown eyes. This
same DNA controls the rate of division of cells. On certain critical
areas of a cell¡¯s DNA there are genes that can stimulate the growth of
that cell and other genes that can suppress its growth. One way that
cancer can occur is through damage to this DNA. If the damage causes
activation of areas that stimulate growth and/or the inactivation of
areas that would keep growth in check, the result can be uncontrolled
growth of that cell and its offspring. This, as we have noted, signals
the beginning of a cancerous growth.12 We refer to that altered cell as a
cancer cell if its genetics are changed in such a way as to allow
uncontrolled multiplication.
If the body detects abnormal cancerous cells at an early stage, those
cells can be destroyed before they have a chance to significantly grow
and multiply. In fact, many scientists believe that every day-in every
person-some normal cells are converted into cancerous cells. Usually,
the person¡¯s immune system destroys these newly altered cells.
Unfortunately, however, sometimes a new cancerous cell is not detected
and it manages to divide and grow without check. These cells can then
continue to silently grow out of control. Ultimately they can form a
mass or ¡°tumor.¡± Commonly, cancer cells from larger tumors will get into
the blood stream and/or lymph system and travel to other vital organs.
All of these changes may occur long before the cancer is even diagnosed.
Depending on the growth rate of the cancer, it may take 10 years or
longer before signs or symptoms develop that ultimately prompt the medical
evaluation that results in the diagnosis of cancer.13
In this chapter you will learn how to detect if you have cancer, and also
how to reduce your risk of getting it. We begin by presenting means of
detecting cancer.
Early Detection is Crucial
Early detection provides the best chance of treating cancer while it is
still curable. There are two ways to do this: (1) prompt recognition of
cancer¡¯s symptoms and (2) appropriate use of cancer screening tests.
Recognizing Cancer's Symptoms
Cancer is often curable if detected early enough. Unfortunately, many
patients are not mindful of the importance of early detection. Time and
time again I have been forcibly impressed with this sad reality. In
addition to my work in general internal medicine, I work in the field
of gastroenterology. I have many patients who come to my office
complaining of intermittent bleeding from the rectum for perhaps a year
or more before seeing me or any other physician. Some put off that
doctor¡¯s visit because of simple procrastination, while others may have
delayed because of the fear of cancer. Still others may have dismissed
the seriousness of this warning sign, thinking it was due to a minor
condition like a hemorrhoid. Only after they start having pain or other
symptoms do they finally decide to have me evaluate the bleeding problem.
By this time, for many, it is already too late.
In my evaluation I use a colonoscope-a long, flexible tube that is
inserted into the rectum and passed up through the large intestine,
or colon. It has a light at the end that allows me to directly look
at the inside of the intestine. It also comes with special tools for
removing early cancers or non-cancerous polyps without major surgery.
As I look through the scope I occasionally find a cancerous mass that
is already too large for me to remove. At that point there may be
little chance of cure, but the person may still need major surgery-at
least to avoid a total bowel blockage. Frequently, death is the
result, since by this time the cancer has often spread to vital organs
such as the liver.
The message that this and a thousand other scenarios illustrate is that
everyone should pay attention to cancer¡¯s warning signs. It is only by
heeding these early warnings that we have the best chance of detecting
and treating the disease while it is still curable. For years, the
American Cancer Society has encouraged all Americans to be aware of
seven of the most important cancer warning signs. These are listed in
Figure 2: Seven Warning Signals of Cancer.14
Most of these warning signs are self-explanatory. For example, ¡°a
change in bowel habits¡± can refer to persistent diarrhea or
constipation as well as to changes in color or size of the stools.
¡°Bleeding¡± includes such things as rectal or unusual vaginal bleeding.
¡°Difficulty in swallowing¡± can occur when food seems to remain in
your esophagus (swallowing tube) before it goes down. The important
message is that any of these seven signs indicates a need for a prompt
medical evaluation. Paying attention to your body and recognizing
when you develop something that needs to be evaluated may provide a
window of opportunity where cancer can be diagnosed-and cured-in its
early stages. Unfortunately, even prompt evaluation of these signs
does not guarantee that we will diagnose a cancer at a treatable stage.
Recently I had a patient that came to me after only a single episode
of rectal bleeding. When I checked the stool microscopically, blood
was present. A few days later I did a colonoscopy exam and found a
tumor so large that I could not remove it using the scope. Other lab
tests showed that the cancer had already spread to the vital organs.
Yet for every patient like this, I have others who initiated prompt
evaluation of rectal bleeding and turned out not to have cancer-or
to have it at an earlier stage so that it could be safely removed by
using the colonoscope.
Yes, prompt evaluation of any of cancer¡¯s warning signs is important
and should never be put off for a convenient time. It can save your
life. However, there is an even better alternative: take advantage
of any opportunity to detect cancer before any signs or symptoms
develop.
Two Primary Lines of Defense Against Cancer
There are two basic strategies that will prevent most cancers from
starting; even if cancer has already begun, they may help the body
gain an upper hand. These strategies are simple:
- Avoid factors that favor cancer development.
- Take advantage of factors that help the body to ward off cancer.
These two strategies are usually effective because of one or both of
the following reasons:
- They help us avoid or minimize contact with cancer-causing substances.
- They help us strengthen our body¡¯s own immune system for fighting cancer.
The remainder of this chapter is divided into two sections. The first
section deals with minimizing contact with cancer-causing substances.
The second deals with the agents that will help our immune system to
fight cancer, and other agents that will reduce our risk of getting
cancer.
CANCER PREVENTION
Agents That Act to Reduce the Risk of Cancer
In many of my original presentations on cancer, I entitled this section
¡°Increase Factors To Boost Your Immune System.¡± However, extensive
research on the subject of cancer revealed that lifestyle factors that
protect us from cancer involve more than their important effects on the
immune system. There is a variety of ways that healthful choices help us
ward off cancer. Even though this chapter takes a broad approach to
cancer preventive factors, I still marvel at how many of these factors
exert their protective influence by strengthening our immune systems.
Our bodies are continuously under attack from a variety of germs, toxins,
and pollutants. We breathe air that contains dirt particles, smoke,
fumes, carbon monoxide, and chemicals. We handle garbage in the normal
process of life. We eat food full of bacteria and drink water with
varying degrees of contamination from a host of wells and municipal water
systems. Night and day, day after day, we encounter countless
microbiologic enemies who want to dominate us for their own purposes.
Simply put, there is no way to go through life completely avoiding all
threats to our health. And there is no way to avoid each and every
carcinogen. No matter how hard we try, we will on occasion breathe in the
toxins from someone else¡¯s cigarette smoke, or factory, or incinerator.
Because these dangers are all around us, many people throw up their
hands and say, ¡°Forget it. I will never be able to avoid every
carcinogen, so why even try?¡± This defeatist attitude ignores two
important facts. First, it is not an all-or-none phenomenon regarding
the dangers of carcinogens. Exposure to a few carcinogens is not as
harmful as exposure to many carcinogens. The more we avoid carcinogens,
the greater the protection we will enjoy. Second, the ¡°why try¡±
argument ignores the fact that our immune systems can help us deal
effectively with carcinogens. When we are exposed to a moderate level
of carcinogens and our immune systems are in tip-top shape, we can
destroy cancer cells before they have a chance to multiply to any
significant extent-and before they have a chance to cause symptoms or
even be detected on an x-ray or a blood test. This is, indeed, good
news concerning the immune system.
The immune system has one mission: to identify and destroy foreign
invaders before significant harm is done to our bodies. Disease-causing
organisms such as bacteria, viruses, fungi, and parasites, are detected
upon entry by a healthy immune system, and are tagged for elimination by
hungry immune system cells. Cancer cells should be similarly detected
as abnormal cells, treated as unwelcome intruders, and eliminated with
a strong immune system.
Our singular duty to the immune system is to develop a lifestyle that
will support its constant defense work on our behalf. How we live day
by day determines whether our immune system works at peak levels or is
inhibited by our neglect and even abuse. But is it possible to strengthen
our immune system? Yes, there are a variety of ways we can provide help
to our immune systems. Three of the most important are diet, exercise,
and stress control. Let us first look at diet, both from the perspective
of its immune-enhancing potential and its ability to help us deal with
cancerous threats on other levels.
Vitamin A and Related Compounds
It is widely known that vitamin A is required for the maintenance
of normal mucous membranes and for normal vision.177 However, few
realize that, as one nutrition text put it, ¡°Vitamin A is essential,
either directly or indirectly, for the proper functioning of most
organs of the body.¡±178 Indeed, vitamin A is important for reproductive
function in both males and females, and it also appears to be critical
for immune function.
Vitamin A is present in the diet as the fully active form of the
vitamin (called the preformed vitamin) and as precursor compounds that
the body can convert into vitamin A. The most familiar precursor is
beta-carotene. Animal products can be rich sources of preformed vitamin
A, but toxicity can also occur from too much of the vitamin in this
active state. Beta-carotene, a plant substance, is safer: when vitamin
A activity is needed, the body can readily convert it into the active
vitamin. Unlike vitamin A itself, beta-carotene is virtually never
toxic regardless of the level of intake even if it makes your skin yellow.
Animal products rich in preformed vitamin A often have other strikes
against them. Some of the richest sources, like liver, whole eggs, and
whole milk are also best avoided because they are loaded with cholesterol.
Both human epidemiology and animal research suggest that vitamin A is
important for reducing our risk of cancer. One classic Norwegian study,
published in 1975, reported five years of research on over 8000 men.
Dr. Bjelke found that, for any given level of smoking, low vitamin A
intake increased lung cancer risk.179 For the total population, which
includes smokers and nonsmokers, those who had low levels of vitamin A
intake had over double the risk of lung cancer. More impressively, those
who ever smoked had over four times the risk of developing the most
common smoking-related lung cancers if their vitamin A intake was low.
A more recent Japanese study also found that low blood levels of vitamin
A increased the risk of lung cancer. Those with serum vitamin A levels
in the lowest third had nearly six-times the risk of lung cancer as those
with levels in the upper third.180 Not all lung cancers are developed
in smokers. Up to 15 percent of lung cancers can occur in those who do not
actively smoke, but may be exposed to varying levels of second-hand smoke.
Those nonsmokers with a higher beta carotene intake from fruits and
vegetables had only 70 percent of the risk of lung cancer as those eating
less beta-carotene.181
A host of other beta-carotene relatives occurs in plants. These are
called carotenoids and can also be converted into vitamin A.182 Some of
these carotenoids include beta cryptoxanthin, lutein, and lycopene.
Lycopene causes the red color in strawberries and tomatoes. Foods that
are particularly rich in lycopene have been associated with prostate
cancer prevention. Harvard¡¯s Health Professionals Follow-up Study found
that men who ate tomato sauce as little as once per week had prostate
cancer risks 23 percent lower than those who never ate it.183 Those men
eating tomato-based products ten or more times per week were up to 35
percent less likely to develop prostate cancer. The study¡¯s lead author,
Dr. Edward Giovan-nucci, believes that lycopene may be the key ingredient
that causes this risk reduction.
Those with the lowest lycopene blood levels also have a significantly
increased risk of developing pancreatic cancer.184 Lycopene, like most
of the helpful beta carotene relatives, cannot be found in pills but
only in fruits and vegetables.
To what do the vitamin A-related compounds owe their protective
qualities? First, they act as antioxidants.185 In this role, they help
the body dispose of chemicals called free radicals that can genetically
damage normal cells and set the stage for cancer. (Free radicals are
explained in the next section). Second, vitamin A-related compounds
appear to be capable of stimulating the immune system. Mice given
additional vitamin A have an improvement in the function of their T
lymphocytes, which are a variety of white blood cells that destroy
cancer cells.186 Third, vitamin A compounds help body tissues to
differentiate, that is, develop in a normal, orderly fashion. Since
cancer is characterized by a lack of differentiation, some theorize
that vitamin A may help to reverse early cancerous changes by helping
those abnormal tissues to move into a more orderly state of growth.187
Free Radicals and Antioxidants
I have made mention of free radicals already in this chapter; they are
explained more fully in connection with the antioxidant capacities of
melatonin in Chapter 9, ¡°Melatonin: Agent for Rest and Rejuvenation.
¡± However, in order to understand the importance of antioxidant action
in preventing lung cancer, some comments about free radicals are in order.
Normally every molecule has electrons that are in orbit around its
nucleus. Those electrons normally come in pairs, and render the
molecule chemically stable. However, a free radical is a molecule that
has an unpaired electron. This leaves it extremely unstable. It has a
powerful drive to acquire an electron to pair with the one that lacks
a partner. Often within a fraction of a second, a free radical will
grab an electron from a neighboring compound. That neighbor who lost an
electron is said to have been ¡°oxidized.¡± Furthermore, the oxidized
compound itself typically becomes a free radical. Since it now is
missing an electron, it has a strong desire to grab one from one of
its neighbors-and it usually does so in short order. The result is a
chain reaction, where oxidation and damage can spread from one
molecule to the next until something stops the process. Molecules
that can stop this chain reaction are called antioxidants, which restore
the unstable molecules to a chemically stable condition.
Free radicals have been observed to damage DNA and have been linked
to cancer. One fascinating series of experiments that linked free
radicals to cancer focused on a gene called K-ras. If the normal
human K-ras gene is damaged, it can actually cause cancer. Twenty to
forty percent of all cancers of the colon, pancreas, and lung appear
to be caused at least in part by changes in this gene. There are a
few specific locations on the K-ras gene that must be damaged before
it takes on this cancer-causing role. The ¡°addresses¡± for these gene
locations are technically referred to as codons numbered 12, 13, and
61. Dr. Jackson and associates at the Scripps Research Clinic in
California found that free radicals from cigarette smoke and other
sources can damage K-ras specifically at two of these critical codons
(numbers 12 and 61). This damage is more technically called a
mutation. The message is that cancer-causing substances such as
cigarette smoke may perform some of their dirty work by acting as
free radicals.
While on the subject of free radicals, I should point out that
radiation is yet another well known cause of free radicals.188 This
kind of free radical production may provide much of the explanation
for the increased cancer risk in atom bomb survivors. There are
things we can do to limit our exposure to free radicals. However,
because all living creatures produce them, we cannot completely avoid
these highly reactive compounds. It is for this reason that I
encourage individuals to strengthen their antioxidant defenses in
addition to avoiding free radicals.
Where can we find foods that are rich in the antioxidant capacity
provided by Vitamin A-related compounds? The quantities of vitamin
A (as beta-carotene) in certain foods are listed in Figure 19: High
Level Carotene (Vitamin A) Foods.189
Note that root vegetables are specifically high in beta-carotene.
There is a whole host of other Vitamin A relatives (retinoids) in
plant foods that are not included in this list.
Since high beta-carotene intake has been associated with low rates of
certain cancers, many have concluded that they can protect themselves
from these cancers by taking vitamin A or beta carotene supplements.
So far, medical research suggests that these supplements do not provide
the benefits that eating plant foods rich in beta carotene delivers.
190 However, for those not taking supplements, the higher the blood
levels of beta-carotene, the less the risk of both cancer and heart
disease.191
A Finnish study of nearly 30,000 male smokers found that taking
beta-carotene pills for up to eight years actually increased their
risk of lung cancer by 18 percent.192 Beta-carotene, like many
antioxidants, can actually become a free radical or paradoxically
increase free radical production when consumed in large amounts by
itself.193 However, when beta carotene is combined with adequate
Vitamin C, Vitamin E, and other antioxidants such as is found in
beta carotene natural foods, a potent antioxidant effect occurs.194
Some are wondering if beta-carotene may be more important in the
bloodstream as an indicator of a plant-rich diet that has many other
anticancer factors going for it. We will look at a number of those
compounds later in the chapter.
There is another danger of beta-carotene supplements. In both human
and animal studies, taking beta-carotene pills can lead to the
depletion of vitamin E in the body. Mice as well as humans have shown
40 percent drops in their vitamin E levels while on beta-carotene
pills.195 This is just one example of what are referred to as
¡°vitamin-vitamin interactions.¡± There are dozens of such interactions,
where taking one vitamin increases or decreases your requirement
for another. The safest policy is to eat a variety of plant foods
that are loaded with a balanced supply of vitamins as well as other
cancer-protective substances-some of which have not yet been
iscovered.
Eat Foods Rich in Vitamin C
Vitamin C is another cancer-protective food. Its main effects are
also likely due to its role as an antioxidant, similar to vitamin A,
thus decreasing exposure to toxic ¡°free radicals.¡±
Vitamin C also tends to prevent the formation of carcinogenic
nitrosamines from nitrites in the diet.
It does more than protect the person himself from cancer. Recent
research suggests that vitamin C may help to protect sperm from
genetic damage. There is evidence that genetically damaged sperm
may cause inherited diseases such as cancer in the next generation.
Vitamin C provides protection through its role as an antioxidant.
Certain childhood malignancies such as leukemia and cancer of the
kidney and brain have their roots in the father¡¯s genetically
damaged sperm.196 Such sperm abnormalities may represent a combination
of factors such as cigarette smoking197 (which appears able to
actually oxidize the sperm and genetically damage it), a poor diet
(less than 250 mg of Vitamin C a day)198 and low consumption of
other antioxidants), and exposure to occupational toxins. Thus a man¡¯s
lifestyle, including eating habits, from a few weeks prior to
conception up to the time of conception is vitally important in
determining the integrity of his offspring¡¯s DNA.
The recommended dietary intake for vitamin C as published by the
National Academy of Sciences is 60 mg per day. However, I believe
every American should consume at least 250 mg daily. My reasoning
is not only for the benefits to men in protecting their sperm for
future generations, but also because of the important role that
vitamin C plays as an antioxidant. Furthermore, since vitamin C is
abundantly supplied in our foods, obtaining this level of intake
is not difficult. Some good sources of this important vitamin are
listed in Figure 20: Foods Rich in Vitamin C.199
Eat Foods Rich in Vitamin E
Vitamin E appears to help protect against cancer for similar reasons
that vitamin C does. It is an antioxidant and a free-radical
scavenger. It also has a role in blocking the formation of
carcinogenic nitrosamines and nitrosamides from foods containing
nitrite.200,201,202
As an example of the power of antioxidant vitamins to reduce cancer
risk, consider the following study. Researchers obtained a hairless
strain of rabbits that were prone to skin cancer and exposed them to
ultraviolet light to accelerate the development of cancer. The
results are shown in Figure 21: Diet can Protect Against Skin Cancer.
Vitamins C and E provided complete protection against skin cancer. The
antioxidant action of these vitamins apparently decreased oxidization
of the tissues where skin cancer tends to develop.203
The rabbit skin cancer tests are in agreement with a recent human
study of lung cancer from Japan. In this study, it was found that
those with low blood levels of vitamin A (beta-carotene) had a
six-fold greater risk of lung cancer compared to those with higher
levels. The same study found an even more impressive protective
effect for Vitamin E blood levels. Those with levels in the lowest
third had nearly 8.5 times the risk of those with levels in the
upper third.204
It is important to emphasize that most studies that have looked at
cancer protection from antioxidants like vitamins A, C, and E,
have involved individuals who were generally getting their vitamins
from natural foods, not vitamins in a bottle. Many people are under
the impression that vitamin A, C, and E supplements will provide
adequate strength to their immune system. However, as we have seen,
some of the research indicates that vitamin supplements do not
furnish the protection that food sources of these vitamins provide.
Furthermore, foods containing these vitamins (fruits and vegetables)
contain a host of naturally occurring protective substances in
addition to these widely-hyped vitamins.
If you are looking for some good natural sources of vitamin E, a
list of foods that provide healthy doses of this antioxidant vitamin
is shown in Figure 22: High Sources of Vitamin E.205
One additional consideration is in order: as beneficial as
antioxidants like vitamins A, C, and E are, antioxidants are not all
good. Excessive amounts can paradoxically act as ¡°pro-oxidants,¡±
compounds which actually favor the formation of free radicals. This
is true of vitamin C and vitamin E as well as other antioxidants
such as superoxide dismutase and glutathione.206 However, when beta
carotene, Vitamin C, and Vitamin E are present in abundant-but not
superabundant-amounts (i.e., in whole plant foods) they actually
work in combination to elicit a protective antioxidant effect. This
effect is much more powerful than just the additive effects of these
three separate antioxidants.207 Furthermore, supplements consist
almost entirely of one particular type of vitamin E, called
alpha-tocopherol. A recent study has found that another type of
vitamin E, gamma-tocopherol, may be a better antioxidant and thus
better at inhibiting DNA-damaging particles in the body.208 About
75 percent of vitamin E consumed from food is in the gamma-tocopherol
form, while supplements contain either none, or less than 10 percent
gamma-tocopherol. The most effective action is to temper your
enthusiasm for patronizing your local vitamin supplier, and instead
invest in more fresh fruits and vegetables.
Whole Plant Foods Alone--Powerful Antioxidants
Another illustration of the power of plant foods to assist in cancer
prevention and possibly even to combat the effects of aging was
provided by the United States Department of Agriculture (USDA).
They recently attempted to rate foods according to their measured
natural antioxidant properties. Although they used only one group
of free radicals (the peroxyls) in their testing, the University of
California at Berkeley championed the research on the headlines of
their March 1997 newsletter. This research is the first that I am
aware of that rated the power of whole plant foods (as opposed to
just the sum of their vitamin A, C, and E content) to provide
antioxidant effects. The top ten fruit and vegetable sources of
antioxidants from this USDA research are listed in Figure 23: The
Antioxident Top Ten Fruits and Vegetables.209,210
Each of these foods has much more antioxidant activity than the sum
of the antioxidant content of vitamins A, C, and E. For example,
one cup of cooked kale has as much antioxidant activity as about
800 mg of Vitamin C or 1100 IU of Vitamin E. However, the kale only
contains about 50 mg of Vitamin C and 13 IU of Vitamin E. What
accounts for the difference? A whole host of other antioxidants in
the kale that we often do not measure. It is well established that
many fruits and vegetables have powerful antioxidant effects far
beyond what an assessment of conventional vitamin contents would
reveal.
These rankings should be viewed with the realization that only a few
dozen foods were analyzed, with some food groups not being
represented at all-such as the legumes.
Phytochemicals
The natural chemicals that are found in plant foods are called
phytochemicals. In one sense of the word, vitamins or any other
constituent that is found in a plant product could be given this
designation. However, the term is most often used for food chemicals
that come from vegetarian sources that cannot be obtained from animal
products. There are literally thousands of phytochemicals, many of
which appear to have a role in fighting cancer. Many of these
chemicals have just recently begun to be appreciated. No doubt many
other phytochemicals are yet to be discovered.
Even so, whatever you find in a food supplement pill represents
yesterday¡¯s science. Regardless of what becomes next year¡¯s hottest
selling phytochemical in the health food store, you can be reasonably
certain that those who eat an abundance of plant foods have already
been getting generous doses of that compound. On the other hand, those
who skimp on fruits and vegetables will be obliged to wait for the
vitamin companies to first be convinced of the compound¡¯s promise and
salability, and then figure out how to get it into a pill.
Study after study continues to reveal the cancer-protective benefits
of different phytochemicals. Dr. John D. Potter of Seattle¡¯s Fred
Hutchinson Cancer Research Center has pointed out that these
phyto-chemicals usually work in one of two ways: they either function
as blocking agents or suppressing agents.211 Blocking agents work on
the carcinogens-preventing them from affecting the body¡¯s cells (this
may occur by destroying their activity or other means). Suppressing
agents work on the body¡¯s own cells, combating malignant changes that
may have been started by carcinogens.
Many of the insights on the health benefits of phytochemicals come
directly from the laboratory. A list of a few of the phytochemicals
that have been shown to prevent or even treat cancer in the laboratory
and the foods they are found in are listed in Figure 24: Food Sources
of Cancer- Fighting Phytochemicals.212,213,214,215,216
Most of the research on the effects of phytochemicals on humans comes
from nutritional epidemiologists. These researchers study the dietary
habits of people and then draw conclusions as to which dietary factors
are protective and which are harmful. Most of us do not sit down to a
meal of supplement pills that consist of isolated phytochemicals.
We obtain these protective compounds in the fruits, grains, nuts, and
vegetables that we eat. As a result, research tends to show connections
between foods that are rich in phytochemicals and cancer risk.
Identifying which specific phytochemicals are providing the benefits is
usually open to question. Even though statistical models may tend to
single out one or a few compounds, there are likely many hundreds of
compounds that we do not know about-many of which may be even more
potent that those that we already recognize. From this perspective,
let's take a look at a few examples from the medical literature to more
fully appreciate how phytochemical-laden foods appear to be decreasing
cancer risk.
One group of foods that are loaded with cancer-protective factors are
the cruciferous vegetables. These members of the cabbage family include
brussels sprouts, cauliflower, broccoli, kale, turnips, kohlrabi, bok
choy, collards, and cabbage. One study showed that those who ate cabbage
at least once per week had two-thirds less colon cancer than those who
ate it once per month or less.217 Indoles are among the cancer-protective
phytochemicals in these plants. These compounds work as blocking agents
by increasing colon enzymes that can deactivate carcinogens.218
Eating whole fruit dramatically reduces the risk of certain cancers.
In the Adventist Health Study involving 34,000 subjects, Seventh-day
Adventists that eat fruit twice a day decrease their risk of developing
lung cancer by a startling 74 percent compared to those that eat fruit
less than twice a week. Stomach and other cancers were also dramatically
reduced.219
Over 90 percent of the 34,000 subjects were nonsmokers, which meant
that they were all at a low risk of developing lung cancer at the outset.
However, nonsmokers infrequently do get lung cancer. This study shows
that their risk can be sharply lowered even more by including an
abundance of fruit in their diets.
Soy is another food highly touted for its cancer-protective properties.
It is a veritable gold mine of cancer-protective phyto-chemicals. Dr.
Mark Messina summarized over 30 different epidemiologic studies on
soybeans and cancer in his book, The Simple Soybean And Your Health.220
He points out that the results suggest that those who consume the most
soy foods have the least cancer. These studies suggest that soy
decreases cancer risk at many sites including breast, colon, rectum,
lung, and stomach.
A large study from the Netherlands involved over 120,000 men and
women. Researchers there made a connection between another
phytochemical-rich food and cancer prevention, the simple onion. The
cancer it prevented was stomach cancer. Those eating the most
onions (one or more onions every other day) had half the stomach
cancer risk of those who never ate onions.221
Garlic has been shown to protect against developing cancer; in mice,
it is effective in treating cancer. The amount of 50 milligrams of
garlic administered in 3 ounces of drinking water to mice with
bladder cancer led to significant shrinking of the tumors, while 500
milligrams of garlic not only reduced the cancer size but actually
decreased the mortality rate from the cancer.222 All of this occurred
without side effects. The researchers believe that the garlic may
have stimulated the mice¡¯s immune systems, helping them to combat
the cancer.
The message from these few selected examples is not that we should eat
a soy, cabbage, and onion sandwich every day. Rather, I recite these
studies only to illustrate the wealth of scientific information that
is coming out about many fruits, grains, and vegetables. In fact,
some of the most exciting research looks at all these foods
collectively. For example, Harvard¡¯s Dr. Walter Willett has observed
that there is abundant and consistent scientific evidence which
demonstrates that ¡°high intakes of fruits and vegetables¡± reduce the
risks of ¡°most human cancers.¡±223 Willett sees in this evidence
support for ¡°the concept that micronutrients [such as vitamins,
minerals, and other phytochemicals] may play important roles in the
prevention of human cancers.¡±224 Indeed, the consumption of fruits
and vegetables is associated with lower rates of cancers of the breast,
colon, rectum, lung, prostate, urinary bladder, stomach, esophagus,
cervix, larynx (voice box), mouth, pharynx (throat), and liver.225,
226, 227
The National Research Council has come to similar conclusions as Dr.
Willett: ¡°There is consistent evidence that fruit and vegetable
consumption is protective against several cancers... Therefore, in
considering appropriate preventive measures, consumption of the
relevant foods (the foods themselves)-not the putative protective
components of those foods-should be encouraged.¡±228 In other words,
the Council is encouraging all Americans to eat foods that contain
cancer-protective compounds rather than seeking supplements that
feature those compounds. Considering the overwhelming evidence as
to the importance of protective phytochemicals in fruits, grains,
and vegetables, I could not agree more.
Even if the prospects of making a dramatic dietary change seem
daunting, take heart. There are many natural food cookbooks that can
make the transition much easier. These books feature an abundance
of fruits, grains, and vegetables in a multitude of good tasting
recipes. Appendix II lists several such books.
Fiber Reduces Cancer Risk
Another nutrient class that some would include among the
phytochemicals is that of fiber. Fiber includes the parts of plant
materials that resist digestion by the normal human intestinal system.
Just as there are many different types of vitamins, so there are many
different types of fiber. These include celluloses, hemicelluloses,
lignin, pectins, gums, mucilages, and algal polysaccharides. Major
food sources of fiber are fruits, vegetables, whole grain cereals,
and legumes.229 There is virtually no fiber in meat, milk, eggs,
cheese, or any other animal product.
A fiber-rich diet clearly reduces the risk of developing colon cancer.
Drs. Howe, Benito, and colleagues analyzed the results of 13 studies
that looked at the influence of fiber intake on colon cancer.230 They
found a strong dose-response relationship when they looked at fiber
intake: the more fiber eaten, the lower the risk of colon cancer.
Specifically, when the researchers divided people into five groups
based on their level of fiber intake, those with the lowest fiber
intakes had the greatest risk of colon cancer. Even those in the next
lowest group of fiber consumption still had 21 percent less colon
cancer when compared to the poorest fiber eaters. Those in the group
with average fiber intake had 31 percent less, those with somewhat
above average intake had 37 percent less, and those with the best
fiber intake had nearly 50 percent less risk of this major cancer.
The researchers concluded that if the average U.S. citizen would merely
increase his or her fiber intake by 70 percent (thus going from a
current average of about 18 grams per day to around 30 grams per day),
we would decrease our national rate of colon cancer by 31 percent and
would save some 50,000 cases of colon cancer annually.231
Earlier in this chapter we looked at data from Harvard University¡¯s
Health Professionals Follow-Up Study. Researchers there studied the
relationships of lifestyle to the lesions that precede colon cancer,
known as colorectal adenomas. In addition to finding links with alcohol,
the Harvard group has documented relationships between these adenomas
and both high saturated fat consumption and low fiber intake.
Specifically, those with high saturated fat intake had double the risk
of these lesions. Men with the poorest fiber intake had almost three
times the risk of colorectal adenomas when compared with those consuming
fiber liberally. When they identified a group of men eating liberal
amounts of saturated fat and little fiber, they discovered that they
experienced nearly four times the risk of those on a low saturated fat,
high fiber diet.232
Why does fiber lower cancer risk? There is a variety of possible
reasons. These include:
- Fiber draws water to itself. Therefore, it may help to dilute any
carcinogens that gain access into the intestine.
- Fiber helps to speed up the passage of colon contents, thus
decreasing the time for any potential carcinogens in the stool to
damage the lining of the colon.
- Fiber helps to decrease the production of altered bile acids known
as ¡°secondary bile acids.¡± These altered bile acids appear able to
cause colon cancer.
Dietary fiber has protective benefits regarding other cancers as well.
For example, a high fiber diet has been shown to decrease breast
cancer by more than 50 percent.233 Dr. David Rose of the American
Health Foundation believes that the evidence suggests that fiber ¡°may
favorably modify the enhanced breast cancer risk associated with the
typical American high-fat, low-fiber diet.¡± He suggests that fiber may
work through a variety of ways to lower breast cancer risk, but the
primary effect is probably through affecting either the activity or
the metabolism of estrogen. Associated with plant fibers are plant
estrogens (¡°fiber-associated phytoestrogens¡°) that may lower breast
cancer risk. There is also evidence that fiber can interfere with
the intestinal re-absorption of estrogen-this would also be expected
to lower breast cancer risk.234
Selenium
Selenium is a trace mineral found in whole grains, such as wheat
grown in North and South Dakota in selenium-rich soil. A diet high
in selenium (approximately 200 to 400 micrograms a day) decreases
the risk of lung, colon, and prostate cancer.235 But another word of
caution for supplement users: too much selenium is toxic and causes
hair and nail loss, bad breath, or other symptoms.
Maintain Proper Weight
Increased body weight has been linked to an increased risk of several
different types of cancer. The list includes cancers of the breast,
kidney, endometrium (inner lining of the womb), and prostate.236 Let us
examine a few of the many studies that have explored this relationship.
A classic Japanese study done by Dr. Hirayama found that thin women had
the lowest rates of breast cancer, as portrayed in Figure 25: Obesity
Increases Breast Cancer Risk. 237
In this figure, the ¡°overweight¡± category was up to about 20 percent more
than the upper limit of normal weight; obese was any weight above the
¡°overweight¡± range. Note that obese women had a three-fold increased
risk for those who had not yet gone through menopause, but the risk
climbed to a twelve-fold level for those who were post-menopausal.
Another way to look at factors that predispose women to breast cancer is
to study those who developed more than one breast cancer that was not
spread from the initial cancer. Such studies are important because they
would be expected to identify a group of women who have special factors
favoring the development of breast cancer. In 1985, other Japanese
researchers identified such a group of over 60 patients and compared
them with individuals who had just a single breast cancer.238 A strong
relationship emerged between weight and multiple breast cancers. Those
who were overweight had triple the risk of having more than one episode
of breast cancer, demonstrating that the overweight condition in some
way predisposed them to the development of this malignancy.
American research has also been published on the breast cancer-overweight
relationship. Dr. Kumar and associates at the University of
South Florida found that weight gain from puberty to early adulthood was
especially important in increasing breast cancer risk. They found that an
extra 10 pounds on a 30-year-old woman raised her risk of breast cancer
by 23 percent, while an extra 20 pounds raised her risk 52 percent.239
Gaining weight after the age of 18 has just recently been found to be
an ¡°independent risk factor¡± (apart from alcohol consumption, use of
hormones, physical activity levels, age of first pregnancy, menarche,
and menopause) for the development of breast cancer.240
Women are not the only ones who experience an increased cancer risk
due to being overweight. In 1985, Dr. Garfinkel reported results from
one of the largest studies that examined the relationship between body
weight and cancer risk of 750,000 men and women. A 12 year follow-up
study revealed increased cancer mortality for those who were overweight.
The findings are tabulated in Figure 26: Obesity aned Increased Risk of
Death from Cancer.241
Note that men who were 40 percent overweight had a 33 percent increased
risk of dying from cancer. Women who were overweight by the same
percentage increased their cancer death rates by 55 percent. In men,
this relationship was statistically significant for cancers of the colon,
rectum, and prostate. For women, risk increased not only for breast
cancer but also cancer of the uterus (cervix and endometrium), ovary,
and gallbladder.242
Why would being overweight increase cancer risk? There are several
possible explanations. First, excess fat stores may influence
hormonal levels. Being overweight increases the risk of something
called insulin resistance which in turn leads the pancreas to make
more insulin in order to control blood sugars. This may in turn increase
colon cancer risk. There is evidence that insulin is an important
growth factor for colon cancer cells. Hormonal effects also enter
the picture with breast, ovarian, and uterine cancers. Fat tissue can
convert a hormone made by the adrenal gland (called androstenedione)
into estrogen. This excess estrogen can further stimulate cell growth
in hormone-sensitive female tissues, thus increasing the possibility
of cancerous changes over time.
Second, excess fat stores may serve as a repository for fat-soluble
toxins. More body fat allows for greater storage of these compounds
that can later be mobilized and transported to tissues that are
sensitive to the cancer-inducing effects of these toxins.
Third, having more body fat stores provides more readily available
energy resources. This in turn may stimulate cell multiplication
and thus affect the promotion phase of cancer development. Excess
weight carried around the stomach may be more of a risk in this
regard than excess weight on the hips. Fat in the stomach area seems
to be much more metabolically active.
Fourth, being overweight may identify a population that, in
general, eats more calories. This is of significance to cancer.
It has been known for years that caloric restriction tends to
protect from cancer while excess caloric intake appears to increase
cancer risk. Total per capita calories consumed have been linked in
international comparisons with cancers of the breast, colon, rectum,
uterus, and kidney.
Fifth, being overweight may be indicate higher fat consumption.
Laboratory animals tend to become overweight if given foods that are
highly palatable to them, particularly foods that are high in fat
and low in fiber. Similar relationships have been found in research
on humans. We have already noted how a higher fat diet increases
cancer risk. It disturbs hormonal balance and may independently
suppress immune system function.
How do you know if you are overweight? There are a variety of ways
to find out: one of the standard methods is to compare yourself to
tables such as those published by the Metropolitan Life Insurance
Company. However, those tables do not work well for people that
have significantly greater amounts of muscle mass than average.
By such standards most body builders, for example, would be
overweight. Therefore, some feel a more important determinant is
whether you are ¡°over-fat.¡± Measurements of body fat can be made
by a variety of methods ranging from underwater weighing to skin
fold measurements. Newer methods use an infrared beam or resistance
to a weak electrical current to estimate body fat percentage.
A simpler and yet very valuable method for estimating excess body
fat compares the size of the waist to that of the hips.243 You can
do this yourself. Take a measuring tape and measure around your
hips, then around your waist. For women, the waist size should be 20
percent less than the hip size. For example, if the hips measure
40 inches, the waist should be 8 inches less, or 32 inches (0.2
times 40 = 8). If it is any larger than 32, you have excessive weight.
For men, the waist size should be 10 percent less than hip size.
For example, if the hips measure 40 inches, the waist should be 4
inches less (40 times 0.1 = 4), or 36 inches.244 If it is larger,
you are overweight. Those who are over-fat by the waist/hip method
not only have a greater risk of cancer but also a greater risk of
diabetes, hypertension, and coronary heart disease.
Watch Out for Excess Protein
A diet low in protein, particularly in certain amino acids, will
also strengthen the immune system against cancer. More information
is provided in Chapter 7 entitled, ¡°The Great Meat and Protein Myth.¡±
Viruses in Animal Products
A partial listing of viruses known to cause human cancers includes:
the Hepatitis B virus, the Epstein-Barr virus, human T-cell leukemia
viruses, and HIV, the human immunodeficiency virus.245 The human
papilloma virus, which also causes cancer, is dealt with in Chapter
15, ¡°AIDS and HIV-The Untold Story.¡± In addition to viruses,
parasites-which are common overseas-also find themselves on the list
of cancer-causing infectious agents. For years, two such parasites
have been known to cause cancer: they are Schistosoma haematobium
and Chlonorchis sinensis. The former is linked to bladder cancer,
while the latter is a known liver cancer risk factor.246 Chronic
bacterial infections such as Helicobacter Pylori can cause cancer
of the stomach and have been linked to lymphoma.247 With a renewed
appreciation for the dangers of infectious diseases, many are
wondering whether meat and other animal products may harbor infectious
agents that could increase cancer risk. I deal with this concern in
Chapter 10, ¡°Animal Diseases and Human Health Risk.¡±
Regular Meals with Nothing Between
Meal frequency has been identified as a risk factor for colon cancer.
A number of studies in different parts of the world demonstrate that
eating meals more frequently leads to an increased risk of colon
cancer.248, 249, 250 Dr. La Vecchia and colleagues in Milan Italy
have published on this subject. Their group found that the risk of
both colon and rectal cancer could be nearly doubled by eating more
frequently, as tabulated in Figure 27: Colon Cancer and Meal
Frequency.251
Four meals per day almost double that imparted increased risk.
Further research estimated that 13 percent of all cancers in Italy
could be prevented if fewer meals were eaten on a daily basis.
(To put things in perspective, it was estimated that another 17
percent of colon cancers were due to high red meat consumption, and
other dietary factors such as low intakes of vitamin C and A accounted
for another 30 percent of colon cancers).
What is the connection between meal frequency and colon cancer risk?
A number of researchers including La Vecchia feel that it has to do
with meals stimulating gall bladder emptying and the release of bile.
Bile can then be converted into cancer-causing compounds, and more
frequent bile release would be expected to increase the exposure
time of the lining of the colon to these toxic bile acid products.
McBurney and colleagues have provided an alternate explanation.
They believe that meal frequency is particularly a problem for those
on a high fat, high protein, low fiber diet. Such eating habits alter
the small intestinal contents and result in rapidly fermentable material
being dumped into the colon at irregular intervals. This material
leads to a surge in the colon¡¯s microbial population that generates
products that are toxic to the colon. More frequent meals stimulate
more frequent masses of this fermentable material entering the colon
(each mass corresponding to a meal), which increases the frequency
that the colon lining is exposed to such toxic products.
The results concur with counsel given years ago by Ellen White: ¡°It
should be shown that to eat two meals is far better for the health
than to eat three.¡±252 She provided further clarification: ¡°Most people
enjoy better health while eating two meals a day than three; others,
under their existing circumstances, may require something to eat at
supper time; but this meal should be very light...¡±253
The medical research presented throughout this book is most consistent
with such an eating style. We should eat a hearty breakfast in the
morning. This is an appropriate time to eat several servings of fruits
and grains, with nuts in moderation. These foods are rich in vitamins,
minerals, and fiber, with no cholesterol. The second meal can be at noon
or in the early afternoon. This may sound like an impossible eating
style for many people-and it may not be permitted by your work schedule.
However, if you have the ability to implement such a program, I have
found that most individuals not only adjust to it, but actually thrive
on such a regimen. Optimally, if you do eat in the evening, it should
be a light meal; the heavier the evening meal the greater chance for
weight gain, as illustrated in Chapter 1, ¡°Principles for Optimal
Health.¡± A good example of a light supper would be a meal based on
fruit.
Exercise - A Friend Your Immune System Needs
Exercise and a healthy immune system go hand in hand. Cancer mortality
rates are significantly lower in regular exercisers. A well-publicized
study of Harvard Alumni found that those who burned only 500 calories
or less per week in exercise had 35 percent more cancer deaths than
those expending greater than 2,000 calories per week.254 Deaths from all
causes, including heart disease, were increased by over 60 percent in
the poorer exercisers.
Over 17,000 men ages 30 to 79 were classified according to their level
of physical activity on two separate occasions over a 25 year period.
Those who were highly active (expending 2,500 or more calories per week
in exercise) had 38 to 61 percent less lung cancer than those who were
inactive (only 1,000 calories or less of exercise per week).255 Heavier
individuals who were highly active dropped their colon cancer risk by
44 to 81 percent. Expressed in other terms, their inactive peers had up
to five times the risk of colon cancer. Other studies have also
suggested that physical inactivity increases colon cancer risk.256, 257
Still other studies have linked physical activity to protection from
other cancers. Researchers at the Cooper Clinic in Dallas have found
that those who exercise moderately have only about three-quarters of
the prostate cancer risk experienced by their inactive peers. The high
exercise group fared by far the best; they had only about 30 percent of
the risk faced by those getting little or no regular exercise.258
Exercise¡¯s protective effects extend to women as well. One recent
study found that women who exercise an average of four hours per week
during their childbearing years decrease their risk of breast cancer
by nearly 60 percent. Even those who only had one to three hours per
week of exercise cut their risk by 30 percent compared to
non-exercisers.259, 260
Why does exercise reduce cancer risk? There are several possible
reasons-many of them center around the immune system. For example,
strenuous, sustained exercise stimulates white blood cells to release
a compound called interleukin 1.261 We could expect any vigorous
exercise to accomplish this effect, whether it is gardening, brisk
walking, or dozens of other activities. This is good news because
interleukin-1, in and of itself, is a natural chemotherapy agent.
Beyond this, interleukin-1 stimulates the release of interleukin-2,
which also aids the immune system. These interleukin chemicals
from our white blood cells serve as modulators of the whole immune
system.
Another way that vigorous exercise helps the immune system is by
doubling the blood plasma interferon levels.262 Interferon is another
chemotherapy agent that acts against certain types of cancer such as
hairy-celled leukemia. It also fights chronic viral infections such
as hepatitis B and hepatitis C.
Exercise also increases other critical immune substances, the natural
killer cells.263 Natural killer cells are certain white blood cells
that seem to have a natural instinct to detect abnormal cells and
destroy them. They seem to be especially important in defending us
from cancer.264 Finally, the blood lymphocytes, which are a broad group
of white blood cells that are very prominently involved in the immune
system itself, are increased with exercise.265
Exercise also has the ability to modulate hormonal mechanisms. This
may be important in both sexes at all ages, but has been particularly
noted in young women who exercise vigorously. It is common knowledge
that the hormonal changes from exercise in that group can be so
profound that menstrual cycles can cease.
Although no one really knows how much exercise is optimal regarding
cancer prevention, most experts agree that one of the most important
factors is consistency. Indeed, exercise should be a part of our
daily routine if we are really serious about cancer prevention.
Sunlight in Moderation
Most of the media¡¯s attention has been on sunlight as a cause of cancer,
as well it is-in excess, as mentioned earlier in the chapter. However,
sunlight deprivation increases the risk of cancer of the breast, colon,
and prostate, possibly due to less circulating Vitamin D-3 and its
derivatives.266 The authors of this discovery conclude ¡°that there should
be no broad condemnation of moderate sunlight exposure.¡±267
Sun exposure may actually help prevent colon cancer. Researchers at the
University of Washington studied cancer rates in nine areas of the United
States. They discovered that men from Southern states had much less colon
cancer than Northerners.268 When compared to New Mexicans, men in Michigan,
Connecticut, and Washington had colon cancer rates 50 to 80 percent
higher. The effect also seemed to hold true for women, although it was
not as marked. One explanation for this decrease in colon cancer risk
in southern states is increased sunlight exposure with a resulting
increase in vitamin D levels. Vitamin D appears able to suppress the
growth of cancerous cells.
Stress and the Immune System
To optimally boost your immune system, adequate stress control is a must.
Studies show that people who are not coping adequately with major
stressors in their lives have a much greater chance of developing cancer
or a life-threatening infection. A number of studies have been performed
on people who already have a life-threatening cancer. Although the
specific biologic process of a person¡¯s cancer is the most consistent
factor affecting survival, social support (such as given by a loving
spouse) and a faith dimension (such as prayer) are two relatively
consistent characteristics among long-term survivals of cancer.269
Because stress control is so important, I have written an entire chapter,
¡°Stress without Distress¡± (Chapter 14), on how adequate stress control
can be achieved even by those under very high stress.
Summary of Agents That Prevent Cancer
To close Section II of this chapter, a review of the many actions that
we can take to dramatically reduce our risk of cancer is in order.
And they are all within the scope of practicality. They are not
complicated; they can be implemented into our lives with no additional
cost. For convenience, a summary list of the elements of a lifestyle
that will vastly reduce our risk of getting cancer is shown in Figure
28: Elements of a Cancer-Protective Lifestyle.
As we have seen, antioxidants, selenium, vitamins A, C, and E, and
many phyto-chemicals have been found to have special qualities that
prevent cancer. Fruits and vegetables that contain one or more of
these substances in good quantity are listed in Figure 29:
Cancer-Protective Fruits and Vegetables.
A Personal Cancer-Protective Lifestyle in a Nutshell
The information in this chapter enables us to outline a personal
cancer-protective lifestyle. Such a lifestyle would avoid carcinogens.
In this chapter we have seen that the leading and most common
carcinogen is tobacco. Smokers need to kick the tobacco habit; efforts
should continue to have a smoke-free, tobacco-free society to eradicate
second hand smoke.
Regarding alcohol, the data is all in. We need to stop using alcohol.
Indeed, even moderate drinking increases cancer, and when you consider
that 56 percent of the American population drink alcoholic beverages,
this is no small matter. When we think about alcohol¡¯s carcinogenic
potential and what it is doing in relation to increasing accidents,
homicides, and suicides, we need to choose to abstain and encourage
others to do the same-it is the only option that makes sense.
If we really want to maximize our personal cancer-protection effort,
we must choose the foods that will work for our benefit and eliminate
the foods that are working against us, as the many studies cited in
this chapter have shown. We have seen that societies that regularly
consume meat, high fat dairy products, and saturated fats associated
with them, have the highest rates of cancer. Changing our diet does not
mean cutting down on red meat and eating instead more chicken, turkey,
or fish, which contain many toxins, viruses, and other potentially
dangerous substances. There is no net gain from that approach; it
still has many of the original hazards. Only by changing from the
typical American animal-based diet to a plant-based diet (such as in
China and many other countries in the world who have the lowest
cancer rates) will we achieve the results we want. Eating freely of
fruits, grains, vegetables, and nuts in moderation, prepared in a variety
of ways, offers us the most healthful diet in the world. It was the first
diet recorded in the history of man and is still the best that we know of
today. It not only eliminates a host of cancer-causing substances but is
also ideal for maintaining proper weight. It boosts the immune system
by making use of vitamins A, C, and E and other very important protective
phytochemicals and fiber.
Coupling this diet with regular aerobic exercise will boost the immune
system even further. Rounding out the program with adequate stress
control, moderate sunlight, weight control, and decreasing snacks and
meal frequency will maximize the preventive potential.
Anything worth doing is worth doing right. All of us are indeed capable
of changing our behavior for the good, especially when we know what
benefits may result. The personal stakes are high-it is a life and
death matter-my life, your life, and the lives of our children and
loved ones. The message is clear and it calls for action. The time to
0act is now.
The Best Kept Secret for Preventing a Catastrophic Disease
Think of what would happen if tomorrow-after all the billions of dollars
spent on cancer treatment research-a miracle cancer pill was finally
discovered. And it¡¯s promise was not false: it fully cured 90 percent
of all cancers! No doubt the drug would make headlines. The company that
developed it could put a huge price tag on it. After all, think of all
the money it would save on surgeries, radiation therapy, and chemotherapy
hospitalizations. No doubt it would have its share of side effects-all
drugs do. But who cares about side effects when you have cancer and the
cure is just a pill away!
The drug developers would probably receive the Nobel Prize for their
work. It would not be surprising if the President of the United States
invited the chief investigators to a special reception at the White
House. What a cause for rejoicing this truly would be. All the hoopla,
the national fame, and the honor bestowed upon the participants would
be tremendous-as well it should.
But stop for a minute. There is no sign that any drug like this is on
the horizon. Furthermore, what is really more important, prevention or
cure? We are all aware of the old saying, ¡°An ounce of prevention is
worth a pound of cure.¡± But do we really live as though we believe it?
Even if that imaginary cancer cure pill really were developed, think
of all the problems that cancer causes-before it is even diagnosed:
all the medical bills, time lost from work, and family stress, not to
mention the pain and suffering caused by the disease. Even if there
were a cure for every single cancer, prevention would still be much
cheaper and much more desirable and pleasant. But in an era when,
despite all the billions of dollars that have already been spent on
hopes of that elusive wonder cancer drug, and we are still nowhere
close to such a magic cancer cure,270 how much more important is the
prevention of cancer?
As hard as it may be to believe, in a sense, the magic cancer pill
has been found. Research has revealed that we now have up to a 90
percent effective ¡°cure¡± for cancer in the form of a comprehensive
cancer-preventive lifestyle. But there have been no headlines, no
hoopla, no presidential invitations, no Nobel prizes. In fact,
hardly anyone even knows about this powerful lifestyle. Indeed, there
are many people who know various aspects of the program I have
described in this chapter. Many are aware of the importance of
stopping smoking, or exercising, or eating more fruits and vegetables.
Yet, regarding the whole package that can give such amazing results,
most of the general public is totally unaware. Unfortunately, this
includes health professionals. Although most are aware of some of the
elements I have discussed in this chapter, few are aware of the power
of the comprehensive lifestyle approach to cancer that has been
presented.
This lack of awareness is even more striking in light of the ¡°age of
information¡± in which we live. We should be clearly broadcasting this
comprehensive approach to cancer prevention on every television and
radio station; we should present it graphically and powerfully in
every newspaper, magazine, and computer news service. This lifestyle
should be the subject of a massive government educational program.
If such happened tomorrow, and the American public embraced the new
way of living that was championed, the number two killer in America
would soon be relegated to the bottom of the 10 leading causes of death.
The pain, suffering, productive work lost, family heartache, doctor
and hospital visits, not to mention their associated costs, would be
greatly diminished.
But for the most part, the media, researchers, health educators, and
Presidents have been deathly silent in promoting a comprehensive
lifestyle program for cancer prevention. They, like most of society,
declare war on cancer by focusing energy on elusive treatments and
narrow preventive approaches, when a comprehensive preventive lifestyle
is right at our finger tips. Is it simply ignorance? Or is it possible
that many of our leaders, scientists, and media spokespersons are not
willing to make bold lifestyle changes themselves (so long as they are
feeling well)-and thus would be uncomfortable in challenging anyone
else to adopt such a way of living?
Is there a fear of backlash from powerful commercial interests if the
optimal cancer preventive lifestyle is advocated? (The message of
this chapter will not likely be popular with the likes of the alcohol,
meat and dairy industries, etc.) I honestly do not know what all the
impediments are, but I do know that now is the time to get the word
out about this total lifestyle. And now is the time for each one of us
to become a living example of the power of such a lifestyle to combat
America¡¯s fearful number two killer.
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