Lower Cholesterol
for Improved Cancer Survival
More than 30 years of medical practice have left me with many impressions
concerning the treatment of diseases. I have hesitated to share some
of these views because they have yet to be fully established as beneficial
by proper scientific research. Even so, I feel the time has now come
to discuss the topic of cholesterol for cancer patients. Fully realizing
there is still much research to be done; I leave open the option for me to
modify my opinion on this subject in the future.
Cholesterol in the diet and the cholesterol in the body (as reflected by
the blood cholesterol) seem to be tied to the development and progression
of cancer.1-5 Some research suggests high blood cholesterol
levels may also be tied to a poor prognosis.2,4,5 Over the
years, I have noticed that too many of my cancer patients have had high
cholesterol levels. More concerning, too many times I have also observed
these elevated levels are resistant to the cholesterol-lowering benefits
of a low-fat, no-cholesterol diet. These observations and evolving
scientific research has caused me to become more aggressive when treating
my cancer patients � similar to the way I treat my heart patients. (See
my September 2002 Newsletter).
Early Research Shows Diet-Cancer Connection
The
first published connection between a high-fat diet and cancer was made in
1930 by Watson and Mellanby in their paper which appeared in the
British Journal of Experimental Pathology.6 A diet high
in butter fed was found to accelerate the growth of skin cancer in mice
treated with cancer-causing tar. Subsequently, many scientific studies
have shown the cancer-promoting effects of excess calories, fat, and
cholesterol � hallmarks of the American diet.7
One
of the first studies to show the benefits of lowering cholesterol for
cancer was also performed on mice. In 1966 Littman published his work in
the journal Cancer Chemotherapy Reports.8 A
cholesterol-free, fat-free diet retarded the growth of cancers (sarcomas
and carcinomas) and prolonged the survival of these mice with cancer. The
diet cut the tumor growth rate in half (compared to controls) and survival
time was often doubled. The benefits from the diet were attributed to the
cholesterol-lowering effects of the cholesterol-free, fat-free diet
(rather than the accompanying weight loss). Also, the absence of
cholesterol in the diet appeared to be more important than the absence of
fat, because adding cholesterol back to the diet completely reversed the
growth inhibition of this approach. The use of cholesterol lowering
agents along with a cholesterol-free diet caused even further tumor
inhibition.
How Does Lower Cholesterol Benefit Cancer Patients?
Cholesterol is required for the growth and survival of cells.9
There is evidence that cancer cells have even higher demands for
cholesterol than normal cells. Furthermore, growing cancer cells lose
their capacity to synthesize cholesterol, and therefore become dependent
upon outside sources of cholesterol � sources such as the diet.
Deprivation of abundant sources of cholesterol slows growth of the tumor,
reduces the spread of cancer (metastasis), and prolongs survival of the
animal.10
In
practical terms, the overall nutritional qualities of a no-cholesterol
diet have a major impact on health. Plant foods have no cholesterol � so
by definition in the real world this means a diet that looks a lot like
the McDougall diet.
Practical Experience of Cancer Diet Therapy
Worldwide, the intake of cholesterol in the diet correlates directly with
the population risks of developing common cancers � like breast, colon and
prostate cancer.1 Furthermore, worldwide, people with cancer
who follow diets lower in fat and cholesterol and higher in plant foods
have a better survival than those on richer diets, loaded with these
harmful ingredients.11,12 Multiple studies have been published
on the benefits of low-fat, low-cholesterol, high-plant food diets on
various kinds of cancers.13-17 Many so called �alternative
therapies� for cancer have as their basic treatment a low-fat,
low-cholesterol diet. These include the Macrobiotic diet, the Gerson
Therapy, the Livingston-Wheeler treatment and the Ornish Diet for prostate
cancer.18-20
In
most cases when cancer is in an advanced stage it is fatal; however, a
patient should never give up hope. There have been cases where otherwise
terminal patients have had a miraculous recovery � described in the
medical business as a �spontaneous remission.�21-24 Logically,
a patient�s chance of such a miracle happening would be more likely to
occur if he or she were in good health and well nourished, than not.
Cholesterol Intervention with Medications
Recommending a healthy low-fat, low-cholesterol diet to patients, even
those with serious diseases, like cancer, should be done routinely by
doctors. After all, if you believe diet causes, or at least contributes
to the cause of, common cancers, then it makes no sense to �throw gasoline
on a fire.� At the very least the patient with cancer will be healthier �
and no harm is done.
However, when it comes to medications then there are always side
(undesirable) effects and costs; hopefully, along with real benefits.
Therefore, I have hesitated until now to make recommendations about
cholesterol-lowering medications to my patients with cancer. Let me
explain some of the evidence causing me to now act otherwise.
Cholesterol binding resins:
One
class of cholesterol-lowering medications works by binding cholesterol and
cholesterol precursors (bile acids) in the intestine, preventing their
absorption into the body and causing their elimination with the stool.
One of these medications, called cholestyramine (Questran), has been
reported to cause regression of prostate cancer in 3 men.25
During a large study of patients for heart disease treatment, the
cholestyramine and placebo groups had similar 13.4-year mortality rates
from cancer, other medical causes, and trauma and similar cancer incidence
rates.26 However, the incidences of benign colorectal tumors
(50 vs 34), cancer of the buccal cavity and pharynx (eight vs. two),
gallbladder disease (68 vs. 53), and gallbladder surgery (58 vs. 40) were
non- significantly increased in the cholestyramine group. Therefore, this
agent is not without risks and would be best used by patients with cancers
not related to the gastrointestinal tract.
Statins:
Statins (Mevacor, Lipitor, Pravachol, Zocor, and Lescol for example) lower
cholesterol by inhibiting production in the liver. These medications have
been shown to lower cholesterol by 20 to 60% and also reduce the risk of
death from heart disease and stroke.27,28 I prescribe these
kinds of medications often for my patients at high risk of heart disease
(see my September 2002 Newsletter). They have a record of being quite
safe with few side effects. Pravachol is currently my favorite statin
because � even though all statins lower cholesterol -- this kind of
medication appears to be most effective at lowering the risk of heart
disease.29 It also poses less risk of serious complications
such as muscle damage. There is good evidence that people on these kinds
of medications should also be taking a dietary supplement called Co-enzyme
Q 10 (ubiquinone 60 mg qid) to help prevent muscle damage.30
In
animal studies, Mevacor (lovastatin) has been found to inhibit tumor
growth and spread (metastasis) in mice with breast, lung, and melanoma
cancers.30-32 Cancer growth inhibition has also been seen with
human cancer cells studied in a laboratory.33 Although large
studies on heart disease patients have failed to show a reduction in risk
of cancer, there is one very encouraging study of patients with liver
cancer treated with Pravachol 40 mg/day.34 Survival was
doubled.
My Recommendations
The
decision to treat is based on a risk versus benefit calculation. All
cancer patients should be on a low-fat, no-cholesterol, plant-based
diet.* There are numerous qualities of this kind of diet that prevent and
slow the growth of cancer (See the McDougall Program for Women
book). They should also exercise and give up bad habits like smoking. A
healthy diet and lifestyle provide all benefit at no risk. All other
treatments, such as surgery, radiation, and chemotherapy, must be decided
upon based on their own merits. I strongly encourage you to do research
at the National Library of Medicine at
www.nlm.nih.gov (free). I have also discussed many of these treatment
issues in my books and newsletter articles � especially the McDougall
Program for Women.
I
believe people with cancer should make all reasonable and necessary steps
to lower their cholesterol levels to 150 mg/dl or lower � the same ideal
value I have encouraged for people in general, and especially those
interested in heart disease, prevention and treatment. If with diet alone
a cancer patient fails to reach this goal, then cholesterol-lowering
medications � like statins and/or cholestyramine � should be the next
step. I believe the benefits outweigh the risks for most patients.
Someone diagnosed with cancer has every reason to be as healthy as
possible and this means taking the best care of himself � and never giving
up. I believe, based on my experience and what the scientific literature
tells, that most cancer patients can prolong their lives dramatically by
making the right decisions. By slowing tumor growth my hope is that
recurrences for all my patients can be staved off until their 90th
birthdays.
*
One word of caution if you change to a healthy diet. Weight loss often
becomes an issue for cancer patients. Doctors caution against cancer
patients losing weight, because in the doctor�s mind weight loss means the
terminal days have arrived. However, this is not the case when weight
loss is due to becoming healthier with a plant-based diet and exercise.
Be prepared and guard against this confusion.
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