Fish Oil and
Cancer: The word itself causes a strong reaction in most of us. It evokes
images of a slow, painful death. Each year over 1.3 million Americans are
diagnosed with cancer. Every minute one person dies from this disease.
Traditional medicine offers us surgery, chemotherapy, and/or radiation as
treatments. But these painful, toxic and sometimes even cancer-causing
treatments only offer a less than 33% cure rate.
Are there any ways we can
prevent and fight cancer? Statistical data shows us that about 60% of women's
cancers and 40% of men's cancers are related to nutritional factors. At least
40% of cancer patients die from malnutrition, not from the cancer itself.
Based on numerous scientific studies, cancer researchers around the world have
begun to believe that certain natural nutrients can prevent and sometimes cure
cancer. This gives new hope for those suffering from cancer.
History of The Magic Fish
Interest in the potential benefits of fish oils emerged from the observation
that cardiovascular diseases and cancer incidence rates are generally low in
the Eskimos of Alaska and Greenland. (1, 2) These populations eat a diet high
in fish fat and low in carbohydrates this is contrast to the diets of North
American and other western populations who also consume a high fat diet but
mostly from animal and vegetable oils.
Animal fats contain saturated
fatty acids. Vegetable oils, like corn oil and safflower oil, contain high
levels of polyunsaturated fatty acids of omega-6 type. Because a high intake
of animal fat is related to an increased risk of heart disease, and intake of
polyunsaturated fatty acids (such as corn oil) can lower cholesterol levels
(believed to be beneficial to heart disease prevention), Americans tend to
consume more vegetable oil than animal fats.
Researchers found that fish oil
can significantly inhibit cholesterol production. The beneficial effects of
fish oils come from their unique composition of high levels of the omega-3
polyunsaturated fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic
acid (DHA). Additionally, these omega-3 polyunsaturated fatty acids can
increase the HDL (so-called good cholesterol) levels. Fish oil also provides
anti-inflammatory and anti-aggregatory effects which play a crucial role in
the formation of atherosclerosis and thrombosis. Due to these findings, it is
believed that both healthy people and heart disease patients can benefit from
fish oil supplementation.
Fish Oil And Cancer
One exciting aspect of fish oil is its significant inhibitory effects against
various human cancers in animal models, including breast cancer, colon cancer,
skin cancer, pancreatic cancer, prostatic cancer, lung cancer, larynx cancer,
etc. (3-8) Unlike fish oilwhich is high in omega-3 polyunsaturated fatty
acidsfats that are high in omega-6 polyunsaturated fatty acids (like corn oil)
can increase tumor growth. Using a chemical carcinogen-induced cancer model,
researchers found that a high intake of fish oil significantly lowered the
cancer incidence in animal studies as compared to animals fed either low fat
diets or high corn oil diets. (9) By implanting human tumors into
immune-deficient (nude) mice, researchers have found that a high fish oil diet
can slow tumor growth. (9) These results suggest that fish oil can be used for
both prevention and treatment of cancer.
Proposed Mechanisms For Fish
Oil's Tumor Growth-Slowing Effects
Although there is no clear mechanism to explain fish oil's significant
anticancer effects, researchers have uncovered several potential models of
1. Alteration of cell membrane composition. After ingestion, fish oil is
easily incorporated into cell membranes (especially tumor cells) which changes
the cell membrane composition. This alteration will change the cell's response
to growth factor, hormones, antibodies, etc.
2. Inhibition of prostaglandin production. Prostaglandin can stimulate tumor
cell growth. Fish oil can inhibit the enzyme responsible for prostaglandin
synthesis called prostaglandin synthase. After a high intake of fish oil,
prostaglandin (especially in the tumor cells) is decreased significantly,
which in turn, slows tumor growth.
3. Immune system stimulation.
4. Hormone profile changes, which may provide important benefits for hormone
-related cancers like breast cancer.
5. Tumor cell toxicity, probably by causing lipid peroxidation in the tumor
Fish Oil And Metastasis
One of the big concerns in cancer treatment is metastasis the process by which
tumor cells spread from the primary location to distant parts of the body.
Metastasis is increased by a high intake of omega-6 fatty acids (i.e., corn
oil), but is inhibited by fish oil. Using a nude (immune deficient) mouse
implanted with human breast cancer, researchers found that feeding a high fish
oil diet (23%) to the mice significantly reduced human breast cancer cell
metastasis to the regional lymph nodes and lungs. (10) This indicates the
significant beneficial effects of fish oil supplementation in cancer
Fish Oil And Cachexia
Over 40% of cancer patients died from cachexia, not from cancer itself.
Cachexia is the malnutrition and wasting away caused by cancer. Cachectic
patients are characterized by extreme weakness and emaciation. If we can
overcome this cancer -induced malnutrition, we can potentially save or prolong
the life of over 40% of cancer patients. Researchers in England found
that fish oil could significantly prevent cachexia in an experimental model.
Feeding the animals a high fish oil diet (compared to either a low fat diet or
a high corn oil diet), significantly decreased the loss of body weight caused
by cachexia, and at the same time, muscle mass was significantly increased.
Additionally, fish oil showed a dramatic anti-cancer effect which was as
effective as some chemotherapy drugs. The researchers concluded that fish oil
could significantly prevent the cachexia caused by cancer, and at the same
time, provide potent anti -cancer action. (11)
Fish Oil And Chemotherapy
Researchers at Allie M. Lee Cancer Research Laboratory at the University of
Nevada, Reno first declared that fish oil supplementation may be of benefit in
cancer chemotherapy. By using a human breast cancer model, they found that
feeding the animals a high fish oil diet both slowed the tumor growth and
increased the tumor responsiveness to chemotherapy drugs by altering the drug
activating systems. They also found that a high fish oil diet can
significantly protect the host animals against the toxicity of chemotherapy
drugs. The researchers concluded that fish oil supplementation will provide a
three pronged attack on cancer:
1. A strong anticancer effect.
2. Protection from chemotherapeutic drug toxicity.
3. Cachexia prevention. (12,13)
As a dietary supplement, fish oil shows significant benefits in cancer
prevention and treatment. Due to the high incidence of cancers and the
relatively low levels of fish oil intake in North American, it is likely that
most people can benefit from fish oil supplementation.
No information in this article
is intended as a prescription. If you are concerned about preventing or
treating cancer, please consult your physician.
source of nutrients and supplements.
did we qualify them ?
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