Flax Oil & Prostate Cancer:
Flaxseed Oil (ALA) & Prostate Cancer
Witch Hunt Or Cause For Concern? By Udo Erasmus
Background, And Abbreviations Used In This Article:
EFAs: Essential Fatty Acids are substances from fats that must be provided by foods because the body cannot make them, and yet must have them for health.
EFAs Exist In Two Families: omega-3 (n-3) and omega-6 (n-6).
From These Two, the body can make several derivatives, hormones, and other active substances.
N-3: Omega-3 Fatty Acids Include
- 1. ALA (alpha-linolenic acid; abundant in flax, and present in smaller quantities in hemp, walnut, soybean, and canola); given enough ALA to start with, the body converts ALA into SDA, EPA, and DHA in various tissues, according to need;.
- 2. SDA (stearidonic acid; present in a few exotic seeds)
- 3. EPA (eicosapentaenoic acid; parent of Series 1 eicosanoid hormones; found in fish oils)
- 4. DHA (docosahexaenoic acid; the major brain n-3; found in fish oils)
ALA: Alpha-Linolenic Acid is the (n-3) EFA. It is sometimes shortened to LNA. Others shorten it to ALNA. ALA is very fragile to destruction by light, oxygen (air), and heat, and must therefore be protected from these destructive influences. If this is not done, ALA molecules are changed from natural and beneficial, to unnatural and toxic. ALA is destroyed about 5 times faster than LA, the n-6 EFA. ALA is deficient in the diets of most people in affluent societies. Its intake has decreased to less than 20% of what was present in common diets 150 years ago, mainly due to decreased use because of its fragility.
N-6: Omega-6 Fatty Acids Include
- 1. LA (linoleic acid; abundant in safflower, sunflower, and corn; present in medium quantities in soybean, sesame, pumpkin seed, and almond; present in small quantities in canola, peanut, and olive); given enough LA to start with, the body converts LA into GLA, DGLA, and AA in various tissues, according to need;
- 2. GLA (gamma-linolenic acid; present in evening primrose oil);
- 3. DGLA (dihomogamma-linolenic acid; parent of Series 1 eicosanoid hormones);
- 4. AA (Arachidonic acid; the major brain n-6; parent of Series 2 eicosanoid hormones; found in meat, eggs, and dairy products).
LA: Linoleic Acid is the omega-6 (n-6) EFA. LA is abundant in the diets of most people in affluent societies, its intake having doubled during the past 100 years due to increased use of corn and safflower oils. LA is sensitive to destruction by light, oxygen (air), and heat, and should be protected from these destructive influences. If this is not done, LA molecules can change from natural and beneficial, to unnatural and toxic. Introduction In their frenzy to boost sales, manufacturers of flax oil have greatly promoted (perhaps even over-promoted) its benefits but have not addressed the down side of flax oil. Flax oil has benefits, but it also has shortcomings. Overlooked, these can lead to serious health problems. What are these shortcomings, and what are the problems that can stem from excessive use of flax oil?
A recent review article points out that prostate cancer is increasing, and is the second leading cause of cancer deaths in the Western world. The etiology of prostate cancer remains unclear, course and progression are unpredictable, and definite treatment is not yet established. Lifestyle and diet could contribute to the progression from small, latent, non-metastatic tumors to clinically significant, invasive, metastatic lesions.
Research on the involvement of fats and fatty acids in prostate cancer has been inconsistent. Most of the information available comes from epidemiological studies. Data from animal and human studies are limited. There is the further problems that results from animal studies, especially rats, cannot be automatically generalized to humans, because rats and humans metabolize fats quite differently. Also, rats don't fry steaks, don't use salad dressings and mayonnaise made with oils that have been highly processed, and don't eat butter that has been exposed to light and air, sometimes for weeks. The reason I make this point will become clear a little later.
Studies done on cell cultures do not take into account the effects of fats on other organs that can affect tumor development and growth. In particular, some fatty acids up- or down-regulate the functions of genes, and it appears that some fatty acids also change the effectiveness of hormones even if they don't change hormone levels present in tissues. Within this context, the suggestion has been made in published literature that flax oil should not be used because it can increase prostate cancer. The Prostate Forum2 lists six studies showing positive correlation between ALA (in serum, adipose tissue, and red blood cell membranes) and prostate cancer. Of the six studies, one showed no correlation. One found a small (not statistically significant) positive correlation. Four studies found a strong positive correlation between ALA and prostate cancer. At least two other studies have also shown a correlation of alpha-linolenic acid with increased prostate cancer. According to Prostate Forum, several labs have found that ALA is one of the most powerful growth stimulants for human prostate cancer cells. The Prostate Forum has recommended against the use of flax oil by men with prostate cancer. Since flax oil is the richest readily available food source of ALA, the reasoning goes, this oil should cause the most prostate cancer. Sources of ALA Used Studies that Support One-Sided View
The "ALA" in population (epidemiologic) studies comes from two main sources: vegetable oil, and red meat animal products. Both were shown to correlate with similar increases in prostate cancer. In cell studies, chemically "pure" fatty acids are usually used. The sources of ALA, the n-3 EFA that is 5 times more easily destroyed by light, oxygen, and heat than LA (the n-6 EFA), come from foods that have been treated with great carelessness. Let me illustrate this point. In one of the epidemiologic studies, the sources of ALA were listed. They include red meat and bacon (both are usually eaten fried), salad dressing and mayonnaise made from soybean and/or canola oils which have been destructively processed by degumming, refining, bleaching, and deodorizing (so-called "RBD oils"), and butter (which is poorly protected from light and air between the time the cow is milked until the butter is consumed). In addition, beef and butter contain trans-fatty acids, and these correlate with increased cancers including prostate cancer.
One of these trans-fatty acid is Conjugated Linoleic Acid (CLA) which is also sold as a supplement in capsules.
- Interestingly, a study done with flax grain has shown that flax inhibits the growth of prostate cancer.
- Another study showed that prostatic alpha-linolenic acid was lower in cancerous prostate glands that exhibited perineural invasion, seminal vesicle involvement, and stage T3 tumors. In a review article on n-3 fatty acids and cancer, the author makes the observation that the effect of n-3 polyunsaturated fatty acids (PUFAs) on cancer depends on background levels of n-6 PUFAs and antioxidants, and this could account for previously inconsistent results in experimental carcinogenesis. He also makes the observation that n-3 PUFAs appear to be excellent substrates for lipid peroxidation in situations where an oxidative stress is involved, such as in the action of several cytotoxic agents in the treatment of cancer. Other researchers found that the ratio of n-3/n-6 PUFAs decreased in the following order: normal, benign prostatic hyperplasia, and prostate cancer. This indicates that n-3 inhibit prostate problems. They conclude that the ratio of n-3/n-6 may have an important association with the benign and malignant statue of prostatic disease. Yet other researchers suggest that among fatty acids, the n-6 derivative arachidonic acid (AA), delivered in larger than normal quantities to prostate cancer cells in tissue culture by LDL cholesterol via over-expression of its receptor (LDLr), increases the activity of the cancer-related genes c-fos and cox-2.
- In 1994, one review suggested that for prostate cancer, fat consumption should be decreased to 15% of calories. The antioxidants selenium and vitamin E should be supplemented, and a soy product should be used. Another study shows that the same n-6 derivative AA, stimulates growth and division of prostate cancer cells (both hormone-sensitive and hormone-insensitive) by increasing lipoxygenase enzyme activity (increasing inflammation). The researchers show that if you block this enzyme, the prostate cells self-destruct (apoptose) very rapidly. This could be achieved by inhibitor molecules, by decrease of AA in the medium (or diet), and by increase of n-3 fatty acids that inhibit the production of AA.
- One further study showed a positive association between prostate cancer and animal fat, as well as the n-3 EFA (ALA). It also showed an inverse association between the antioxidant vitamin C and prostate cancer. A study in 1985 showed that GLA, ALA, AA, and EPA all killed prostate cancer cells in tissue culture, but did not affect the normal cells with which they were cultured. The latter continued to grow normally. When essential fatty acids were not present, the prostate cancer cells overgrew the normal cells.
- In 1991, the view from research was that diets containing high levels of n-6 fatty acids enhance tumorigenesis in animals, and that diets with equivalent levels of n-3 fatty acids diminish tumorigenesis.
- A 1999 publication concludes that the combination of fatty acids makes a difference. In this study, GLA, ALA, and EPA increase the death of prostate cancer cells. A slight increase of cancer cell death was obtained when ALA was combined with AA, OA, or GLA. But ALA with LA or EPA had no effect or even decreased prostate cancer cell deaths.
- A study with another prostate cancer cell line reports that GLA and EPA, which inhibit an important enzyme in carcinogenesis (urokinase-type plasminogen activator [uPA]), suppress cell proliferation (growth and division). Low EPA and high uPA levels have been reported in cancer. ALA, LA, and AA also suppressed cell proliferation in this study.
- Another study found that rats grow faster when vitamin E is given along with linseed oil (which is refined, bleached, deodorized flax oil), grow slower if linseed oil was given without vitamin E, and grow even slower in the presence of pro-oxidant.
- A study in women found that only ALA, but not saturates, monounsaturates, or long chain polyunsaturates n-3 or n-6, had a protective effect on breast cancer.
- A 1999 study found that mutation of the androgen receptor (AR) gene as a cause of prostate cancer is rare, and that over-expression of the AR gene seems to be the most common alteration in hormone-refractory prostate cancer. The question left unanswered is what causes this over-expression.
- A study published in 2001 concludes that a high intake of both red meat and dairy products is associated with a two-fold increase in risk of prostate cancer. The reason for the association with red meat remains unexplained.
- Another 2001 study found that a short term (3 month) low fat, fish oil (EPA and DHA) enriched diet increased the n-3/n-6 ratio in plasma and adipose tissue. Also, cyclooxygenase (COX-2) expression decreased in 4 of 7 patients.22 COX-2 produces inflammation, which is involved in cancer.
- Finally, a study found that DHA and EPA decreased expression of several genes that are up-regulated by androgen in LNCaP prostate cancer cells. They thereby reduced androgen-mediated cell growth of this prostate cancer cell line. DHA increased the proto-oncoprotein c-jun.
Science has become so technical that we're nearing the Tower of Babble, where everyone talks and no one understands. We get lost in a sea of details, lose our common sense, and only drug manufacturers, whose products suppress symptoms without effecting cure, benefit from the confusion.
It is not difficult to see that these various findings by researchers must leave most people confused. The problem with these studies is the isolation in which they are carried out.
In Nature, n-3 and n-6 EFAs are undamaged because they have not been destructively processed, and are accompanied by by many other oil-soluble substances, including antioxidants, mineral, vitamins, phytosterols, lecithin, and more. Many of these substances have anti-cancer or immune-enhancing effects in the body.
In the lab, substances are isolated into chemically pure forms, which are easier to manage, but in their effects on the body are far different from whole foods with their thousands of synergistic ingredients.
We should address the contradictory findings of the studies by applying some common sense. That is what we will attempt to do next.
N-3 related Causes of Prostate Cancer: Common Sense EFAs are chemically very active molecules. They are required for vital functions in all cells and tissues. We cannot live withut them. They must be provided by foods.
The big question that begs to be answered is why substances that are absolutely required for health can at the same time give you cancer and kill you. It doesn't make sense. So there must be other issues that are being ignored when professionals (untrained in nutrition), in this case of ALA and flax oil, issue an edict against their use.
Here are my thoughts on the issues that must be considered in trying to find out what is happening in the effects of EFAs in prostate cancer, and how to avoid or fix it. Processing damage of ALA, the most fragile of essential nutrients, must be considered as a possible cause of increased prostate cancer. As ALA consumption increases, so does the amount of damaged, toxic breakdown products of ALA resulting from careless treatment of this essential nutrient. Unless care is taken to protect ALA from being damaged and thus made toxic by light, air, and heat, health problems based on the toxicity of altered molecules of ALA should be expected to accompany ALA intake.
According to one of the above studies, which compared high and low intakes of ALA in humans, the strongest risk factor was the consumption of red meat. Red meat is rich in iron, which along with other metal elements such as copper, has strong pro-oxidant action that can speed up the damage done to EFAs by light, oxygen, and heat. That's true outside the body as well as inside the body.
Because of ALA's far higher fragility, we should expect ALA to be damaged far more extensively than LA. As a result, far more toxicity should come from diets with higher ALA intake in association with pro-oxidants that lead to free radical formation and oxidation products.
Related information shows that red meat consumption correlates with increased cancer in general. White meats from chicken and turkey, which contain as much ALA as red meat does, show less of a correlation with cancer than red meat.
High fat fish, which contains more n-3 than red meat, and in the form of EPA and DHA, that are even more fragile to damage done by light, air, and heat, lowers cancer risk factors. And raw high fat fish, in the form of Japanese sushi or sashimi, correlates with the least cancer. These findings do not provide proofs, but the trend is obvious. It suggests that ALA or the other n-3 do not increase prostate cancer, but that the n-3 molecules damaged during commercial processing and food preparation-cooking, frying, and especially barbecuing-may well be the reason for the increased cancer seen in some of the studies.
A question that is not often discussed is the effect of cytotoxic (cell-toxic) chemicals used in the treatment of cancer. Some of these appear to be able to damage (oxidize) n-3 fats when both are given to a cancer patient. Antioxidant depletion research has consistently shown that increased intake of EFAs increases the need for antioxidants.
EFAs are high-energy fuel. In the body, they build a strong fire. A strong fire throws more sparks than a weak one. Those who fear the EFAs suggest that we should lower intake. That means, turn down the fire. Taken to its logical conclusion, that would mean that we should put the fire out, because if there's no fire (i.e. we are dead), there'll be no sparks that can do damage. Then we need no more antioxidant spark control, because the fire's out. What would be the point of that?
A more viable solution is to make the strongest possible fire of energy (life), and to make sure that there's good spark control. Antioxidant protection should accompany our increased intake of EFAs. N-3 fatty acids, being more chemically active than n-6, probably require a higher antioxidant intake for spark control. But higher n-6 intake too, requires more antioxidants.
The richest source of antioxidants is fresh green vegetables. They make hundreds of different kinds of antioxidants. The seeds themselves are also rich sources of antioxidants for their own (and if we eat them, our) protection. Oils made with health in mind contain natural antioxidants appropriate for their EFA content. Oils made with shelf life in mind have had these antioxidants removed. That's why synthetic antioxidants (BHA, BHT, and others) are added to replace the natural antioxidants that were removed by refining, bleaching and deodorizing. And research has shown that 400-800mg of vitamin E daily reduce cardiovascular risk by over 75%, while 200ug of selenium daily reduce cancer risk by over 50%. These two powerful antioxidants, as well as zinc, manganese, vitamin C, vitamin A (or carotene), sulfur-containing amino acids, alpha-lipoic acid, garlic, and onions, all provide antioxidant protection to the body.
Certain herbs, and mushrooms also help. A Lack of Phytosterols have been shown to inhibit many cancers. One of the pioneers in natural treatments of cancer, Dr. Emanuel Revici, worked from the hypothesis that lack of EFAs, and lack of phytosterols cause cancer. He successfully reversed cancer with EFAs and/or sterols. His methods reversed the cancers of many patients, and Revici himself was a testimony to his own methods. He died a few years ago at the age of 102. Unfortunately, much of his work is now lost.
Phytosterols are found in the membranes of all cells of all plants, in seeds and in unrefined oils, but they are not found in animals. They inhibit sterol reactions: cholesterol, and the male and female steroid hormones androgen (testosterone), estrogens (estradiol, estriol, progesterone), and corticosteroids (aldosterone, cortisol, and others). They therefore slow down the growth of steroid hormone-specific cancers, including some types of prostate cancer. Too much ALA in relation to LA is another factor that needs to be addressed. N-3 and n-6 EFAs compete in the body for space on the enzymes that convert them into derivatives and eicosanoid hormones. Hence the ratio between them must be such that adequate amounts of both are converted. A ratio of 2:1 of n-3 to n-6 will do this. So will a ratio of 1:4. In healthy people, a wide range of ratios is able to maintain health. In people with degenerative conditions, emphasis on n-3 seems to be more effective. That's because n-3 intake has dropped to 1/6th of what people obtained in their diet 150 years ago, while n-6 intake has doubled over the past 100 years. This problem can be caused by flax oil. Flaxseed, used as the exclusive source of fats in the diet, will eventually lead to n-6 deficiency. Both flax and flax oil have an n-3: n-6 ratio of 3.5 or even 4:1. Using such a ratio will result in the n-6 EFA being crowded out from the enzymes. And that will lead to n-6 deficiency symptoms. The list of n-6 symptoms is long but, relevant here, is the fact that n-6 deficiency leads to deterioration of immune function, which in turn can lead to increased cancer growth. A comprehensive list of n-3 and n-6 deficiency symptoms is found in the book Fats That Heal Fats That Kill.
High n-3 with low n-6 can also be seen in other cancers. I have seen a reference in that regard for breast cancer. Other toxic materials that accompany EFAs can also affect cancers. For instance, antibiotics used in feeds end up in meat. These antibiotics can inhibit immune function. Hormones and pesticides contained in meat, butter, and other dairy products can also affect cancer outcome. In vegetable oils, the packaging can also be an issue. Plastics, which contain fillers, plasticisers, stabilizers, mould releasers, and other industrial chemicals may be able to dissolve in oils, and then have an effect on the body that accompanies the oil. Packaging oils in clear glass or plastic, especially those that contain n-3 (canola and soybean) is an antiquated and inadvisable method, because it exposes the oils to the destructive influence of light. In some plastics, heavy metals like lead have been found. Carbon Black, a cousin of soot used to make some plastics opaque to light, contains PAHs (Polycyclic Aromatic Hydrocarbons) that form when carbon reacts with itself in a situation of incomplete burning. PAHs are carcinogenic. Oxidative stress from cell-killing (cytotoxic) chemicals-industrial (e.g. pesticides) or even pharmaceutical (e.g. drugs used to treat cancer and other conditions) can affect the action of n-3 (and other nutrients) in the body.
Since n-3 are natural and essential, and drugs are unnatural and toxic, preference should be given to natural treatments whenever possible. The practice of "complementary medicine", in which natural as well as unnatural treatments are combined, in such cases becomes "contradictory medicine". To be healthy, we must not poison our genetic program and its work, and we must give that genetic program the building blocks it needs to build a healthy body. If we give our genetic program the building blocks it needs but poison it at the same time, we should not expect good health outcomes, because these two approaches contradict each other. We cannot poison our way to health.
Authors of published studies have suggested several possibilities to explain the correlation of ALA with prostate cancer. These include:
- Oxidation products of ALA formed during cooking of meat;
- Damage done to ALA molecules during processing;
- Low ratio of LA: ALA (too little LA, which leads to breakdown of immune system function and therefore to increased cancer growth;
- Lack of balancing molecules such as phytosterols and antioxidants, which are found in seeds, but are removed or damaged during processing and cooking practices;
- Free radical formation from fatty acid oxidation. ALA-based free radicals (resulting from processing) that can damage genetic material (DNA) and lead to tumor formation;
- Decrease in the level of antioxidants, because they are used up to deal with ALA-based free radicals produced in the body;
- Alterations in eicosanoid synthesis;
- Changes in cell membrane composition, affecting permeability and receptor activity;
- Interference with 5-alpha-reductase activity;
EFAs may increase steroid hormone production that is important in androgen sensitive growth. (Actually, EFAs decrease steroid hormones. Apparently they make hormones work better, and therefore smaller amounts of hormones are needed to get their normal job done. I learned about the highly sensitive n-3 ALA in 1983. I have emphasized since that time that ALA should never be subjected to the destructive influences of light, oxygen, and high temperatures.
One or more of these destructive influences is involved during Commercial and home frying; Processing (deodorization) involved in the production of the cooking (RBD) oils that line the shelves of grocery, convenience, and health food stores; Hydrogenation, a process used to make margarine and shortening; and Partial hydrogenation of oils to make shelf stable convenience foods. Damage done to ALA molecules by light, air, and heat can produce highly toxic unnatural molecules
ALA forms more toxic breakdown products due to processing damage than does the n-6 EFA. Destructive processing is likely the cause of some of the changes that lead to increased prostate cancer. A more comprehensive story of how EFAs are damaged is found in the book Fats That Heal Fats That Kill.
Born in 1942, I'm in the age group of men that should pay attention to the condition of their prostate gland. I cannot give you medical advice or make decisions for you, but I can tell you what I do. I do not use, and recommend against the use of flax oil except in combination with other, n-6 richer oils. It is a great source of n-3 but a very poorly balanced oil, deficient in the equally necessary n-6.
I abhor the use of plastics for packaging liquids (water, oil, milk, juices, alcohol, tinctures, etc.). Liquids move all the time, and continually wash the inside of their container. You can taste plastic in water. You won't likely taste plastic in oils, but they are even more likely to drift into oils than into water, because oils swell plastics.
I do use and recommend an oil blend containing flax with sunflower and sesame oils from organically grown seeds, made with health in mind, and in the right n-3: n-6 ratio to prevent n-6 deficiency. I do insist that my oil blend is packed in brown glass and further protected by a box to keep out all light.
I also use and recommend zinc, antioxidants, phytosterols, saw palmetto, broccoli and other cruciferous vegetables, anti-inflammatory herbs, and maitake extracts or mushrooms as part of a prostate nourishing nutritional program. I use and recommend optimum intake of all components of health: 20 minerals, 13 vitamins, 8-11 amino acids, and 2 fatty acids; detoxifying fiber, digestive enzymes, and friendly bowel microorganisms; antioxidants; herbs (phytonutrients); filtered water; clean air; sunlight; and fuel.
I engage in and recommend physical activity (work or exercise) to stay fit. I indulge myself in and recommend rest; recreation; the passionate pursuit of worthwhile goals; time spent with friends; a sense of humor; good balance between work and play; heart-felt gratitude; and faith in the grand scheme of things.
I don't worry about ALA causing me prostate cancer. I use ALA on a daily basis, balanced with LA in my oil blend, as part of my program for health, along with lots of fresh organic green foods, proteins, support for digestion, and carbohydrate intake limited to the amount I burn. ALA, after all, is essential for life and for health.
Quark Information: Natural News 10/10/2010 - Quark Is Not Cottage Cheese