Do You Need to Supplement With EPA and DHA If You Follow a Whole Food Plant-Based Lifestyle?

If you bring up the subject of supplementation with a group of whole food plant-based (WFPB) advocates, it’s almost guaranteed to ignite a lively debate. In an earlier article, I wrote that supplementing with vitamin B-12 is necessary for anyone following a 100% plant-based diet and that I am not convinced that supplementing with anything else is necessary in the absence of a known deficiency.

Some WFPB advocates believe that people following a 100% plant-based diet should have some concern about the following nutrients (in addition to vit B-12)

• Vitamin D
• Calcium
• Iodine
• Iron
• Protein (for athletes)
• Eicospentenoic Acid (EPA) and Docosahexananoic Acid (DHA)

Out of all the nutrients listed above, EPA and DHA probably provoke the most discussion as far as the need for supplementation is concerned.

EPA and DHA are long chain omega 3 fatty acids. Fatty fish are good sources of both. The Mayo Clinic recommends consuming fatty fish one to two times per week for heart health. It is believed that EPA, DHA and other components are responsible for the health benefits from fish. Apparently this level of fish consumption provides health benefits that offset potential adverse effects of exposure to PCBs, methyl mercury and other contaminants found in fish.

Those following 100% plant-based diets who avoid fish and fish oil supplements can choose an algae-based supplement containing EPA and DHA.

Are EPA and DHA essential?

It depends who you ask.

Before we address this question, we have to discuss the two fatty acids that we know are essential to the human diet. First there is linoleic acid (LA) which is the most common omega 6 fatty acid. The second is alpha-linolenic acid (ALA) which is an omega 3 fatty acid. We must obtain LA and ALA in the diet because the human body cannot synthesize them.

LA and ALA serve at least three important functions:

• They assist in the formation of cell membranes,
• They are involved in the transport and oxidation of cholesterol,
• They are involved in specialized hormone production

Humans can synthesize the longer chained omega 6 fatty acid, arachidonic acid (AA) from LA. Humans can synthesize the longer chained omega 3 fatty acids, EPA and DHA, from ALA. However, it turns out that there are a number of factors that determine how efficiently each individual person makes these conversions.

Factors affecting conversion from ALA to EPA and DHA

 According to the Linus Pauling Institute at Oregon State University, gender differences and genetic variability influence one’s ability to generate EPA and DHA.

Gender Difference

The capacity to generate DHA from ALA is higher in women than in men. Studies have shown that, in healthy young men, 8% of dietary ALA is converted to EPA and 0-4% is converted to DHA. In healthy young women, approximately 21% of dietary ALA is converted to EPA and 9% is converted to DHA.

Genetic Difference

 There are strong associations between variants in human genes FADS1 and FADS2 and blood levels of EPA, DHA and other long-chained polyunsaturated fatty acids. Blood levels are influenced not only by diet, but to a large extent also by genetic variants common in a European population. Depending on genetic variants, requirements of dietary ALA or EPA and DHA intakes to achieve comparable biological effects may differ. Genetic variants may explain up to 30% of the variability in blood levels of omega-3 and omega-6 fatty acids among individuals

Although ALA is considered the essential omega-3 fatty acid because it cannot be synthesized by humans, evidence that human conversion of EPA and, particularly, DHA is relatively inefficient has led the Linus Pauling Institute to conclude that EPA and DHA may be considered conditionally essential fatty acids.

Another factor affecting conversion from ALA to EPA and DHA

 Amount of Linoleic Acid (LA) consumed

The Food and Nutrition Board’s Daily Reference Intake (DRI) for LA is 17 grams for adult men and 12 grams for adult women. The DRI for ALA is 1.6 grams for adult men and 1.1 grams for adult women. These combined amounts provide men 167 calories per day and women 118 calories per day.

Because LA and ALA are the only two essential fatty acids required by humans, you can see that our daily requirement for fat as a percentage of total calorie intake is well below 10%. Based on the DRIs, the recommended LA:ALA ratio is approximately 11:1. It has been estimated that the typical American diet provides an LA:ALA ratio of 15–17:1

Research has shown that an LA:ALA ratio of 11:1 may too high as a ratio of 4:1 or lower was shown to optimize ALA’s ability to elongate to EPA. A ratio of 4:1 down to 1:1 has also been shown to reduce risks for various chronic diseases such as cardiovascular disease, colorectal cancer, breast cancer, rheumatoid arthritis and asthma.

Not everyone agrees that the LA:ALA ratio matters much. Walter Willett and Darius Mozaffarian from Harvard and Alice Lichtenstein from Tufts University are not convinced that there is enough evidence to warrant concern about the LA:ALA ratio. They recommend replacing saturated fat in the diet with linoleic acid and other omega 6 fatty acids without worrying about the LA:ALA ratio

Christopher Ramsden, a respected fatty acid researcher, does not agree that the LA:ALA ratio is meaningless and states that much of the research on which Willett and colleagues base their conclusion is flawed.

We clearly have a lot more to learn about the ideal ratio of LA to ALA. However, if Americans reduced both saturated fats and LA in their diets, I’m confident it would result in a reduction of chronic disease..

What Foods Contain LA?

 Many plant and animal foods contain LA. The high amount of LA in the typical American diet is likely due to the high consumption of vegetable oils, animal foods and processed foods. Americans eat far too much total fat, saturated fat and LA.

Diets dominated by fruits, vegetables, whole grains and legumes (beans, peas and lentils) can easily provide 300 to 400% of the adequate intake of LA. The typical American is probably getting over 1000% of his/her daily LA needs. We’d be better off getting our LA from whole plant foods only. This would greatly reduce our LA intake.

How can we ensure we get enough ALA?

Eat your leafy greens – Certain green vegetables such as spinach, kale, brussell sprouts and purslane offer useful amounts of ALA. These foods are also nutrient dense powerhouses.

Flax and other seeds – Flax seed is the richest source of naturally occurring ALA. One tablespoon of the seeds provides approximately 2.2 grams, It’s important to ground your flax seed, otherwise it will not be absorbed very well. Ground flax seed is easily added to baked goods, cereals and other foods. Chia and hemp seeds also contain ALA, but do not need to be ground.

Nuts – The best choices here are English Walnuts and Macadamia Nuts.

Most of us will probably get enough ALA just by eating a varied WFPB diet. But if you want to play it safe, add 1 tablespoon of ground flax seed to your diet. That alone will allow you to meet your DRI of ALA.

Whatever you do, don’t try to get your ALA from extracted oils.

All oils are junk food – even olive oil.

Jenny A. Fleming and Penny M. Kris-Etrherton conducted a review of the research and concluded that there is evidence demonstrating a beneficial role of ALA for the primary and secondary prevention of Cardiovascular Disease. A similar conclusion was reached by Mozaffarian who recommended that ALA intake be increased to 2–3 g/d to reduce risk of CVD. Fleming and Kris-Etherton suggest there may be comparable CVD benefits for ALA vs EPA + DHA. However, they state that there is lack of sufficient evidence from well-controlled clinical trials on the effects of ALA on CVD risk, and consequently, establishing a recommended amount will require additional research. They propose that clinical trials be conducted to evaluate the quantitative effects of ALA intake on CVD risk to help establish a recommended amount of dietary ALA. There is a chance that their conclusion is biased as Kris-Etherton serves on the Advisory Board of The California Walnut Commission.

 Do we need to supplement with EPA or DHA?

As mentioned earlier, the Linus Pauling Institute considers EPA and DHA conditionally essential fatty acids. It recommends consuming two servings of oily fish two times per week. As you might imagine, most whole food plant based health care professionals do not concur.   One notable exception is Dean Ornish MD. He encourages patients to either consume some fatty fish or take fish oil supplements. For patients who avoid animal products, he encourages algae-based EPA and DHA supplements or supplementing with flax seed oil.

Ailsa A Welch and colleagues conducted a study and concluded that the bodies of vegans and vegetarians can respond to a lack of dietary EPA and DHA by increasing their ability to make them from ALA. So perhaps supplementing with EPA and DHA is not necessary.

However, Norman Salem Jr. and Connye N Kuratko, in a letter to the American Journal of Clinical Nutrition, question the authors’ conclusions claiming fundamental problems with the study. Salem Jr. and Kuratko happen to be employees of Martek Biosciences, a company that sells supplements that include DHA supplements derived from algae. This does not mean their objections are incorrect, but their connection with a supplement company is worth mentioning.

Are You Confused Yet?

As I’ve mentioned in previous articles, the highly reductionist mindset of nutrition researchers. (the focus on details out of context from the whole of which they are a part) will always result in confusion and controversy. It’s extremely hard to imagine that we will ever know the ideal amount of ALA, EPA, DHA, or any other nutrient for that matter, that individuals should consume.

How Do We Check to See if Blood Levels of EPA and DHA Are Adequate?

The Omega 3 Index – is red blood cell (EPA) and (DHA) expressed as weight percentage of total fatty acids (FA). According to OmegaQuant, an Omega 3 –Index testing company :

“The target Omega-3 Index is 8% and above, a level that current research indicates is associated with the lowest risk* for death from CHD. This is also a typical level in Japan, a country with one of the lowest rates of sudden cardiac death in the world. On the other hand, an Index of 4% or less (which is common in the US) indicates the highest risk*. At present, there is no reason to suggest that the target should be different for men vs. women, or for different age groups. Whether there is an upper limit of safety for the Index is not clear, but there is likely a value above which there is not likely to be any additional health benefit. Further research will help define this level.

*In this context, “risk” refers only to that associated with differing levels of omega-3 fatty acids. Risks associated with other factors such as cholesterol, blood pressure, diabetes, family history of CHD, smoking, or other cardiac conditions are completely independent of the Omega-3 Index. All risk factors – including the Omega-3 Index—should be addressed as part of any global risk reduction strategy.”

The bolding of the last sentence is mine. The Omega-3 index has to be considered among a myriad of cardiac risk factors. The big danger I see is how someone may get a false sense of security if he discovers that his Omega-3 Index is 8% or above. The typical American has many other risk factors such as high blood pressure,   obesity, poor diet, high total serum cholesterol, and high LDL cholesterol among others.

Will taking an EPA + DHA supplement guarantee levels above 8%?

Not according to OmegaQuant:

“No. There is no way to predict – for any given person – what his/her Omega-3 Index will be just by knowing how much fish they eat or how many capsules they take. Individual differences in metabolism, absorption, and genetics make it impossible to predict with certainty how a given person will respond to supplements.”

So taking an EPA + DHA supplement will not guarantee that blood levels will rise to 8% of total FA.

What do Some WFPB Advocates Think?

The pro supplement camp

Joel Fuhrman MD (for supplementing)

Dr. Fuhrman has found that a large percentage of his patients do not have optimal levels of DHA, even those eating walnuts and ground flaxseeds on a regular basis. He claims that he sees non fish eating plant-based patients with itchy dry skin, seborrheic dermatitis and other signs of DHA deficiency.

Dr. Fuhrman acknowledges that some vegans and vegetarians who regularly consume walnuts and flaxseeds may produce enough EPA and DHA on their own and may not require supplementation.

On his website he writes:

“Because this issue is so imperative to their health it should be confirmed with a blood test (Omega 3 Index) before assuming that the conversion level is adequate. In order to assure optimal production of DHA and EPA, without recommending that the consumption of fish or refined fish oils, I recommend taking a vegetable-sourced DHA supplement.  DHA is the more important of the two to supplement, since more ALA can be converted to EPA than to DHA, and because DHA can be naturally retro-converted to EPA internally.  However, taking a small amount of EPA in addition will help to assure adequacy, and a vegan form of EPA is now available.”

Jack Norris RD (for supplementing)

Jack Norris states that the body can convert ALA into EPA and DHA. ALA is efficiently converted to EPA, but it may require large amounts of ALA to produce optimal amounts of DHA. A small amount of recent evidence has raised a concern that large amounts of ALA could be harmful to the eyes over the long term. Here are his recommendations for vegetarians considering supplementing with EPA and DHA.

“Without diet planning, vegans and vegetarians have low omega-3 intakes and blood levels; and in some cases, older vegans have close to no DHA in the blood. It is not clear whether these lower blood levels are harmful (and it is not likely to be well understood any time soon). Because DHA supplements are relatively expensive we suggest two options for vegetarians under Step 1.

Step 1: DHA Supplement

• Option A – If you want your DHA levels to be the same as non-vegetarians, supplementing with 300 mg per day will likely accomplish that.
• Option B – If you just want some insurance that you are getting a source of DHA in case your body isn’t efficient at making it, supplementing with 200 – 300 mg every 2-3 days will provide that.
• Vegetarians over 60 years old should err on the side of Option A.

Caution: Too much omega-3s can result in bleeding and bruising. If you have reason to believe you have problems with easy bleeding or bruising, or are already consuming plenty of omega-3s, consult a health professional before following these recommendations or adding more omega-3 to your diet.

Step 2: Minimize Omega-6 Oils

• Do not prepare food with oils high in omega-6 such as corn, soy, safflower, sunflower, most vegetable oil blends (typically labeled “vegetable oil”) and sesame oil. Instead, use low omega-6 oils like olive, avocado, peanut, or canola. Only cook canola under low heat and for short periods.

Step 3: Add some ALA

• Add 0.5 g of uncooked ALA to your diet daily. This would be the equivalent of:

1/5 oz English* walnuts (3 halves) 1/4 tsp of flaxseed oil 1 tsp of canola oil 1 tsp ground flaxseeds

*English walnuts are the typical walnuts for sale in grocery stores. They are distinct from black walnuts.”

Ginny Messina RD (for supplementing)

DHA: 200 to 300 mg several times a week. It may be a good idea, but we don’t know for sure. She takes this amount almost daily and would recommend it in particular for anyone who is prone to depression. (Low serum DHA has been associated with increased suicide risk).

Michael Greger MD (Nutritionfacts.org) (for supplementing)

In his 2015 Bestseller “How Not To Die” Dr. Greger writes that uncertainty about the body’s ability to make enough EPA and DHA for optimal brain health compels him to recommend taking 250 mg of pollutant-free EPA and DHA directly from algae.

According to Dr. Greger, algae used for supplements are grown in tanks and never come in contact with the ocean and its pollutants. He writes:

“That’s why I recommend a contaminant-free source to get the best of both worlds, omega 3 levels associated with brain preservation and minimized exposure to industrial pollutants.”

Dr. Greger and the other pro supplement campers are respected WFPB experts and they make good cases for taking an algae-based EPA and DHA supplement. However there are equally respected WFPB experts who are against supplementing with EPA and DHA.

 George Eisman M.A., M.Sc., RD (against supplementing)

 How much fat is enough?

 “The need for lipid (fat) is actually the need for essential fatty acids (EFAs) The U.S. recommendation for these has been set at 3% of calories. Since plant-derived lipids average about 1/3 EFA, this means that a diet containing 9% or more of its calories as fat will meet this recommendation {which in itself is actually very generous compared to minimal needs.) For a typical adult diet (about 2000 calories,) the equivalent of two teaspoons of corn oil will meet the 3% recommendation. The key word in the previous sentence is “equivalent” since that amount of oil is naturally present in 10 cobs of whole corn (830 calories) or in 10 slices of whole wheat bread (650 calories) In fact it is quite impossible to design a whole-foods vegan diet that wouldn’t meet this recommendation. Even fruits and vegetables average 5% of calories from EFA. Yes we need some fat in our diet; no, we don’t have to consume it as isolated oil.

 Animal fats average less than 1/10 EFA – dairy fat being NOTORIOUSLY low at 1/50. Thus just to meet EFA recommendations, someone consuming an all-animal product diet would have to increase their fat intake considerable (to at least 30%) If someone ate nothing but dairy products, she or he could not meet the recommendation at all, since 1/50 is equivalent to 2%. No matter how much was eaten, only 2% of calories would be EFA.”

John McDougall MD (against supplementing)

Dr. McDougall does not consider any extracted oil as food. He calls oils medicines at best and toxins at worst. He writes how oils function as medicine:

‘When the oils are removed from their natural environments—for example, from the seeds of corn, soybeans, safflowers, or flax, or the fruit of an olive or avocado—they are no longer a food.  Yes, they do supply concentrated calories—but the rest of the original nutrition found in the plant parts is absent.  In this state, the free oils can display powerful pharmacological effects—some beneficial and some harmful.  This would be analogous to removing vitamins and minerals from plants and making supplements.  I don’t call supplements food, do you?  However, the effects of concentrated, isolated oils are usually even more potent than those seen with supplements.”

Here are his thoughts on free oils as toxins:

“As with all other medications, there are adverse effects from consuming free oils, when added from a bottle to meals or taken as pills.  The most obvious adverse effect is people gain weight when they eat even so-called “healthy oils,” like olive oil. When 54 obese women in a Mediterranean country were studied, these women were found to be following a diet low in carbohydrates (35% of the calories) and high in fats (43% of the calories).  Of the total calories from fat, 55% came from olive oil.¹  My point: a Mediterranean diet which is loaded with olive oil, rather than fruits and vegetables, will make you fat.

Omega-3 and omega-6 oils thin the blood, which make a person more susceptible to bleeding.^2,3  This side effect from taking essential oils to prevent a heart attack could become fatal after an automobile accident or if an artery in the brain were to rupture, such as occurs in a hemorrhagic stroke.

Free oils may be toxic to the body tissues.  Both omega-3 and omega-6 fats are associated with an increased risk of opacification of the lens of the eye, resulting in cataracts.⁴

Omega-3 and omega-6 oils could benefit people with autoimmune disorders. On the other hand, excessive intake of these fats may actually aggravate these disorders.⁵  More importantly, we need our immune system functioning at full capacity to fight off infections and cancer.  Free oils have been demonstrated to suppress many natural microbe killing mechanisms (with a marked decrease in cytokine, tumor necrosis factor-alpha and interferon-gamma) ⁶   

Research on animals suggests the omega-6 variety of oils is very cancer-promoting and the omega-3 variety may be beneficial for cancer prevention.⁷  However, this may not be the case.  In one animal experiment on colon cancer, a fish oil diet and a safflower oil diet induced, respectively, 10- and 4-fold more metastases (number) and over 1000- and 500-fold more metastases (size) than were found in the livers of rats on the low-fat diet.⁸  Other, animal experiments also have shown essential fats to be cancer promoting ^{9 10} Most importantly, population studies tell us that, worldwide, the lower the total fat intake, the less the risk of common cancers, such as breast, colon and prostate.”

Dr. McDougall believes the current research shows the human body has no difficulty converting the plant-derived omega-3 fat, ALA, into DHA or other omega-3 fatty acids, in the liver, thus supplying our needs even during gestation and infancy.

Dr. McDougall cites a study published in 2009 in the journal “Prostaglandins Leukotrienes and Essential Fatty Acids” whose main author concluded that:

“In the absence of convincing evidence for the deleterious effects resulting from the lack of DHA from the diet of vegetarians, it must be concluded that needs for omega-3 fatty acids can be met by dietary ALA (alpha linolenic acid).”^11”

T. Colin Campbell PhD (against supplementing)

In an article originally written in Dec. 2009 and modified in November, 2015, T, Colin Campbell addressed the question of whether a DHA supplement was necessary when following a 100% plant based diet.. Here is part of his response:

“If I must answer the DHA question, I would only say that we can get plenty of that type of chemical from the consumption of the omega-3 fatty acids that are found in certain plants–certain nuts, flaxseed, etc. Indeed, it also is related to a dietary balance of omega-3 to omega-6 fatty acids and this balance can be readily met with a good quality diet of wholesome vegetables, fruits, grains and nuts.”

Jeff Novick RD

Jeff Novick believes that advocates for supplementing with EPA and DHA have been too quick to dismiss the DART-2 results showing increased risk in angina sufferers.

He states that other reasons for abstaining from supplementing with EPA and DHA include:

• Research on omega-3s and adult mental function favors EPA rather than DHA and a little DHA is retro-converted to EPA. ALA is effective in raising EPA levels. .
• In terms of DHA supply to nervous tissue during pregnancy, ALA reduces signs of omega-3 deficiency (e.g. elevated levels of Osbond acid) indicating that it acts as a source of DHA even if little conversion is evident in blood samples.
• The evidence of adverse effects of ALA is either sparse (eye) or contradictory (prostate)
• Reviews of omega 3 fatty acids and depression provide no basis to recommend the use of pure DHA (as per most vegan supplements) to combat depression.
• A collaborative analysis of studies comparing vegetarians with other dietary groups, including fish eaters, showed very comparable results. The fish-eaters will have had higher intakes of EPA and DHA than the vegetarians, but this does not seem to have conferred an advantage

Novick concludes that. “once again, evidence to recommend EPA/DHA seems lacking”.

 Matthew Lederman MD (against supplementation)

Dr. Lederman calls into question the conclusions of a study by Kornsteiner et al, that showed very low EPA and DHA status in Austrian vegetarians and vegans. Although the study showed that vegans had lower levels than omnivores, there was no investigation of health issues or the benefits of supplementing with EPA and DHA. The vegans in the study had a 10:1 omega 6 to Omega 3 ratio and it was clear that the vegans were not following a healthy WFPB diet.

Dr. Lederman also cites problems with another study on the maternal consumption of DHA functional food. The study tested the hypothesis that infants born to women who consumed a DHA-containing functional food during pregnancy would demonstrate better problem-solving abilities and recognition memory than would infants born to women who consumed a placebo during pregnancy. The study did show a statistically significant difference in problem-solving skills in 9 month old infants.

Important aspects of the study to consider include:

• Very small study size (30 infants)
• Clinical (real-life) significance was questionable at best
• No difference in recognition memory in infants at 9 months
• There was no significant differences between groups in any measure of Fagan Test of Infant Intelligence.

Lederman informs us that there is very little to show causal relationships of DHA intake. We have even less OUTCOMES data where we know what happens specifically due to DHA interventions without other variables confusing the picture.

There is also no evidence that everyone with low levels will get Parkinson’s nor is there evidence that everyone with low levels who takes supplements will prevent Parkinson’s or have better health.

One question Lederman asks is “who decides what blood levels of EPA and DHA are considered. normal? Normal doesn’t necessarily mean healthy. He also reminds us that there are no DHA placebo controlled intervention studies over a long period of time in large groups that show that consuming DHA in supplement form provides significantly improved health and no harm.

Summary of Dr. Lederman’s Views on EPA and DHA

 Vegans are told to take DHA and EPA supplements – THIS IS NOT NECESSARY IF YOU FOLLOW A BALANCED WFPB DIET!!!

The solution is not to add ALA, EPA and/or DHA supplements, but to eliminate all oils and limit fatty whole plant food consumption (nuts, seeds, nut butters a avocados and olives) so ALA can be effectively converted.

 The problem for most people is not a deficiency of Omega – 3, but an excess of Omega – 6.   WE SHOULD REDUCE OMEGA – 6!!

  For WFPB dieters:

•  Physicians need to tell patients what is proven vs. expert opinion
• Must show through prospective, randomized controlled studies that low-fat WFPB dieters can actually improve their health without any harm from the new recommended intervention (supplement)
• Burden of proof is high!
• Must show that there is a current problem that needs fixing – not just show different DHA levels in vegans and omnivores
• When dealing with supplements, the default recommendation should be NO supplementation – never the opposite
• Why are we in such a rush to manipulate our own biochemistry?

Note: Dr. Lederman makes clear that possible exceptions may apply to some sick WFPB dieters.

My Thoughts

 Back in 2012, I was sufficiently concerned enough to contemplate purchasing an algae based DHA supplement. Before making the purchase, I watched a lecture by Dr. Lederman and became convinced to hold off on my purchase.   My position hasn’t changed since then. I concur with Dr. Lederman when he insists that the burden of proof is high on anyone who recommends a dietary supplement in absence of deficiency symptoms.

However, if convincing evidence ends up showing that low DHA levels in vegans puts them at greater risk for Parkinson’s disease and other neurological maladies, I’ll certainly consider supplementing.

My purpose for writing this blog article was NOT to advise anyone on whether to supplement or not to supplement with EPA and DHA. The purpose was to demonstrate that the question is far from settled. I also wanted to provide sufficient information to help readers make an informed decision or to be inspired to gather additional information.

As always, I wish you great health no matter what you decide.

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3) Nordstrom DC, Honkanen VE, Nasu Y, Antila E, Friman C, Konttinen YT.  Alpha-linolenic acid in the treatment of rheumatoid arthritis. A double-blind, placebo-controlled and randomized study: flaxseed vs. safflower seed. Rheumatol Int. 1995;14(6):231-4.

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6) Purasiri P, Mckechnie A, Heys SD, Eremin O. Modulation in vitro of human natural cytotoxicity, lymphocyte proliferative response to mitogens and cytokine production by essential fatty acids. Immunology. 1997 Oct;92(2):166-72.

7) Sauer LA, Blask DE, Dauchy RT.  Dietary factors and growth and metabolism in experimental tumors.  J Nutr Biochem. 2007 Apr 4;

8) Griffini P.  Dietary omega-3 polyunsaturated fatty acids promote colon carcinoma metastasis in rat liver. Cancer Res. 1998 Aug 1;58(15):3312-9.

9) Coulombe J, Pelletier G, Tremblay P, Mercier G, Oth D.  Influence of lipid diets on the number of metastases and ganglioside content of H59 variant tumors. Clin Exp Metastasis. 1997 Jul;15(4):410-7.

10) Klieveri L. Promotion of colon cancer metastases in rat liver by fish oil diet is not due to reduced stroma formation. Clin Exp Metastasis. 2000;18(5):371-7.

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