Fatty Acids and Fish Oil

From the library of DrFuhrman.com:

Food sources of omega-3 fats.


The American diet is unquestionably low in Omega-3 fat and too high in Omega-6 fat.

Omega 3 fats are healthy fats that reduce inflammation, inhibit cancer development and protect our blood vessels. The basic building block of omega-3 fat is alpha-linolenic acid (ALA). ALA can be found in most nuts and seeds, but are particularly rich in flaxseeds, hempseeds, walnuts and leafy green vegetables. Most people do not get enough (ALA) in their diet.

Flaxseeds and hempseeds are the foods with the highest concentration of this much-needed fat. Besides omega-3 fats, these seeds also contain very high levels of photochemicals, anti-oxidents and fibers that have been shown to have beneficial effects that inhibit prostate, breast and colon cancer. However, these protective nutrients and cancer-fighting lignans are not present in significant quantity in the oil, only in the whole seed.

The whole seeds are tiny and difficult to chew, if ingested whole they typically pass through the body undigested, causing their beneficial nutrients to be lost. Therefore, it is best to buy ground flax or hemp seeds or grind the whole seeds before eating. Ground seeds are also susceptible to rancidity. In my house, we grind a pound at a time using our VitaMix and then store the ground seeds in the freezer to maintain stability of the fats until use. Every morning we just scoop what we need out of the container and put the rest back into the freezer. If you are buying ground seeds, once you open the vacuum sealed package, store it in the freezer. Flax seeds or hemp seeds can also be ground in an inexpensive coffee grinder.

The short-chain Omega-3 fats found in seeds, nuts and greens are the building block of the longer chain fat DHA, that our body needs for proper functioning of our brain, nervous system, and immune system. Besides our own production, DHA is also found in fish and fish oil.

EPA and DHA are highly beneficial.

Proponents of fish have long touted the benefits of docoshexanoic acid (DHA), an omega-3 fatty acid shown to exert significant health benefits. DHA has been shown to protect against dementia, depression, inflammatory diseases and have benefits for the heart, including anti-arrhythmic effects.

Low DHA levels are associated with:
  • Heart Disease
  • Depression
  • Schizophrenia
  • Cancer
  • Anxiety/Panic
  • Alzheimer's disease
  • Hyperactivity
  • Attention Deficit Disorder
  • Dyslexia
  • Allergies
  • Autoimmune Illnesses
  • Dermatologic Disorders
  • Inflammatory Bowel Disease
Scientists have known for many years that humans can convert short-chain omega-3 fat (ALA) from seeds and greens into the valuable DHA. The question is can we achieve optimal levels without the consumption of fish?

Studies show that people have varying ability to convert ALA into DHA, and apparently the answer is that some people eating sufficient ALA from greens, flax and walnuts can achieve adequate levels and others, even if careful to consume more ALA cannot. Conversion of ALA by the body to these more active longer-chain metabolites is inefficient: < 5-10% for EPA and 2-5% for DHA1. Men generally convert less than women.

The less fish eaten the more reliant on this conversion and the higher levels of ALA (short-chain fat) is required to produce sufficient levels of DHA. Thus, the total n-3 requirements are higher for vegetarians and those who do not eat any fish.

Because of the higher Omega-3 fat requirement for vegetarians and those not eating much fish, nutritional advisors typically encourages the consume high amounts of flax seed oil to permit the conversion of enough DHA. I do not agree with this advice. First of all oil is empty calorie food with little or no vitamins, minerals, phytochemicals and flavonoids that were present in the original seeds. To encourage health seekers to consume three tablespoons of flax oil a day is adding 360 low nutrient calories to your daily diet. Furthermore we have a significant collection of data that indicates that the consumption of high doses of ALA from flax oil may increase, not decrease the risk of prostate cancer2. Whereas flax seed consumption has been shown in multiple studies to lower the risk of both breast cancer and prostate cancer3; in contrast, flax oil and high ALA consumption has been linked to increased risk.

Should we consume fish and/or fish oil?

The amount of DHA can vary significantly in various fish. Some salmon (especially farm raised) has very little DHA, for example. More importantly, several studies have indicated that both fish and fish oil supplements are prone to contamination with toxic materials. For example fish and fish oils have been shown to contain large concentrations of dioxins and PCBs because the dumping of toxic waste and raw sewage into our oceans has taken a toll. Lipid peroxide contamination occurring with aging of the oil further complicates the supposed health benefits of fish oil consumption. Fish and fish oils also contains mercury. Data from the Center for Disease Control indicates that one in 12 women of childbearing age in the United States has unsafe mercury levels, and their threshold for safety is high. The major contributor to body mercury load is fish and fish oils, not dental fillings. Multiple studies have illustrated most of the body's mercury load is from the consumption of fish.

In spite of the toxicity and risk of consuming fish, most health authorities still advise the regular consumption of fish. This is because they consider the health benefits demonstrated from an avalanche of scientific studies showing benefits from DHA on the prevention of various diseases, including cancer and heart disease.

Not all the studies on people who consume more fish are favorable. Mercury levels from consuming fish have been linked with infertility, neurologic and mental disorders, high blood pressure, and endocrine disorders. Mercury levels from fish consumption have also been directly linked to the risk of heart attack. In an international case controlled study, mercury levels were assessed in 684 European men within 24 hours of a first myocardial infarction and in 724 control subjects without a heart attack. A strong dose response pattern was observed with a more than doubling of the risk for heart attack patients in the highest fifth of mercury levels compared to the lowest. Mercury containing fish and fish oil is obviously not the ideal way to decrease ones risk of heart attack. So epidemiologic data on fish intake and fish-oil consumption is contradictory and inconsistent; with some studies showing a worsening of cardiac events that increase as fish consumption increases.

Given the contamination issues with both fish and fish oils and the rancidity of fish oil we cannot consider fish or fish oils, health food. The studies showing an anti-cancer benefit from consuming fish are marred by other studies showing an increased risk of cancer, such as cancer of the breast from eating more fish4. This referenced study was huge and compelling; they followed over 23,000 women and found a doubling of breast cancer in women eating more fish compared to those consuming little or no fish. These inconsistencies and the data linking fish consumption to breast cancer is explained by the pollution in fish and some populations obviously consume more polluted fish than others.

DHA is definitely a beneficial fat, but we have to reconsider the source of how we find it. Fish are highly polluted, compared to other foods. We have to seriously take a closer look at the typical recommendations of health authorities to consume more fish. After many years of reviewing the evidence and recording mercury levels in patients that invariably correlate well with their fish consumption, I recommend consuming little or no fish and advice strongly against consuming any of those species of fish notoriously high in mercury such as shark, swordfish, mackerel, pike and bluefish.

If you avoid fish and instead consume fish oil, you may still have a problem. One problem with fish oils is that much of the fat has already turned rancid. If you have ever cut open a capsule and tasted it, you will find it can taste like gasoline. Many people complain of burping, indigestion and of fish breath. I have also observed that rancidity of this fish fat places a stress on the liver. Patients of mine with abnormal liver function noted on their blood tests when consuming fish oil have had these tests return to normal when the fish oils were stopped.

Searching for a healthful alternatives to fish oil.

When I draw blood tests for fatty acid analysis on many of my patients, I find that a large percentage of individuals who do not eat fish regularly do not have optimal levels of DHA. I often see patients eating otherwise excellent diets with itchy dry skin, seborrheac dermatitis and other signs of DHA deficiency. How can we assure optimal production of DHA fat for all, if we are hesitant about recommending and consuming fish or refined oils?

Fortunately, vegetable derived DHA is an alternative. Laboratory cultivated DHA is made from micro-algae and is a pure form of DHA without rancidity. It is grown in the laboratory, not collected in the wild. It has no mercury or other toxins.

Even algae-derived DHA can develop rancidity. Over the last few years, I have worked with a manufacturer to eliminate rancidity and, improve taste and digestibility of these oils. Out of necessity for my patients, I made DHA derived from freeze dried algae to preserve freshness.

Dr. Fuhrman's DHA Purity contains 30 ml of pure, all vegan, DHA concentrated liquid. The DHA comes from algae grown under sanitary laboratory conditions. In conjunction with a high nutrient, plant-based diet, I advise all people take one of these supplements daily.

Other Supplement Recommendations:
  1. My recommendations regarding nutritional supplementation are clear and simple:
  2. Take one tablespoon of ground flax seeds per day
  3. Take 0.5 ml DHA Purity liquid per day
  4. Take two Dr. Fuhrman's Gentle Care Formula per day
This keeps the supplemental recommendations simple and inexpensive for most of my patients who follow my Eat To Live plan. One bottle of my Gentle Care Formula lasts 3 months, and one bottle of my DHA Purity lasts 2 months. This is a small price to pay for health security assuring all your nutritional bases are covered from minimal supplementation. 1. Davis, B. C. and P. M. Kris-Etherton. Achieving optimal essential fatty acid status in vegetarians: current knowledge and practical implications. Am J Clin Nutr 2003;78(3 Suppl):640S-646S. Brenna, J. T. Efficiency of conversion of alpha-linolenic acid to long chain n-3 fatty acids in man. Curr Opin Clin Nutr Metab Care 2002;5(2):127-32.

2. Brouwer IA, Katan MB, Zock PL. Dietary alpha-linolenic acid is associated with reduced risk of fatal coronary heart disease, but increased prostate cancer risk: a meta-analysis. J Nutr 2004 Apr;134(4):919-22

3. Demark-Wahnefried W, Price DT, Polascik TJ, et al. Pilot study of dietary fat restriction and flaxseed supplementation in men with prostate cancer before surgery: exploring the effects on hormonal levels, prostate-specific antigen, and histopathologic features Urology 2001 Jul;58(1):47-52.

4. Stripp C, Overvad K, Christensen J, et al. Fish intake is positively associated with breast cancer incidence rate. J Nutr 2003;133(11):3664-9.
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Comments (2) Read through and enter the discussion with the form at the end
Kyle Key - May 16, 2007 10:15 AM

More people should read this article; the nutrition mainstream discusses DHA as if fish were the only source...without ever wondering, where do the fish get this DHA? Plants, of course.

Darrell Williams - May 16, 2007 10:48 AM

Flax seed coffee grinder trick to make for easy grinding and cleanup. Mix one part of oat bran with 5 parts of flax seed and place in freezer before grinding. Grind in batches and store in freezer. One HEAPING TBS of mix, then, provides one TBS flax plus a bit more fiber from the bran.

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