Disclaimer: This information is for educational purposes only, and does not replace individualized diagnosis and care.
Healthy Fats Essential Fatty Acids
The following article started as a class handout for a vegetarian cooking class where I was the guest speaker in 2001. Since then, this page has become immensely popular on the internet, probably because of its practical
cooking tips on including Omega-3 in the diet. Most Americans are Omega-3 deficient because of our over-processed diets, and one of the most common symptoms of Omega-3 deficiency is depression, among other mental health symptoms. Of course depression is common among Americans. Is this why so many people
take St. John's Wort, Prozac, Ritalin, even drink coffee? Could it be a simple deficiency? There are other causes of depression, for example mercury poisoning is the reason behind dentists' higher suicide rate, but I think most
depression in America is Omega-3 deficiency based.
Essential Fatty Acids are the "good fats" all over the news these days, and a very hot research topic. More is known about them every week as more studies come forward. Some information hasn't changed since Julius Fast wrote his book The Omega-3 Breakthrough (Tucson, Arizona: The Body Press 1987, ISBN 0-89586-625-0). For example, good fats compete with bad fats, so it's important to minimize the intake of trans fats and cholesterol (animal fat) while consuming enough good fats. Also, good fats raise your HDL or "good cholesterol". One of the jobs of this High Density Lipoprotein (HDL) or "good cholesterol" is to grab your bad cholesterol, LDL (Low Density Lipoprotein), and escort it to the liver where it is broken down and excreted. In other words, these good fats attack some of the damage already done by the bad fats. This is very important in an age when so many Americans are struggling to get their cholesterol down, and fight heart disease and obesity.
Essential Fatty Acids (EFAs)
• Essential Fatty Acids (EFAs) are necessary fats that humans cannot synthesize, and must be obtained through diet. EFAs are long-chain polyunsaturated fatty acids derived from linolenic, linoleic, and oleic acids. There are two families of EFAs: Omega-3 and Omega-6. Omega-9 is necessary yet "non-essential" because the body can manufacture a modest amount on its own, provided essential EFAs are present. The number following "Omega-" represents the position of the first double bond, counting from the terminal methyl group on the molecule. Omega-3 fatty acids are derived from Linolenic Acid, Omega-6 from Linoleic Acid, and Omega-9 from Oleic Acid.
• EFAs support the cardiovascular, reproductive, immune, and nervous systems. The human body needs EFAs to manufacture and repair cell membranes, enabling the cells to obtain optimum nutrition and expel harmful waste products. A primary function of EFAs is the production of prostaglandins, which regulate body functions such as heart rate, blood pressure, blood clotting, fertility, conception, and play a role in immune function by regulating inflammation and encouraging the body to fight infection. Essential Fatty Acids are also needed for proper growth in children, particularly for neural development and maturation of sensory systems, with male children having higher needs than females. Fetuses and breast-fed infants also require an adequate supply of EFAs through the mother's dietary intake.
• EFA deficiency is common in the United States, particularly Omega-3 deficiency. An ideal intake ratio of Omega-6 to Omega-3 fatty acids is between 1:1 and 4:1, with most Americans only obtaining a ratio between 10:1 and 25:1. The minimum healthy intake for both linolenic (Omega-3) and linoleic (Omega-6) acid via diet, per adult per day, is 1.5 grams of each. One tablespoon of flaxseed oil can provide this amount, or larger amounts of other linolenic-rich foods. Because high heat destroys linolenic acid, cooking in linolenic-rich oils or eating cooked linolenic-rich fish is unlikely to provide a sufficient amount.
• EFA deficiency and Omega 6/3 imbalance is linked with serious health conditions, such as heart attacks, cancer, insulin resistance, asthma, lupus, schizophrenia, depression, postpartum depression, accelerated aging, stroke, obesity, diabetes, arthritis, ADHD, and Alzheimer's Disease, among others.
Omega-3 (Linolenic Acid)
• Alpha Linolenic Acid (ALA) is the principal Omega-3 fatty acid, which a healthy human will convert into eicosapentaenoic acid (EPA), and later into docosahexaenoic acid (DHA). EPA and the GLA synthesized from linoleic (Omega-6) acid are later converted into hormone-like compounds known as eicosanoids, which aid in many bodily functions including vital organ function and intracellular activity.
• Omega-3s are used in the formation of cell walls, making them supple and flexible, and improving circulation and oxygen uptake with proper red blood cell flexibility and function.
• Omega-3 deficiencies are linked to decreased memory and mental abilities, tingling sensation of the nerves, poor vision, increased tendency to form blood clots, diminished immune function, increased triglycerides and "bad" cholesterol (LDL) levels, impaired membrane function, hypertension, irregular heart beat, learning disorders, menopausal discomfort, itchiness on the front of the lower leg(s), and growth retardation in infants, children, and pregnant women.
Found in foods:
• Flaxseed oil (flaxseed oil has the highest linolenic content of any food), flaxseeds, flaxseed meal, hempseed oil, hempseeds, walnuts, pumpkin seeds, Brazil nuts, sesame seeds, avocados, some dark leafy green vegetables (kale, spinach, purslane, mustard greens, collards, etc.), canola oil (cold-pressed and unrefined), soybean oil, wheat germ oil, salmon, mackerel, sardines, anchovies, albacore tuna, and others.
• One tablespoon per day of flaxseed oil should provide the recommended daily adult portion of linolenic acid, although "time-released" effects of consuming nuts and other linolenic-rich foods is being studied, and considered more beneficial than a once-daily oil intake.
• Flaxseed oil used for dietary supplementation should be kept in the refrigerator or freezer, and purchased from a supplier who refrigerates the liquid as well.
• Canola oil is often used as a cheaper alternative to the healthier virgin olive and grapeseed oils. Although Canola has at least some linolenic content, supermarket varieties of canola oil are often refined and processed with chemicals and heat, which destroy much of its linolenic acid. Cold-pressed, unrefined Canola oil is a healthier type of Canola (sometimes pricier than virgin olive oil), and found primarily in health food stores and specialty markets. The word "canola" is derived from "Canadian oil", as Canola was developed in Canada from the rape plant. Rape is a plant in the mustard family, and its rapeseed oil has at times been illegally blended with olive oil, particularly in Europe, to cheapen olive oil production costs. Although rapeseed oil is high in linolenic acid, it can make humans seriously ill if enough is consumed, and olive oil cheapened with rapeseed oil has a history of severely sickening its consumers. (Every feel itchy after eating commercial brands of peanut butter? Check the label -- it probably contains rapeseed oil.) Canola was developed to eliminate chemicals toxic to humans in rapeseed oil, thus creating an inexpensive oil with linolenic acid. Unlike olive and flaxseed oil, both known to the ancients and used as mankind evolved, Canola is a recent oil, and its long-term effects on humans are not yet known.
• Unripe flaxseeds contain a natural form of cyanide, and home gardeners should be cautious if trying to grow flax. The seeds must be ripe before harvesting. If attempting to grow flax at home, consult an experienced grower.
Omega-6 (Linoleic Acid)
• Linoleic Acid is the primary Omega-6 fatty acid. A healthy human with good nutrition will convert linoleic acid into gamma linolenic acid (GLA), which will later by synthesized, with EPA from the Omega-3 group, into eicosanoids.
• Some Omega-6s improve diabetic neuropathy, rheumatoid arthritis, PMS, skin disorders (e.g. psoriasis and eczema), and aid in cancer treatment.
• Although most Americans obtain an excess of linoleic acid, often it is not converted to GLA because of metabolic problems caused by diets rich in sugar, alcohol, or trans fats from processed foods, as well as smoking, pollution, stress, aging, viral infections, and other illnesses such as diabetes. It is best to eliminate these factors when possible, but some prefer to supplement with GLA-rich foods such as borage oil, black currant seed oil, or evening primrose oil.
Found in foods:
• Flaxseed oil, flaxseeds, flaxseed meal, hempseed oil, hempseeds, grapeseed oil, pumpkin seeds, pine nuts, pistachio nuts, sunflower seeds (raw), olive oil, olives, borage oil, evening primrose oil, black currant seed oil, chestnut oil, chicken, among many others.
• Avoid refined and hydrogenated versions of these foods.
• Corn, safflower, sunflower, soybean, and cottonseed oils are also sources of linoleic acid, but are refined and may be nutrient-deficient as sold in stores.
Omega-9 (Oleic Acid)
• Essential but technically not an EFA, because the human body can manufacture a limited amount, provided essential EFAs are present.
• Monounsaturated oleic acid lowers heart attack risk and arteriosclerosis, and aids in cancer prevention.
Found in foods:
• Olive oil (extra virgin or virgin), olives, avocados, almonds, peanuts, sesame oil, pecans, pistachio nuts, cashews, hazelnuts, macadamia nuts, etc.
• One to two tablespoons of extra virgin or virgin olive oil per day should provide sufficient oleic acid for adults. However, the "time-released" effects of obtaining these nutrients from nuts and other whole foods is thought to be more beneficial than consuming the entire daily amount via a single oil dose.
• High heat, light, and oxygen destroy EFAs, so when consuming foods for their EFA content, try to avoid cooked or heated forms. For example, raw nuts are a better source than roasted nuts. Don't use flaxseed oil for cooking, and never re-use any type of oil.
• Replace hydrogenated fats (like margarine), cholesterol-based fats (butter/dairy products), and poly-saturated fats (common cooking oils) with healthy EFA-based fats when possible. For example, instead of margarine or butter on your warm (not hot) vegetables, use flaxseed and/or extra virgin olive oils with salt. (This tastes similar to margarine, as margarine is just hydrogenated oil with salt.)
• Sprinkling flaxseed meal on vegetables adds a slightly nutty taste. Whole flaxseeds are usually passed through the intestine, absorbing water only and not yielding much oil. Also, it's best not to use huge amounts of flaxseed in its meal (ground seed) form, as it contains phytoestrogens. The oil is much lower in phytoestrogens.
• In many recipes calling for vegetable shortening, replacing the shortening with half as much virgin olive oil, and a very small pinch of extra salt, often yields similar results.
• Adding flaxseed and/or virgin olive oil to salads instead of supermarket salad oil is another healthy change.
• Replace oily snack foods, like potato chips and corn chips, with nuts and seeds.
• Extra virgin olive oil or grapeseed oil are best to use for cooking oil, as they withstand high heat well.
I have received a number of thoughtful e-mails from people, one asking the difference between http://www.udoerasmus.com/ Udo's Ultimate Blend as a supplement and plain flaxseed oil. (There are many other good blended oil products on the market, but Udo's is one of the most popular.) I think the answer is important enough to repeat here. Flaxseed oil is the highest Omega-3 food known, with only one tablespoon per day providing enough Omega-3 fatty acids for a slightly overweight adult. Most Americans get plenty of Omega-6 fatty acid, the other essential fatty acid that the body can't manufacture on its own, but often this is of low quality, for example from food cooked in vegetable oil. From Omega-3 and Omega-6 fatty acids, the body manufactures other fats and compounds such as Omega-9, EPA, and DHA (the animal form of Omega-3 found in certain fish oils). Some people with health problems such as diabetes, poor diets, a smoking or alcohol addiction, and so forth, have trouble making their own compounds from the two essential fatty acids. Udo's oil is a blend of healthy oil which provides quality Omega-3, Omega-6, and Omega-9 fatty acids in a ratio considered ideal. The oil, like Barlean's flaxseed oil, is made from cold-pressed organic oils.
The two types of oil have their own advantages. For people with poor diets or diets poor in healthy oils, or with added health problems, the advantage to Udo's is that a person obtains the right ratio of oils. The advantage to flaxseed oil is cost. If a person is consuming good quality Omega-6 in the diet (and possibly Omega-9 as well, from foods like olive oil or almonds), then taking 1 tablespoon per day of flaxseed oil is cheaper than 2-3 tablespoons of Udo's oil for the same body weight. A person could also blend their own organic olive oil with flaxseed oil for a slightly less expensive option. Both types of oil require refrigeration. I don't sell or endorse any product on this page (other than my cookbook, of course), and so I'll leave oil choice up to my readers.
Quantification of oil in natural foods
Several other readers have written asking why I don't include quantities of oil for each of the natural foods containing EFAs. This is largely because the different charts I've found with oil amounts vary widely. The sources are all reputable, however their laboratory findings are different. This could be due to a natural fluctuation in the type of food analyzed, or from differing laboratory technique. A couple of readers have complained that foods like
avocados, sesame seeds, Brazil nuts (although rich in natural minerals), or chestnuts don't contain large quantities of essential oils, possibly not enough for a person to obtain everything he or she needs in smaller portions. I don't make claims concerning the amount needed for each food, because I don't feel that
I have a reliable source to provide this information. Obviously, many people choose to supplement because they can be sure of getting enough. And so I leave it up to the reader to determine whether supplementation is needed in addition to the foods in his or her diet.
Others have questioned the amount needed by children. I haven't been able to
research this specific topic yet, and recommend that people research it on their own. A pharmacist gave me his opinion on this several years ago, saying that an infant's dose is generally 1/3 the adult dosage for most supplements, and that the dose increases for children with body weight, being equal to the adult dosage when they reach an adult-comparable body weight (usually in teenage years). I would suspect that infants and children need a good amount of Essential Fatty Acids because of their extra growth and development needs.
Flax oils vs. fish oil
In his book, Dr. Rudin (see below) points out that most Omega-3 studies are
based on fish oil. Rudin finds this disappointing, as he has had better results
with flaxseed oil in his own studies. This may be because flaxseed oil starts with the plant form of linolenic acid, ALA (alpha linolenic acid), whereas fish oil contains the animal form, DHA (docosahexaenoic acid). The body makes its own DHA and EPA (eicosapentaenoic acid) from ALA. Although some claim that the amount of DHA made is small, the body doesn't need much DHA. Most DHA is contained in cell membranes, and is held there with little replacement. In contrast, ALA and compounds made from it are also needed in the body for a number of essential functions. Fish oil cannot provide ALA, and therefore deprives the consumer of this critical compound. Some people feel that they need DHA or EPA as a supplement, and that's their personal choice. However, most sources covering the different types of oil indicate that plant-based Omega-3s, or ALA, is the better choice.
Although this article was drawn from many more sources than these two books, for readers wanting to learn more on the subject, I suggest:
Donald Rudin, MD, and Clara Felix. Omega-3 Oils; A practical Guide. US: Avery, 1996.
Andrew L. Stoll, MD. The Omega-3 Connection. New York: Fireside, 2001.
Both of these books are widely available, under $20 in paperback, and both Rudin and Stoll are Harvard-educated MDs. Stoll's book relies more on fish oil studies than Rudin's.