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Essential Fatty Acids. EFA and Omega
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.
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.
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.
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