For the most part, organisms can satisfy their own fatty acid needs. In mammals, however, those enzymes which insert double bonds into the chains of fatty acids cannot insert them into the omega-3 and omega-6 positions. Linoleic and linolenic acid contain omega-6 and 3 bonds and are necessary for mammalian metabolism. These two fatty acids are therefore essential fatty acids (EFA) and must be supplied by the diet.
Variations among species and within species occur in terms of what is or is not essential and at what levels. For example, the cat is limited in its ability to synthesize arachidonic acid (AA, 18:4w6). 1,2 Humans are unable to synthesize sufficient fatty acids with double bonds closer to the methyl end than omega-9. Varying capabilities occur even within species. 3 A diet satisfactory for one individual may not be for another, since enzyme systems regulating synthesis and metabolism vary with individual genetics.
Varying environmental circumstances may also alter needs. A sufficient diet this week may not be so next week if circumstances change. The consumption of alcohol or medications, the presence of disease, atrophy, increased stress, increased consumption of trans- fatty acids (present in all foods containing partially hydrogenated oils), dieting, obesity, allergy, young age, old age, high cholesterol, and so forth can all alter nutrient requirements. 4 There is no such thing as an average requirement which fits everyone all the time.
Some factors affect dietary intake while others affect the ability of essential fatty acids, once consumed, to convert through the steps necessary to form their physiologically important end products. For example, LA (18:2w6) consumed must first be converted to gamma linolenic acid (GLA, 18:3w6) by desaturase enzymes, and then on to other products by enzymes to form important eicosanoids such as prostaglandins. Many factors (stress, disease, allergy, etc.) can interfere with this first step mediated by delta-6-desaturase to create GLA. 5 Therefore, for some individuals, GLA or its progeny may have to be directly supplied to the diet thus by-passing the need for this enzyme. This is the rationale for the use of the supplement evening primrose oil since it contains high levels of GLA. Other oil sources such as black currant seed, borage, and fish also supply fatty acids which skip several steps in these metabolic pathways and thus may be important dietary components for some individuals (animals and people). (Fig. 13)
An important component of fish oil, for example, eicosapentaenoic acid (EPA, 20:5w3) may become a dietary essential if age or other factors limit the ability to convert dietary plant-derived LNA (l8:3w3) into EPA, which is the precursor to several important omega-3 derived eicosanoids.
Although not considered essential fatty acids in the sense of LA and LNA, there are at least four other unsaturated fatty acids in nutrition now recognized as playing key biochemical roles, and for which there may be an essential requirement for some individuals. These are oleic acid (OA, 18: 1w9), gammalinolenic acid (GLA, 18:3w6), eicosapentaenoic acid (EPA, 20:5w8), and docosahexaenoic acid (DHA, 22:6w3). This list is surely incomplete.
Note that OA is a mono-unsaturated compound (one double-bond), GLA has three double bonds, and EPA and DHA have five and six double bonds, respectively. (Fig. 5) Linolenic acid (manufactured only in plant chloroplasts) as well as EPA and DHA belong to the omega-3 family of fatty acids; LA and GLA, as well as arachidonic acid (AA: 20: 4w6), are members of the omega-6 family. Oleic acid is a member of the omega-9 family. All these fatty acids have great biochemical significance and the understanding of their metabolic roles is increasingly demonstrating their link to health and disease.
The essentiality of fatty acids, like that of all other nutrients, is linked to many variables. Required amounts and types of fatty acids can vary among species and even for the same individual. Diets rich in unaltered fatty acids (particularly raw whole foods) and specific properly prepared fatty acid supplements (a second choice) can provide sufficient fatty acid substrate for optimal health.
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Society has finally gotten over the ?fat free? craze and realized that fats are important to human development.
In fact, there are certain fats called ?Essential Fatty Acids? that play an important role in your body's functioning. These fats are so important that you should take extra steps to get them into your daily diet. These essential fats are found in polyunsaturated fats.
Essential Fatty Acids (EFAs) are necessary fats that your body can't make on its own. They must be part of your diet. You may have heard of Omega-9s. These are not ?essential? like the Omega-3 and Omega-6, and are thought of as ?good? fatty acids.
Benefits of Essential Fatty Acids
EFAs help support your cardiovascular, reproductive, immune and nervous systems. You need them to help manufacture and repair cell membranes. They help your cells get the most out of the foods that you eat and get rid of the chemicals and toxins that are in your body.
What Foods Contain Omega-3s?
Omega-3 is also known as Alpha-Linolenic Acid (LNA).
Omega-3 is found in oily fish, such as salmon, herring, sardines, trout, tuna, and rainbow trout.
Other sources include canola oil, flaxseeds, and hempseeds.
You can also find Omega-3 EFAs in dark green vegetables like broccoli, kale, seaweed and spinach.
What Foods Contain Omega-6s?
Omega-6 is also known as Linoleic Acid (LA).
Omega-6 is found in safflower oil, sunflower oil, corn oil, sesame oil, hemp oil, pumpkin oil, soybean oil and walnut oil.
Omega-6 May be in our Diets in Excess
Because so much oil is used in the North American diet ? you may have an excess of Omega-6 in your diet. The ideal ratio of EFA Omega-3 to Omega-6 is 3:1. In other words, you should have 3 times as much Omega-3 as Omega-6.
Most people actually need to reduce their Omega-6 and increase their Omega-3 intake.
In all cases, you should keep your fat (and even Essential Fatty Acids) ? to less than 25% of your daily dietary intake.
Omega-3 and Weight Loss
Omega-3 fatty acids are particularly beneficial because of the role they play in weight loss.
They help regulate your blood sugar levels, and help with cravings and excess hunger. This could contribute to lowering your risk of diabetes and obesity.
A recent study published in the International Journal of Obesity showed a link between Omega 3 fish oil and the number of calories burned in a day. The study compared the calories burned by a control group versus the calories burned by test subjects who received 1.8 grams of fish oil supplements per day.
The results showed that the test group burned 26% more calories each day. The researchers also found that the group that took the supplements experienced 50% lower insulin levels. Not only were they burning more calories, but also their bodies were producing less fat due to the fish oil. Insulin increases the activity of enzymes that store fat. Less insulin means less fat storing activity and less weight gained.
Omega-3 Supplements
Taking Omega-3 fish oil capsules is a great way to get the benefits of fish oil without eating fish. You can also use one tablespoon per day of flaxseed oil to get your daily dose of Omega-3. Adult men need roughly 1600 mg of Omega 3 fatty acids per day. Women need at least 1100 mg per day. If you're a woman who is pregnant or breastfeeding, you should increase your daily intake to 1500 mg.
While excess consumption of other types of fat can lead to obesity, heart disease and high cholesterol, essential fatty acids like Omega 3 and Omega 6 can improve your health and well being.
Both Dr. Randy Wysong & Diana Walker are contributors for EditorialToday. The above articles have been edited for relevancy and timeliness. All write-ups, reviews, tips and guides published by EditorialToday.com and its partners or affiliates are for informational purposes only. They should not be used for any legal or any other type of advice. We do not endorse any author, contributor, writer or article posted by our team.
Dr. Randy Wysong has sinced written about articles on various topics from Health, Bankruptcy Chapter 11 and Bankruptcy Law. Dr. Wysong: A former veterinary clinician and surgeon, college instructor in human anatomy, physiology and the origin of life, inventor of numerous medical, surgical, nutritional, athletic and fitness products and devices, research director for the presen. Dr. Randy Wysong's top article generates over 22200 views. to your Favourites.
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