What is it and what does it do? Fatty acids are the building blocks of dietary fats. The human body stores such dietary fats mainly in the form of triglycerides. Triglycerides containing omega-3 fatty acids are mainly found in fish. What is it and what does it do? Fatty acids are the building blocks of dietary fats. The human body stores such dietary fats mainly in the form of triglycerides. Triglycerides containing omega-3 fatty acids are mainly found in fish. Essential fatty acids The bulk of fat contained in our diet are the triglycerides. The triglycerides contain three saturated fatty acids, and two unsaturated fatty acids, DHA and EPA.. Fats with a high content of saturated fatty acids are solid at room temperature, butter and fat from red meat, for example. Fats with a high content of unsaturated fatty acids are soft or liquid at room temperature, for instance, soft margarine, plant oils and fish oil. The terms saturated and unsaturated refer to the chemical structure of the fatty acids. Unsaturated fatty acids have one or several double bonds. In omega-3 fatty acids, the double bonds start at the third carbon atom counted from the Omega end. In omega-6 fatty acids, the double bonds start at the sixth carbon atom. Although animals and humans are not able to produce them naturally, polyunsaturated fatty acids are essential for normal life functions. They are therefore characterized as essential fatty acids. Polyunsaturated fatty acids are produced by various plants. They reach man through the food chain, either directly through the consumption of fruit and vegetables, or by eating the flesh or eggs of animals, birds or fish that have eaten plants containing the polyunsaturated fatty acids. Essential polyunsaturated fatty acids can be classified as belonging to one of two “families”, the omega-6 family or the omega-3 family. Fatty acids belonging to these two families differ not only in their chemistry, but also in their natural occurrence and biological function. Omega-6 fatty acids are typical of the polyunsaturated fatty acids found in terrestrial plants and they will be present in that part of the food chain. Omega-6 oils are found in cooking oils such as corn oil and soybean oil. Omega-3, on the other hand, is produced by marine plankton and is heavily represented in the marine food chain. The most important source is fat fish. The nutritional gap While the recommended daily intake of marine omega-3 fatty acids should be in the range 0.6 – 1 gram, a “normal” diet in the Western world only satisfies about 10-15% of this requirement. The remaining requirement, the “nutritional gap”, can be covered by increasing one’s consumption of fat fish or by using suitable dietary supplements. An insufficient intake of omega-3 fatty acids may increase the risk of cardiovascular disease. Deficiencies of essential polyunsaturated fatty acids may cause a wide variety of symptoms, including retarded growth in babies and children, reduced fertility and pathologic changes in the skin. “The dietary ratio of Omega-6 to Omega-3 should be about 4/1.” Given a daily energy intake of 2500 kcal, people should eat about 0.6 – 1 g of EPA and DHA, and at least 0.2 – 0.3 g of it should be DHA(Marine Omega 3 Fatty Acids). The biological importance of polyunsaturated fatty acids The reason behind these apparently unrelated symptoms is the central role that polyunsaturated fatty acids play in the cell membrane, the “wall” surrounding all living cells. The composition and structure of the cell membrane is very important for maintaining normal cell function. All nutrients and waste substances have to be transported through the cell membrane. The same happens to biological products produced by the cells, i.e. hormones or other substances used by other cells in the body. Another important function of polyunsaturated fatty acids containing 20 carbon atoms (C20) and particularly arachidonic acid (omega-6) and eicosapentaenoic acid (omega-3) is that they can be converted to locally functioning transmitter substances that are important for biological processes such as blood clotting, inflammatory reactions and muscle contractions. Among these transmitter substances prostaglandins and leukotrienes are the best studied. Another important function of polyunsaturated fatty acids is that they are vital components of brain tissue and other nerves. The omega-3 fatty acid, docosahexaenoic acid (DHA), is particularly important. A normal adult brain contains more than 20 grams of DHA! DHA also plays an important role in the composition of the retina of the eye. It is therefore also of major importance for vision. Fat fish is the primary source of marine omega-3 Research among native Greenlanders in the early 1970s opened the eyes of the medical and nutritional world to the importance of a “new” dietary factor: marine omega-3 fatty acids. Importance of a “new” dietary factor: Marine omega-3 fatty acids (essential fatty acids) Metabolism of fatty acid families: Omega-3 a linolenic acid becomes EPA, which in turn, becomes DHA. Omega-6 linolenic acid becomes GLA, which then becomes Arachidonic acid. Omega-3 fatty acids are an important part of the cell membrane in all cells. They: • reduce the production of inflammatory transmitter substances • are important components for the development and maintenance of brain tissue, other nerve tissue and the retina • lower serum triglyceride levels are a potential adjunct to modify certain mental disorders One of the first countries to start performing significant research along these lines was Japan. Unlike the diet in Greenland, the Japanese diet is low in fat. Similar to the diet in Greenland, however, the Japanese diet has a relatively large proportion of fish and seafood. Consequently, it is high in marine omega-3. The incidence of cardiovascular disease is very low, making Japan among the world leaders in terms of life expectancy. The acceptance of marine omega-3 fatty acids as benefiting health in general is increasing worldwide. The value of omega-3 fatty acids as a supplementary treatment for patients suffering from certain diseases is also increasingly accepted. As a consequence, products containing omega-3 fatty acids are registered as pharmaceuticals or natural medicines in a number of countries. Marine Omega-3 Oils and the Health Authorities Generally, a daily intake of 0.6 – 1 grams of omega-3 fatty acids in the form of EPA and DHA is recommended as a dietary supplement. Based on views expressed by international experts at a recent meeting in Washington, D.C., this recommendation concerns an adequate intake of the various fatty acids. Daily doses of more than 3 gram are used when omega-3 fatty acids are used to treat specific diseases. Why do we need EPA and DHA? Healthy adults have a certain ability to metabolize alfa-linolenic acid to EPA and DHA. Babies do not have this ability and are entirely dependent on receiving these essential elements through what they eat. The ability to metabolize EPA and DHA may also be reduced in elderly people. “Marine omega-3 is considered to have no adverse effects in the doses recommended.” Breast milk contains omega-3 fatty acids in the form of both EPA and DHA. Giving omega-3 supplements to the mother will increase the content of omega-3 in the breast milk. Omega-3 fatty acids, particularly DHA, are important for the normal development of the brain and of vision. It is therefore regrettable that most breast milk substitutes do not contain any long chained omega-3 fatty acids. Increasing importance attached to EPA and DHA Today, it is accepted by the medical society that omega-3 fatty acids lower serum triglycerides and used as a treatment of hypertriglyceridaemia. Based on the estimates produced by the GISSI Prevention study, up to 20 lives are expected to be saved per 1000 patients treated with Omacorª. Clinical observation shows that omega-3 fatty acid reduces mortality with 20 % in heart attack patients and play an important role in preventing cardiovascular disease. Omega-3 and the medical profession Research into the biological and clinical effects of marine omega-3 fatty acids was originally initiated by physicians. The profession is still working to learn more about the importance of essential fatty acids for a healthy life. To date, clinical research has resulted in more than 6000 scientific publications worldwide, and the research continues. Cardiovascular diseasesMarine omega-3 lowers serum triglyceride levels, reduces blood pressure and stabilizes the rhythm of the heart. It lends itself for use both as a prophylaxis and as an adjunct treatment for cardiovascular disease. Rheumatoid arthritis There is also growing appreciation for clinical documentation on the reduction of symptoms in patients suffering from rheumatoid arthritis. Pregnancy and breast feeding The value of omega-3 during pregnancy and breast feeding is becoming increasingly clear. Omega-3 is important for the development of the brain, nervous tissue and retina. A fetus or a baby can only get these essential nutrients from its mother. Depression A high dietary intake of marine omega-3 has been linked to a delay in the development of senile dementia and possibly to reducing symptoms that have already manifested themselves. There have also been reports of positive effects from the dietary intake of omega-3 fatty acids in patients suffering from depression. “Worldwide, more than 6000 scientific publications on marine omega-3 research had been published as of the end of 1998.” Cerebral dementia Dietary marine omega-3 has also been associated to delay the development of cerebral dementia in elderly people. Other diseases Recent scientific publications have reported positive effects on a number of clinical conditions, including migraine, heart arrhythmia, mental cognition in adults and attention deficit/ hyperactivity disorder in children. A large number of clinical trials are currently in progress. For any queries, please consult your GP or the Zoi Wellness center at 9141688 for further information. Dr Costa Kapnias has been a GP in Cape Town for 14 years and qualified at the University of Cape Town. He has spent the last 8 years practising preventative and anti-aging medicine. 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