Vitamin F: The Essential Fatty Acids
Fats have been getting a lot of press lately – mostly negative. After all, we are a nation of overweight people who DO consume far too much fat. Adults and children over 2 years old should keep their fat intake to approximately 10%-25% of their total daily caloric intake. Infants have a higher fat requirement of about 50% of total calories for proper development of their nervous systems. Because fat consumption must be restricted, the type of fat consumed becomes crucial, especially in developing infants and children. What your child eats is exactly what his cells become. It can also be very important for adults, especially if they have chronic inflammatory or immune problems.
There are 2 types of dietary fats – saturated and unsaturated. Saturated fats are solid at room temperature and are the ones usually associated with heart disease. They are not considered essential because the body can make what it needs.
Unsaturated fats are liquid at room temperature, and therefore less stable than saturated fats. Our bodies can make most of the unsaturated fat it needs, except linoleic and alpha-linolenic acid. These two fatty acids are considered essential because we must obtain them from our diets in order to survive.
There are two main families of essential fatty acids (EFA’s), omega-6 and omega-3 fatty acids. The omega-6 fatty acids include linoleic acid (LA) and arachadonic acid (AA). Linoleic acid is found in sunflower, safflower, sesame, and corn oils.
Under normal circumstances, LA converts to Gammalinoleic Acid (GLA). If this is blocked, however, GLA must be obtained from the diet; sources are evening primrose oil, borage seed oil, black current seed oil, and grape seeds. Breast milk also contains GLA, which is essential in infants under 1 years of age as they lack the necessary enzymes to convert LA to GLA.
Arachadonic acid is found in animal products such as meat, dairy, and eggs. AA can also be synthesized from LA. Arachadonic Acid will be produced if excess amount of omega-6 fatty acids are consumed; this is not desirable as AA causes inflammation and reduced immunity.
The omega-3 Fatty Acids consist primarily of Alpha-Linolenic Acid (LNA). Flax oil is the best source, but it is also found in pumpkin seeds, soybean oil, and walnuts. Under normal circumstances, LNA is converted to Eicosapentaenoic acid (EPA) and Docosahexaenoic Acid (DHA). If enzymes are impaired, however, EPA and DHA must be obtained from the diet by consuming mackerel, salmon, and sardines. Vegetarians can take a supplement called Nueromins in which the DHA is derived from algae.
The main reason the essential fatty acids are so important are that they are ultimately converted into a family of compounds called prostaglandins (PG’s). Prostaglandins are hormone-like chemicals which perform numerous functions – including immune system enhancement and inflammation regulation.
There are 3 main families of prostaglandins, called PG1, PG2, and PG3. Linoleic acid is converted to PG1, arachadonic acid to PG2, and alpha-linolenic acid to PG3. PG1 and PG3 enhance immunity and control inflammation. PG2, however, produces inflammation and is immune-suppressing.
Many substances can block the normal enzymatic reactions from LA to PG1 and LNA to PG3. These include ingestion of saturated fats, trans fatty acids (hydrogenated oils, margarine, fried foods) and sugar, cortisone, environmental chemicals, heavy metals, and viruses, such as Epstein Barr Virus (EBV) . When PG1 and PG3 are prohibited from being synthesized, the immune system becomes depressed and any inflammatory process is allowed to proceed unchecked.
Nutrients which enhance the conversion processes include Vitamins A, B6, C, folic acid, magnesium, zinc, and copper. If these co-factors are not present in sufficient amounts, enzymes will not be able to convert the EFAs into prostaglandins.