Omega 3 fatty acids are one of two groups considered to be essential; the other being the Omega 6 fatty acid class. Both of these fatty acids are considered essential because the body has no way of manufacturing them, as the builiding blocks needed for creation are absent in human physiology. As well, the human body can not break down other substances in body for Omega 3 and Omega 6 fatty acid conversion. Fatty acids are an essential part of human nutrition. They are the building blocks for all cells and are a necessity in the production of cell signaling molecules known as prostaglandins.
Most fatty acids can be made from precursors, via cellular reactions that either break down the starting molecule or add to it. The essential omega 3 fatty acids that cannot be made from precursors in the body are: eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and alpha-linolenic acid (ALA). Sources for these omega 3 fatty acids are listed below.
Omega 3 fatty acids are considered a natural anti-inflammatory because they favor the production of prostaglandins that are anti-inflammatory, as opposed to those that are pro-inflammatory. These same pathways that produce prostaglandins also make leukotrienes, or substances that are involved in allergic reactions and asthma. The pathways are also responsible for thromboxanes, a substances that regulate the stickiness of platelets, the small cells in our blood that help form clots.
In all of these pathways, Omega 3 fatty acids help to decrease the harmful effects that result from the overproduction of the abovementioned substances. The high intake of animal fats high in arachadonic acid, another fatty acid that causes the production of pro-inflammatory molecules, in our diet creates an imbalance in the developmental system. In no case would it be beneficial to eliminate the production of inflammatory cell signals, because they do provide a service to the body when needed. The goal of supplementation with Omega 3 fatty acids is to provide a healthy balance between the good and bad prostaglandins, leukotrienes, and thromboxanes, in order to avoid disease such as arthritis, asthma, and atherosclerosis.
The most plentiful sources of EPA and DHA include; cod liver oil, halibut oil, and other fish oils. Eating foods such as mackerel, salmon, tuna, cod, halibut, and sardines, also provides for adequate EPA and DHA intake.
Source of ALA include perilla seed oil, flaxseed oil, black currant seed oil, canola oil, walnut oil, soybean oil, and wheat germ oil.
- Omega 3 fatty acids are beneficial for inflammatory disorders of the musculoskeletal system. Because they support the production of anti-inflammatory molecules, they can be an effective addition to treatment protocol specifically designed to inhibit the inflammatory process.
- Omega 3 fatty acids are particularly beneficial for arthritis, especially rheumatoid arthritis. In patients with rheumatoid arthritis, omega 3 fatty acids can decrease the symptoms associated with the disease.  They also cause a decrease in the amount of medication needed to decrease symptoms.  Studies indicate that omega 3 fatty acids work best for rheumatoid arthritis when the ratio of omega 6 fatty acids to omega 3 fatty acids is less than 4:1. 
- EPA, an omega-3 fatty acid, was shown to improve clinical symptoms and psychological parameters in people with schizophrenia. It was well tolerated by the individuals and did not produce any side effects. 
- Omega 3 fatty acids are also helpful for those with bi-polar disorder.  Omega 3 fatty acids were shown to decrease the course of the illness. It also improved symptoms during the course of a manic episode. Omega 3 fatty acids are thought to work similar to lithium and valproic acid, two commonly prescribed medications for bi-polar disorder.
- For those with depression, omega 3 fatty acids have been proven an effective adjunctive treatment.  They are believed to augment the effects of antidepressants, as well as have a positive effect on their own. Omega 3 fatty acids improves symptoms of this condition, especially during major clinical depressive episodes.
- Omega 3 fatty acids are beneficial for individuals with multiple sclerosis. Fish oil has been proven to improve clinical outcome, as well as decrease the rate of exacerbations or episodes during a year.  Dietary advice along with supplementation of omega 3 fatty acids increases this effect.
- Omega 3 fatty acids were shown to decrease the amount of oxidative stress in the bowel of individuals with Ulcerative Colitis.  Fish oils may act as scavengers of free radicals, and also decrease the production of pro-inflammatory markers in the bowel.  Supplementation also was proven effective at altering the cell function and structure in a positive manner. 
- Omega 3 fatty acid supplementation in Crohn’s disease decreases the inflammatory markers in the blood, as well as decreasing the rate of relapse for patients in remission. [11, 12]
- Omega 3 fatty acids are helpful for inflammatory conditions of the respiratory tract. They have been show to suppress the constriction of the bronchioles due to certain inflammatory substances.  Omega 3’s have been helpful for individuals with asthma, by decreasing inflammatory molecules and improving lung function.  They are also considered protective for individuals who suffer from exercise-induced airway constriction. 
- Omega 3 fatty acids may prove beneficial for those with high blood pressure. Supplementation with Omega 3 fatty acids alone has been effective at decreasing both the systolic and diastolic blood pressure readings in individuals with mildly elevated blood pressure. [15, 16]
- Omega 3 fatty acids can also lower blood triglycerides, a lipid responsible for heart disease when present in excessive amounts.  Omega 3 fatty acids can also increase the amount of HDL, or good cholesterol, levels. However, studies have mixed results concerning Omega 3 fatty acids effects on LDL and total cholesterol. 
- Omega 3 fatty acids are helpful for individuals who are obese. They have been proven to lower the risk of heart disease, increase weight loss, and increase the response to insulin in obese individuals. They may also lower blood lipids when combined with weight loss. 
- Omega 3 fatty acids are a welcome addition to any treatment protocol for cancer. They have been shown to decrease the effects of ultraviolet light on the skin, providing protection against the development of skin cancers.  For individuals with late stage cancer who are suffering from cachexia, a wasting syndrome, omega 3 fatty acids stabilizes and helps to increase weight when proper dietary concerns are addresed.  Omega 3 fatty acids have also been effective at prolonging the survival of patients with cancer and cachexia by improving nutritional status. 
- Omega 3 fatty acids are helpful for individuals with certain skin conditions with an inflammatory cause. For individuals with eczema, omega 3 fatty acids decreased the itch, amount of scale, and severity of symptoms. 
The dose of Omega 3 fatty acids can range from 2 grams to 14 grams per day, depending on the condition. Most studies use a dose between 3 and 10 grams of either EPA, ALA, and DHA alone, or in various combinations.
There is no toxicity associated with the intake of Omega 3 fatty acids. High doses may cause diarrhea in some individuals, paralleled with mild stomach upset.
To avoid lipid peroxidation and rancidity of the Omega 3 fatty acids, it is suggested to combine intake with 400 IU of Vitamin E.
Because Omega 3 fatty acids affect the production of thromboxanes, and may have a mild anti-platelet activity, those individuals who are taking medications to thin blood or decrease clots should consult their doctor before beginning treatment with Omega 3 fatty acids.
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