You have probably heard that eating healthy means cutting down on fats. Yes, it’s best to limit the chicken fry, cheeseburgers, and potato wedges. But not all fats are bad for you. Some can help your brain and heart work. And some can help your baby develop in the womb. Omega-3 fatty acids are the good kind of fat. They are the essential fatty acids. They are necessary for human health but the body cannot make them; you have to get them through food.
Omega-3 fatty acids can be found in fish, such as salmon, tuna, and halibut, other seafood including algae and krill, some plants, and nut oils. Also known as polyunsaturated fatty acids (PUFAs), omega-3 fatty acids play a crucial role in brain function, as well as normal growth and development. They have also become popular because they may reduce the risk of heart disease. The American Heart Association recommends eating fish (particularly fatty fish such as mackerel, lake trout, herring, sardines, albacore tuna, and salmon) at least 2 times a week.
Research shows that omega-3 fatty acids reduce inflammation and may help lower risk of chronic diseases such as heart disease, cancer, and arthritis. Omega-3 fatty acids are highly concentrated in the brain and appear to be important for cognitive (brain memory and performance) and behavioral function. In fact, infants who do not get enough omega-3 fatty acids from their mothers during pregnancy are at risk for developing vision and nerve problems. Symptoms of omega-3 fatty acid deficiency include fatigue, poor memory, dry skin, heart problems, mood swings or depression, and poor circulation.
It is important to have the proper ratio of omega-3 and omega-6 (another essential fatty acid) in the diet. Omega-3 fatty acids help reduce inflammation, and most omega-6 fatty acids tend to promote inflammation. The typical American diet tends to contain 14 – 25 times more omega-6 fatty acids than omega-3 fatty acids, while the Mediterranean diet, on the other hand, has a healthier balance between omega-3 and omega-6 fatty acids. Many studies have shown that people who follow this diet are less likely to develop heart disease. The Mediterranean diet emphasizes foods rich in omega-3 fatty acids, including whole grains, fresh fruits and vegetables, fish, olive oil, garlic, as well as moderate wine consumption.
- Omega 3 fatty acids improve the cardiovascular risk profile of subjects with metabolic syndrome, including markers of inflammation and auto-immunity.
- Omega-3 in modest doses reduces cardiac deaths, and in high doses reduces nonfatal cardiovascular events.
- Omega-3 fatty acids reduce the total mortality and sudden death in patients with left ventricular systolic dysfunction.
- Raising levels of omega-3 fatty acid in blood may be 8 times effective than distributing automated external defibrillators (AEDs), and 2 times more effective than implanting cardioverter defibrillators (ICDs) in preventing sudden death.
- Omega-3 fatty acids and vitamin D supplementation results in a substantial reduction in coronary calcium scores and slowed plaque growth.
- Omega-3 fatty acids prevent atrial fibrillation after coronary artery bypass surgery.
- A combination of omega-3 and omega-6 fatty acids as well as magnesium and zinc consumption provides a beneficial effect on attention, behavioral, and emotional problems of children and adolescents.
- Fish oil supplementation has a significant therapeutic effect on children with autism.
- The consumption of omega-3 fatty acid supplements decreases homocysteine levels in diabetic patients.
- Omega-3 fatty acids improve endothelial function and blood viscosity in peripheral arterial disease.
- Omega-3 fatty acid supplementation reduces inflammatory biomarkers, erythrocyte sedimentation rate, and interleukin-8 concentrations in cystic fibrosis patients.
- Omega-3 fish oil reduces the severity of symptoms in patients with systemic lupus erythematosus.
- Fish and long-chain omega-3 fatty acid intake reduce the risk of coronary heart disease and total mortality in diabetic women.
- The consumption of fish reduces the risk of ischemic stroke in elderly individuals.
- Omega-3 fatty acids may have a therapeutic effect on postpartum depression.
- Omega-3 fatty acid supplementation exhibits therapeutic value in the treatment of children with attention-deficit/hyperactivity disorder (ADHD).
- Omega-3 fatty acids prevent the formation of urinary calcium oxalate stone formation.
- Omega-3 fatty acids are beneficial for children with bronchial asthma.
- Fish consumption is associated with a 63% reduction in prostate cancer-specific mortality.
- Cod liver oil (omega-3 fatty acids) reduces the need for NSAIDs in patients with rheumatoid arthritis.
- Omega-3 fatty acids have an inhibitory effect on breast cancer growth and metastasis.
- Dietary Omega-3 fatty acids may protect smokers against chronic obstructive pulmonary disease (COPD).
- Omega-3 fatty acids were shown to be more effective than placebo for depression in both adults and children in small controlled studies and in an open study of bipolar depression.
- A diet low in trans-unsaturated fat and rich in omega-3 fatty acids and olive oil may reduce the risk of age-related macular degeneration.
- Higher intake of omega 3 fatty acids may reduce the risk of pneumonia.
Fish, plant, and nut oils are the primary dietary source of omega-3 fatty acids. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are found in cold water fish such as salmon, mackerel, halibut, sardines, tuna, and herring. ALA is found in flaxseeds, flaxseed oil, canola (rapeseed) oil, soybeans, soybean oil, pumpkin seeds, pumpkin seed oil, purslane, perilla seed oil, walnuts, and walnut oil. The health effects of omega-3 fatty acids come mostly from EPA and DHA. ALA from flax and other vegetarian sources needs to be converted in the body to EPA and DHA. Many people do not make these conversions very effectively, however. This remains an ongoing debate in the nutrition community; fish and sea vegetable sources of EPA and DHA versus vegetarian sources of ALA. Other sources of omega-3 fatty acids include sea life such as krill and algae.
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Bahadori B, Uitz E, Thonhofer R, et al. omega-3 Fatty acids infusions as adjuvant therapy in rheumatoid arthritis. JPEN J Parenter Enteral Nutr. 2010; 34(2):151-5. [/sws_yellow_box]
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