Omega-3 fatty acids can help protect your heart by reducing blood triglycerides, helping to keep your heart's rhythm regular, and keeping your blood pressure normal. Eating a diet rich in omega-3 fatty acids also helps keep your arteries clear from plaque buildup that can lead to heart attacks and strokes.
Omega-3 fatty acids are also crucial for brain and eye development in fetuses and newborns, so women need to get adequate amounts when they're pregnant and during the first few months of breastfeeding. Omega-3 fatty acids have also been studied for their effects on your nervous system, and they may also help relieve dry eyes and dry skin. Some experts believe they may fight aging by affecting your DNA.
Types of Omega-3 Fatty Acids
There are three types of omega-3 fatty acids: docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA) and alpha-linolenic acid (ALA). The first two types, DHA and EPA, are found in fish and other animal sources, and they're the form used in your body. The third form, ALA, is found in plant-based foods. Your body can convert the ALA form to either DHA and EPA.
Oily ocean fish, especially salmon, herring, tuna, sardines and trout, have the highest omega-3 fatty acid content. The American Heart Association recommends most people eat fish twice each week. However, because of the potential for mercury contamination in fish, pregnant woman and children should probably avoid eating too much fish.
You can also find omega-3 fatty acids in grass-fed lean beef, and in eggs laid by hens fed ALA-enriched feed. Plant sources of omega-3s include flax seeds, walnuts, pumpkin seeds, soy, and canola oil. There's no concern for mercury in any of the plant forms of omega-3 fatty acids, so you can eat them every day.
Omega-3 dietary supplements are often used therapeutically to reduce inflammation, lower triglycerides, and reduce blood pressure. They're also used to help reduce the symptoms of other disorders such as asthma, depression and dementia, although the research isn't as clear about the effectiveness of omega-3s for these conditions.
Note: taking large doses of omega-3 supplements can interfere with some medications, so be sure to talk to your doctor first if you have a medical condition.
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