Mackerel, herring, tuna, halibut, salmon, cod liver, whale blubber or seal blubber are the usual ingredients that can be found in fish oil supplements, MedlinePlus states. In many cases, small amounts of vitamin E are added to the supplement to help prevent spoilage. Other nutrients such as calcium, iron or vitamins A, B1, B2, B3, C or D are also sometimes added to fish oil supplements. When selecting which fish oil supplement to buy, be sure to read the label and check the amount of omega-3 fatty acid the supplement contains.
Benefits
The components of fish oil that provide a great benefit to the health of your heart are omega-3 fatty acids called docosahexaenoic acid or DHA for short and eicosapentaenoic acid, also referred to as EPA, MayoClinic.com states. Taking both DHA and EPA in the right doses lowers blood pressure slightly, reduces triglyceride levels, lowers your risk of heart attack, strokes and dangerous abnormal heart rhythms, especially when you have heart disease. Fish oil may slow the buildup of dangerous cholesterol plaques in your arteries.
Mechanism
The benefit to cardiovascular health bestowed by taking DHA and EPA appears to come from the way these two omega-3 fatty acids get into the membranes of cells and in the process help improve the heart's electrical activity and vascular tone, Eureka Alert.org states. This action also seems to stabilize the level of plaque in the cardiovascular system as well as the blood pressure. There seems to be an inverse relationship between the number of cardiovascular incidents and the level of EPA and, especially, DHA in the tissues of the cardiovascular system. Furthermore, by lowering triglyceride levels, fish oil helps prevent cardiovascular disease.
Dosing
Healthy adults with no history of heart disease should ideally make fish a part of their diet at least twice a week, the University of Maryland Medical Center recommends. If you suffer from coronary heart disease, you may need to take 1 g of combined EPA and DHA every day. You may need to take 2 to 4 g of combined EPA and DHA if your cholesterol level is high. Avoid taking more that 3 g of omega-3 fatty acids a day because this could increase your risk of bleeding. If you need to exceed this dosage, do so under the supervision of a healthcare provider. Since there is no established dose for children, avoid giving them fish oil except under the direct supervision of a healthcare provider.
Overdosing
Taking more than 3 g of fish oil a day increases your chance of bleeding and may interfere with the ability of your blood to clot, MedlinePlus warns. In addition to this, your body's immune system activity may be reduced, making this a concern if you're elderly or taking medication meant to suppress the activity of your immune system. Aside from this, your levels of 'bad' cholesterol can increase as a result of taking more than the recommended amount of fish oil per day. It will become necessary for you to have your blood tested on a regular basis to ensure that your cholesterol level doesn't become too high.
References
- MedlinePlus; Fish Oil; February 2011
- Mayo Clinic; Omega-3 Fatty Acids, Fish Oil, Alpha-linolenic Acid; April 2011
- Eureakalert.org; Study Reveals Mounting Evidence of Fish Oil's Heart Health Benefits; Amanda Jekowsky; August 2009
- University of Maryland Medical Center; Omega-3 Fatty Acids; Steven D. Ehrlich; June 2009
