Whether you eat fish or not, adding a fish oil supplement to your daily vitamin regimen offers many health benefits. Cold-water fish contain several polyunsaturated fats, collectively known as omega-3 fatty acids. They go a long way toward promoting better health. In fact, the omega-3 fatty acids found in abundance in fish and fish oil supplements may offer protection against cardiovascular disease, maintain optimal nerve function and reduce inflammation.
Fish is good for you. It is an excellent source of protein, some vitamins and minerals, is low in total and saturated fats, but, most importantly, it is rich in omega-3 fatty acids. The two "disease-fighting" ingredients found in fish oil are called docosahexaenoic acid -- DHA -- and eicosapentaenoic acid -- EPA. People who consume seafood-rich diets experience less heart disease. Fish oil may help fight colon and breast cancers, and reduce lung inflammation. Many health experts agree that aiming for 1,000 milligrams daily of a blend of EPA and DHA omega-3s -- from fish oil capsules -- is safe and effective for most people.
Currently, there is no Dietary Reference Intake -- DRI -- for the omega-3 fatty acids. Due to the increasingly convincing evidence that a higher intake of omega-3 fatty acids is associated with better health, the National Academies have recommended that about 10 percent of the Acceptable Macronutrient Distribution Range -- AMDR -- for the precursor fatty acid, alpha-linolenic acid -- ALA -- , be consumed as EPA and/or DHA, which adds up to about 100 milligrams per day. This amount is significantly less than what experts consider to be a therapeutic amount. However, the American Heart Association now recommends all adults eat fatty fish at least twice weekly to lower the risk of developing coronary heart disease -- CHD -- , while those with CHD should consume 1 gram per day of EPA and DHA.
A Healthier Heart
The omega-3 fatty acids, EPA and DHA, are heart-protective in many ways. Consuming EPA plus DHA at a therapeutic dose of approximately 1 gram per day is beneficial for suppressing heart arrhythmias, or irregular heart beats. At doses greater than 3 grams a day, fish oil may improve other heart disease risk factors, such as decrease serum triglyceride levels -- blood fat -- , lower blood pressure, keep blood platelets from sticking together -- forming harmful blood clots -- and reduce inflammation, all of which improve the reactivity of the vascular system. EPA and DHA reduce blood pressure by inhibiting the body's production of eicosanoids, naturally occurring pro-inflammatory compounds -- including prostaglandins, leukotrienes, and thromboxane. In large amounts, these compounds cause blood vessels to constrict.
Fish oil also protects the heart by increasing the levels of "good" high-density lipoprotein -- HDL -- cholesterol. HDL helps keep fatty plaque from depositing in the arteries. Fish oil may even offer benefits for those who have already had a heart attack. Fish oil helps keep arteries from closing after angioplasty -- a procedure that opens clogged blood vessels in the heart.
Cancer and Lung Health
Saturated and trans fats are unhealthy, but not all fats are bad. Those found in fish oil appear to be particularly protective against colorectal and breast cancers. EPA and DHA may work against cancer the same way they work to protect the heart, by reducing the body's production of eicosanoids, in particular, prostaglandins. Prostaglandins promote tumor growth. Abnormal tumor growth is characteristic of cancer. Even moderate consumption of fish oil -- 1 gram three times weekly -- seems to reduce the risk of tumor growth.
Anyone suffering from a condition that involves inflammation, due to pro-inflammatory eicosanoids, may benefit from taking supplementary EPA and DHA. Fish oil may help ease the breathing of those with Chronic Obstructive Pulmonary Disease -- COPD. This condition is caused, in part, by long-term smoking and drastically reduces the capacity of the lungs to move oxygen in and out effectively. Omega-3 fatty acids -- along with antioxidant vitamins and plant flavonoids -- reduce inflammation via cell signaling and gene expression as well as reduce the damage caused by free radicals. These benefits may extend to those suffering from asthma.
Although further research is needed, fish oil is thought to play a role in strengthening the immune system, especially in people with impaired immune fuction. Because not all individuals, especially Americans, consume enough fish to reap these benefits, adding a fish oil supplement that offers at least 1 gram of EPA plus DHA daily, is a good idea. Anyone taking medication to thin the blood or blood pressure medication should check with their physician prior to taking fish oil supplements.
- Cleveland Clinic Journal of Medicine; What can we expect from omega-3 fatty acids; E.J. Chan and L. Cho
- Prostaglandins, Leukotrienes, and Essential Fatty Acids; Dietary reference intakes for DHA and EPA; P.M. Kris-Etherton, J.A. Grieger and T.D. Etherton
- American Journal of Clinical Nutrition; n-3 fatty acids and cardiovascular disease; J.L. Breslow