Fish Oil Facts: Everything You Need to Know
Medically Reviewed by Madeline Hubbard, RN, BSN
While the taste of fish may not be appealing to all taste buds, fish oil supplements offer an additional dietary source of omega-3 fatty acids, which help your body function in a variety of ways. In this article, we'll explore the many health benefits of fish oil, where it can be found and how much you should be taking each day to maximize its positive effects.
What Does Fish Oil Do?
Though it has been linked to a number of health benefits, fish oil is most commonly associated with the health of the heart and its surrounding vessels, which is also called cardiovascular health. Consuming fish oil has been proven to lower fats called triglycerides, which can reduce the risk of heart disease and diabetes. In some studies, fish oil supplements have been shown to lower triglyceride levels by up to 20% to 50%, which is beneficial in preventing heart disease. Keep in mind, however, that in addition to taking fish oil, individuals who want to lower their risk for heart disease should also increase their physical activity and reduce the amount of unhealthy fat in their diets.
In addition to reducing the risk of heart disease, fish oil can also cause minor reductions in blood pressure levels. That's because omega-3 fatty acids have the ability to increase dilation of blood vessels, alleviating high blood pressure. This also helps people with atherosclerosis, a condition in which fatty materials build up along their artery walls.
Atherosclerosis can physically block portions of the arteries and potentially lead to blood clots that cause heart attacks or strokes. Consuming fish oil can help to relieve this problem by reducing the narrowing of the arteries and limiting the production of the fatty materials that may collect on vessel walls.
There are a number of other health benefits that have been linked to fish oil. For example, fish oil may help people with rheumatoid arthritis recover faster from the stiffness they feel when they wake up in the morning. Fish oil can also reduce the risk of having a stroke by as much as 27%, though this reduction is not nearly as dramatic if an individual is already taking aspirin for this purpose. Taking fish oil regularly may prevent the onset of osteoporosis, especially when combined with a regular calcium regimen. Fish oil is also linked to eye health because it can help to prevent age-related macular degeneration and chronic dry eye syndrome.
Lastly, fish oil may also help with brain function. Some studies suggest that fish oil can help to increase blood flow to the brain during cognitive tasks. This can result in improvements in memory and reaction time.
Food Sources of Fish Oil
Even though omega-3 fatty acids are essential for human health, the human body can’t make them on its own. That's why we have to get them from food or supplements. Significant amounts of fish oil can be found naturally in a wide variety of fish. Among the more common fish that are rich in these oils are tuna, salmon, anchovies, sardines and trout.
Other fish that may be less common but that are also rich in omega-3 fatty acids include mackerel, sturgeon, mullet, bluefish, herring and menhaden. In general, you will obtain about 1 gram of fish oil for every 3.5 ounces of fish that you consume. Keep in mind that it’s far better to eat fish that has been baked or broiled; fish that has been fried may actually increase health risks rather than reduce them.
As mentioned, you don't have to eat fish regularly to get the omega-3 fatty acids that you want in your diet. Fish oil supplements are readily available at most health food stores and pharmacies in pill form. Most of these supplements are made from the fish oil from mackerel, halibut, cod liver, salmon or tuna. They may also be made from whale blubber or seal blubber.
These supplements are often combined with vitamin E to prevent spoilage. Be sure to check the label carefully before purchasing a fish oil supplement, as many also incorporate other vitamins, calcium or iron. If you plan to add a fish oil supplement to your diet, talk to your healthcare provider first to make sure that the supplement is safe for you to use.
Daily Dosage Recommendations and Prescription Considerations
It's important to ensure that your diet contains a sufficient amount of fish oil. A deficiency of omega-3 fatty acids can lead to symptoms like poor memory, fatigue, dry skin, mood swings, depression, poor circulation and heart problems. Additionally, infants who don't receive an adequate amount of omega-3 fatty acids during pregnancy may develop vision and nerve problems.
Adults should try to consume fish regularly for its many health benefits. As far as supplements go, most adults should not take more than 3 grams of fish oil daily without first consulting a healthcare provider. Individuals with coronary heart disease or high cholesterol are often encouraged to take an omega-3 fatty acid supplement daily. For healthy adults, eating fish at least twice a week is sufficient for getting the fish oil they need in their diet.
There’s no established dosage recommendation for children. In general, fish oil supplements aren’t recommended for children at all. While it’s healthy for children to receive omega-3 fatty acids naturally by eating fish, children should not be served any fish that may have high mercury content, such as swordfish or mackerel.
Fish oil may cause some minor side effects, such as gas, bloating, belching and diarrhea. If you choose to take a supplement, try looking for time-release caplets to reduce these symptoms. Avoid taking more than 3 grams of fish oil daily without first consulting your healthcare provider.
Certain medications — such as blood thinners, diabetes medications, cholesterol-lowering medications, topical steroids and anti-inflammatory drugs — may have interactions when combined with fish oil. Be sure to ask your doctor about taking fish oil if you’ve been prescribed any of these medications.