People should eat at least two servings of fish each week, according to the American Heart Association. However, not everybody likes fish. Those who aren't fond of fish can get their omega-3 fatty acids by taking fish oil capsules. Although this type of oil is beneficial, it can be dangerous in large amounts.
Omega-3 fatty acids, the type in fish oil, are very good for your heart. Fish oil contains docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). The DHA and EPA in fish oil can slightly lower blood pressure, slow down the growth of atherosclerotic plaque and lower triglyceride levels, states the American Heart Association. However, taking high doses can keep your blood from clotting.
The World Health Organization recommends that people consume 0.3 to 0.5 grams of a combination of EPA and DHA daily. However, many people take more than this. Up to 3 grams of omega-3 fatty acids a day through fish oil is generally regarded as safe, according to the U.S. Food and Drug Administration.
There are some common side effects with fish oil, including fishy-tasting burps, upset stomach, diarrhea and bloating. Those who are allergic to fish obviously shouldn't take fish oil capsules. Those with bleeding disorders or diabetes should be cautious when taking fish oil, since consuming large amounts of fish oil might make these conditions worse, according to the Mayo Clinic website. Many of the side effects are dose responsive, meaning the more fish oil you take the higher the chance you have of experiencing the side effects.
It can be dangerous to take too much fish oil. Taking more than 3 grams of fish oil supplements daily should only be done under the supervision of a doctor. Large amounts can lead to blood in the urine, nose bleeds and even hemorrhagic strokes. It can also lead to a weakened immune system, according to the National Institutes of Health. If you have liver disease, are on medication for high blood pressure, have been diagnosed with depression or bipolar disorder you should not take fish oil without first consulting your physician.
Because omega-6 fatty acids and omega-3 fatty acids compete for absorption and Americans typically consume more of omega-6 fatty acids, one way to increase the benefits that you get from omega-3 fatty acids without taking large amounts of them and risking overdose is to decrease your intake of omega-6 fatty acids, according to Medline Plus.