While fish oil is renowned for its potential health benefits, it's essential to be aware of potential negative effects of fish oil. In some instances, consuming excessive amounts of fish oil supplements may lead to adverse outcomes. High doses can thin the blood, increasing the risk of bleeding and bruising. Moreover, individuals with certain medical conditions, such as bleeding disorders or those taking blood-thinning medications, should exercise caution and consult a healthcare professional before adding fish oil to their regimen. Excessive consumption might also result in gastrointestinal discomfort, including nausea, diarrhea, or indigestion.