Probably the major risk of overdosing on fish oil is the contamination, more specifically mercury contamination. It is a sad fact, but a lot of the world’s fishing grounds are contaminated or polluted. The fish you eat might have a good stock of omega-3 but you might not know it, the fish might only contain a considerable amount of heavy metal contaminants. When it comes to pill or capsule supplements, the process of creating those fish oil capsules might not be safe. The safest would be through a distillation process.
Another major risk is when combined with other blood thinners. Fish oil acts as a blood thinner or anti-coagulant, which basically helps stop platelets or heavy cells from forming blood clots reducing the risks of having a heart attack. However, if you combine fish oil with other medicines such as aspirins, the result might be very harmful to your body and even fatal. Too much blood thinners can cause you to bleed out. And bleeding does not mean just bleeding out externally, but there are cases where patients actually bled to their brains.
So going back to our question, is fish oil harmful? Well, the above scenario is quite a frightening one but things like that could possibly happen to people who are extremely careless. That is why before you take any supplements, fish oil in this case, you should consult your doctors and make sure you provide them with a complete, honest and proper medical history.