There has been a tendency, in both conventional and integrative medicine, to frequently recommend that patients stop taking all fish oil supplements prior to surgery due to the theoretical concern that it may increase the possibility of bleeding. What recent research has shown, however, is that taking fish oil prior to surgery not only fails to increase one’s bleeding risk, but has the potential to actually lower a patients risk of bleeding during and following surgery.


Fish oil has been extensively studied, researched and used for its many health promoting benefits. From heart health, brain development, to mental health and many benefits in between, fish oil is a go-to for its prominent and accepted health advantages. From the interchangeable references omega 3, short chain fatty acids, omega fatty acids as well as others, each refer back to fish oil as the primary source of nutrition. So what’s the big concern about fish oil and bleeding? Let’s quickly review and then set aside the former in place of the actual safety and efficacy of this mighty and welcomed nutritional supplement.


As it was, fish oil has been demonized over the past several decades for its negative impact on human health. From it’s reference as being a fat that if consumed in too high doses (the doses that since have been shown to be extremely beneficial) could contribute to cardiovascular disease (heart attack and stroke), dangerous blood thinning effects, and generally as an inert concentrated natural medicine that isn’t helpful in any regard. The problem, when it came to the theory on bleeding, was in its height around 2016 when a study indicated that adding fish oil in those who take warfarin (a potent blood thinning medication on its own) created an interaction that further increased bleeding in this particular population. Thankfully, the inaccurate presumptions from this study have since been put to rest. 


Now for those who still aren’t clear on exactly what fish oil is, essentially it’s the oil derived from fish (often times the liver), and contains a highly concentrated amount of omega 3 fatty acids (such as DHA and EPA) that have been repeatedly shown to hugely benefit health. Yes, consuming fatty fish allows those who include it into their diet benefit from the healthy omega fatty acids, however it’s the medicinal concentration of the fish oil (and avoidance of the potential toxins and metals that come along with eating fish alone)  that truly creates the advantages for the consumer. 


So what’s all this talk over whether fish oil is safe or dangerous in those who are undergoing surgery? Because fish oil also has what is called an ‘anti platelet’ benefit (meaning it can reduce an aspect of the blood that contributes to clotting formation), it was blindly assumed that this meant it must increase bleeding time. Thankfully, a study performed in recent years, fully discounted this theory and showed that although fish oil in fact reduces platelet aggragation (reduces clot formation), it does so in a healthy way. What this study also showed was that fish oil does not significantly affect bleeding time in any way, and specifically does not cause increased risk of bleeds. This, my friends, has been wonderful news ever since.


Growing evidence from very complex, detailed and well conducted scientific studies has shown that the former concern of fish oil increasing bleeding time can be put to rest. So why should we ultimately care so much about whether a surgery patient does or doesn’t take fish oil before or after surgery? Given the huge health activities of consuming regular doses of naturally concentrated fish oils, it’s one of those things where if something is creating benefit, then there is no reason for the already overburdened medical system to worry about another concern that ultimately helps patients versus causing harm. As well, what the studies have opened our eyes to, is that not only is fish oil safe in those undergoing surgery, there are actually benefits for those who aren’t taking fish oil to start prior to their surgery date. Not only does fish oil NOT negatively impact bleeding risk in surgery patients, the science has now shown that proper fish oil dosing can actually lower the bleeding risk during and after surgery. 


Now aren’t all those wonderful reasons to speak to your naturopathic or integrative medical doctor about the safety and benefits of consuming your fish oil for better health! 



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Dr Jeremy Hayman, ND helps patients at Cornerstone Naturopathic Inc. feel better, live better, and achieve optimal wellness and health. Years of patient care coupled with dedication to personal life balance has helped Dr Jeremy employ the adage that “your approach to health should be simple”.