Concerns that fish oil supplements may increase the risk of bleeding – a potential concern for people undergoing surgery – are unfounded, according to a systematic review the scientific literature published in the Danish Medical Journal. The aim of the review was to evaluate the effect of fish oil supplements on haemostasis and bleeding risk, and to provide recommendations on whether it is necessary to discontinue fish oil supplementation prior to surgery. Clinicians have expressed concern about a potentially increased bleeding risk during surgery in patients.
Fish oil supplements reduced platelet aggregation in healthy subjects. This biochemical effect was not reflected in increased bleeding risk during or after surgery evaluated in randomized controlled trials. Consequently, this systematic review does not support the need for discontinuation of fish oil supplements prior to surgery or other invasive procedures.