In a previous blog we covered briefly what fish oil is and what omega 3 fatty acids are. We also looked at some health claims. Here we will look at the potential benefits for athletes.
Why would athletes need fish oil?
Despite 100+ publications investigating fish oil supplements in athletes over the past 25 years, there were no systematic reviews collating the evidence and providing a consensus of opinion, specifically for the evidence in elite athletes;
It is known that training leads to improvements in omega-3 status, namely increases in the Docosahexaenoic acid (DHA (22:6n–3)) content of cell membranes [2], which may result in athletes by virtue of years of training having less or no need for supplementation with fish oil supplements. However, expert groups, such as the International Olympic Committee and the American College of Sports Medicine were either reportedly, “unclear if fish oil supplements should be pursued by athletes” or offered no guidance. Therefore a comprehensive analysis of the existing literature was performed.
What did we find?
We found that fish oil supplements exert consistent positive effects on cognition and mood, cardiovascular dynamics (in cyclists), and muscle recovery. In addition, that fish oil supplements attenuate pro-inflammatory cell responses (i.e., TNF-alpha) and increased lipid peroxidation and post-exercise nitric oxide. No benefits for fish oil supplements were seen on endurance exercise performance, training adaptations, muscle force, or lung function (other than in cases of exercise induced bronchoconstriction (EIB)).
"... fish oil supplements exert consistent positive effects on cognition and mood, cardiovascular dynamics (in cyclists), and muscle recovery".
No benefits for fish oil supplements were seen on endurance exercise performance, training adaptations, muscle force, or lung function
Negative effects of fish oil
What was important to establish was any evidence for a negative effect of fish oil supplement supplementation on performance. Indeed, any reported side effects were mild, although we did identify one case of a duodenal ulcer associated with high dose fish oil intake. It was noteworthy that many of the randomised controlled trials (RCT) that reported positive effects for fish oil supplements, used doses that were achievable through the consumption of oily fish in the diet; a fact which should not be lost given the concerns expressed over supplemental fish oil quality in the scientific literature (summarised in the review). With regards to dietary sources, DHA and EPA are natural constituents of seafood including algae, crustaceans, and to a much a lesser extent dairy and meat (the diet of the animal influencing the omega 3 fatty acid content).
Fish oil supplements and concussion
Prior to commencing the systematic review, we had become increasingly aware of a growing interest in the application of fish oil supplements as a preventative agent for concussion in athletes, and as a post-injury treatment adjunct to medical management for head injuries resulting from either a military or non-athletic related head trauma [3,4]. Our systematic review methodology captured only one RCT in athletes reporting a beneficial effect of DHA specifically, on lowering a biomarker of neuronal injury in American footballers. Although this is indeed a positive outcome from the use of DHA, it is perhaps disappointing that no studies have been completed to date with regards to investigating the effect of DHA on recovery from concussion. Moreover, we reported that there is also a need to further our understanding of the impact of fish oil supplementation on neuromuscular performance, bone metabolism, rehabilitation from injury (e.g., surgical compared with nonsurgical outcomes including bone stress), EIB, risk of illness, and risk of sudden cardiac death in athletes.
"RCTs that reported positive effects for FS, used doses that were achievable through the consumption of oily fish in the diet".
What can we do now for the athlete?
We should firstly measure omega-3 status in order to capture fatty acid profiles that gives us greater objectivity in answering whether a given athlete would benefit from fish oil supplementation; certainly, avoiding any deficiencies is paramount. Recognising that athletes who follow a vegan diet are at high risk of DHA and EPA inadequacy. In fact, we should encourage the consumption of dietary sources where the athlete is open to such advice. Secondly, we should consider monitoring the athlete’s omega-3 status periodically to allow for adjustments to the supplementation regime where necessary and recognise that DHA and EPA can exert significant positive effects on the athlete’s physiology.
We should firstly measure omega-3 status in order to capture fatty acid profiles that gives us greater objectivity in answering whether a given athlete would benefit from fish oil supplementation
What are the take-away messages?
There are 3 main take-away messages from our study:
Some clear evidence for beneficial effects of fish oils/eating oily fish in athletes, but boo clear effects on the main outcomes like
Measurement and monitoring of omega-3 status allows for objectivity around the need for use of supplementation with fish oils.
Despite some promising results to date, more research is needed.
Conclusions.
In conclusion, the last ~25 years of research has uncovered several applications for FS in athletes, that said, we are still only at the infancy of the application of fish oil supplements in protecting the athlete from the effects of concussion and TBI.
References.
Lewis NA, Daniels D, Calder PC, Castell LM, Pedlar CR. Are There Benefits from the Use of Fish Oil Supplements in Athletes? A Systematic Review. Advances in Nutrition 2020; 11(5): 1300-14.
Helge JW, WuBJ, Willer M, Daugaard JR, Storlien LH, Kiens B. Training affects muscle phospholipid fatty acid composition in humans. Journal of Applied Physiology 2001; 90(2): 670-7.
Bailes, J. E., & Patel, V. (2014). The potential for DHA to mitigate mild traumatic brain injury. Military medicine, 179 (suppl_11), 112-116.
Lewis MD. Concussions, Traumatic Brain Injury, and the Innovative Use of Omega-3s. Journal of the American College of Nutrition 2016; 35(5): 469-75.