Dear John Oliver, et al.:
Thank you for taking interest in our article (1). We appreciate the fact you took time to read and comment on it. We certainly agree with your statement that “Animal models of traumatic brain injury (TBI) clearly demonstrate that ω-3 administration before (2) and after (3) insult confers neuroprotective qualities,” as evidenced by our statement in the article, “The potential neuroprotective benefits of omega-3s are evident from animal studies demonstrating that supplementation before or after TBI protects the brain by limiting structural damage to the axon and neuronal apoptosis.”
We stated that animal studies show benefit from supplementation of DHA when head injury occurs. Studies that looked at preloading and postinjury treatment did not vary significantly in neurologic damage, meaning the changes were similar. We properly cited this statement since it was clearly explained in the citation (4) that you stated, “which is incorrect and inappropriately cited” (4); therefore, we do not believe that studies in animals show a difference in benefit between preloading versus early postinjury treatment. In fact, it was our intention to make a statement that would influence sports medicine physicians to think twice about supplementing all their athletes with DHA prophylactically. We appreciate the compliment that you believe our paper has enough influence, which “may lead to broad policies that inhibit practitioners from supplementing those athletes at risk for sports-related concussion.”
Addressing further comments in your letter, it also is notable that Figure 1, on page 976 in Oliver et al. MSSE 2016 (5) highlights the fact that those football players who received placebo, and those that received 2 g/d of DHA, had no concussions through a college football season but those receiving 4 g/d had 2 concussions, and those who received 6 g/d had 5 concussions. Figure 3 C (5) also highlights that the smallest change from baseline in the biomarker NFL was in those subjects in the 2-g/d arm, with higher changes from baseline in those subjects that received higher dosages of DHA, which puts into question the protective effect of DHA supplementation. Yet, the study concludes “the data presented herein demonstrate that American football athletes likely require a higher dose of DHA than the average population.” This seems irresponsible. Therefore, we believe it is very responsible to stick by our statement “Further work is therefore needed to see if more DHA makes you more likely to become concussed while playing football.”
We have performed research studies on collegiate teams and in the field of concussion, so we appreciate your work looking at ω-3 supplementation in college football players. It takes a lot of time, money, and effort. Perhaps, we may not have made it obvious that we are neither for nor against ω-3 fatty acids. While potential side effects are minimal, human data proving benefit are still lacking. We stick by our comment that “Therefore, if one chooses to use DHA, despite the lack of data, we would suggest it be used postinjury, 10 mg/kg per day or 2 g/d.”
Thomas H. Trojian, MD, FACSM
Drexel University 10 Shurs Lane Philadelphia, PA [email protected]
John J. Leddy, MD
University at Buffalo Sports Medicine Institute University Sports Medicine Buffalo, NY
David H. Wang, MD
Department of Orthopaedics Elite Sports Medicine Connecticut Children’s Medical Center Hartford, CT
The authors declare no conflict of interest and do not have any financial disclosures.
1. Trojian TH, Wang DH, Leddy JJ. Nutritional supplements for the treatment and prevention of sports-related concussion—evidence still lacking. Curr. Sports Med. Rep
. 2017; 16:247–55.
2. Wang T, Van KC, Gavitt BJ, et al. Effect of fish oil supplementation in a rat model of multiple mild traumatic brain injuries. Restor. Neurol. Neurosci
. 2013; 31:647–59.
3. Mills JD, Bailes JE, Sedney CL, et al. Omega-3 fatty acid supplementation and reduction of traumatic axonal injury in a rodent head injury model. J. Neurosurg
. 2011; 114:77–84.
4. Trojian TH, Jackson E. ω-3 polyunsaturated fatty acids and concussions: treatment or not? Curr. Sports Med. Rep
. 2011; 10:180–5.
5. Oliver JM, Jones MT, Kirk KM, et al. Effect of docosahexaenoic acid on a biomarker of head trauma in American Football. Med. Sci. Sports Exerc
. 2016; 48:974–82.