“If the DHA and EPA are not available, the brain will use omega-6 to substitute and it will work, but it’s like running a high-performance engine on low-octane gas. So it will run, but not optimally,” Arnold says.
Fish oil supplements will work, but fish is ideal because of the protein, with the caveat that fish also may be contaminated with mercury. Mercury is an important consideration when buying supplements, he adds, recommending supplements that are labeled to say the mercury and heavy metals have been eliminated or that they are US Pharmacopeial Convention (USP) grade.
The study is not intended to change clinical practice, Arnold says, but was an offshoot of a larger study called the “Omega-3 and Therapy Study for Childhood Bipolar Disorder–Not Otherwise Specified (OATS),” a clinical trial of psychoeducation and psychotherapy and omega-3 fatty acids for mood disorders in children and adolescents.
To truly understand the best dosing and determine a recommendation for clinical practice, more studies are needed.
Arnold says his team is working to secure funding for follow-up studies to delve into the question of optimal dosing, and the best ratio of EPA to DHA. In the meantime, supplements would benefit healthy children, but would be particularly useful as a therapeutic intervention for children with mood disorders. “[For] any child that [pediatricians] are prescribing a drug to for some emotional or mental problem, whether depression or ADHD, they should also be prescribing omega-3 fatty acids,” he says.
Studies have been published using as little as a gram of fish oil for ADHD and depression in children and are showing good results, and other studies using larger amounts also show good results, Arnold notes.
“This particular study suggests that it’s possible to get too much of a good thing, and maybe less is more,” he says. “The kids with the larger body mass had better effect from the omega-3 fatty acids even though the increase in their blood level was less.”
This could be in part because the older/larger children had larger bodies to disperse the dose, but also because the omega-3s may have been sequestered into the adipose tissue of the larger/older children. Age also may play a role in the metabolism and/or storage of omega-3 fatty acids, but more research is needed to say for certain, Arnold says.
“We need to have studies of relative doses to find the optimal dose. In the meantime, I would say a gram a day is good for you and it’s not too much. Two grams is tolerable and safe,” Arnold says.
1. Christian LM, Young AS, Mitchell AM, Belury MA, Gracious BL, Arnold LE, Fristad MA. Body weight affects omega-3 polyunsaturated fatty acid (PUFA) accumulation in youth following supplementation in post-hoc analyses of a randomized controlled trial. PLoS One. 2017;12(4):e0173087.