In a small but rigorous six-month study, omega-3 fatty acid supplements produced no benefits over dummy pills in the autism symptoms and language development of toddlers and preschoolers with autism.
The study, by researchers at Toronto’s Bloorview Kids Rehabilitation Hospital, appears online in the journal of Molecular Autism. The hospital is part of the Autism Speaks Autism Treatment Network (ATN).
Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are important for brain development and function.
“During the last trimester of fetal life and the first two years of childhood, the brain undergoes a period of rapid growth,” the researchers write by way of background. “DHA is required for the development of the sensory, perceptual, cognitive and motor neural systems during the brain growth spurt.” EPA, in turn, is found in breast milk and plays a significant role in brain and immune function.
Their clinical trial followed up on questions raised by a series of earlier studies. Some of these studies found that children with autism, as a group, tend to have lower levels of omega-3s than do typically developing children. But other studies failed to find such differences.
The new study enrolled 38 children with autism (28 boys and 10 girls), ages 2 to 5. Half received a liquid supplement containing 1.5 grams each of EPA and DHA. This is the maximum dose of omega-3 fatty acids recommended by Health Canada (the equivalent of the U.S. Food and Drug Administration). Because omega-3 supplement can cause gastrointestinal upset, the children started with a dose of 0.75 grams, and then increased to the full dose after two weeks if no problems arose.
For comparison, the other 19 children received flavored olive oil prepared to look and taste the same as the omega-3 liquid supplement.
After six months, the researchers performed standardized evaluations of autism symptoms, problem behaviors and language development. The results showed no benefits over a placebo, or dummy pill. In fact, those in the treatment group experienced a slight worsening of challenging behaviors such as disruptiveness, aggression and hyperactivity.
“Despite the disappointing results, this new study is commendable,” comments Autism Speaks Head of Medical Research Paul Wang, who was not involved in the study. “The investigators enrolled younger children than in any other study of omega-3 supplementation and provided treatment for a longer period than in any other study. Both of these features were designed to maximize any effect that the supplement might have.”
The study also went further than previous trials by drawing blood to ensure that the children were actually swallowing and absorbing the omega-3 fatty acids. The findings support those of studies giving omega-3 supplements to older children with autism. These likewise found no benefit.
“The biggest limitation of the study was its small size,” Dr. Wang adds. “However, one shouldn’t underestimate the difficulty of running even a relatively small, high-quality clinical trial such as this one. This is a huge effort not only for the researchers but for the families who make sure their children receive the treatment each day and have to bring their children into the clinic for monthly evaluations and blood draws. We are tremendously appreciative of their contribution to this important research.”
Learn more about enrolling in autism studies on our “Participate in Research” page. Also see Autism Speaks Participant’s Guide to Drug Research.
To learn more about research on autism and nutritional supplements, also see: