Home HealthTopics Health Centers Reference Library Research
Join us on Facebook Join us on Facebook Share on Facebook

Research Center

Benefit and Risks of Fish Oil Supplements



My seven year old son has PDD with autistic characteristics. I have been hearing that fish oil supplements can help with the symptoms of autism. What dose(s) of EPA and DHA and GLA have been found to be effective? I bought a fish oil supplement but I am afraid it would be too much...can a child overdose on these type of supplements?


Searching the scientific literature for autism and fish oil or PDD and fish oil, there are only two references in the scientifically reviewed literature, neither which gives a dose for the fish oil. Checking Google, more references appear but from the ones that I reviewed came from manufacturers and distributors of fish oil products, some claiming there are references that support their use. Checking the authors in the scientific literature fails to bring up any papers. This is not to say that it does not work or that it will work, it merely describes the current state of the literature. I have included the references below, and some of the abstract information.

My recommendation with any treatment that does not have sufficient support in the scientific literature is to ask two questions; in what ways might it help and in what ways might it hurt.

The question of help is not yet able to be answered - if the websites that claim there have been studies, those studies will be submitted to journals and reviewed for their scientific merit and published if they were well done studies.

The second is the question of harm, several possible problems have been reported including; stomach upset, increased bleeding tendency, increased cholesterol/caloric intake, Vitamin A & D toxicity, presence of fat soluble contaminants in addition to relatively bad tasting burping. I am certain this relates to dose taken and the particular product chosen and the environmental contamination the fish were subject to.

That being said, personally I do not see support for or against their use, likely if dosed conservatively (and with a contaminant free product) they will not likely cause harm. If you are going to use them, I would discuss it with your child's health care provider and with their approval try the lowest dose possible, increase slowly (but not beyond what is given by the manufacturer or your child's primary care provider) and monitor carefully for any side effects.

Literature references:

Young G. Conquer J. , Omega-3 fatty acids and neuropsychiatric disorders in Reproduction, Nutrition, Development. 45(1):1-28, 2005 Jan-Feb.

The abstract states "Epidemiological evidence suggests that dietary consumption of the long chain omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), commonly found in fish or fish oil, may modify the risk for certain neuropsychiatric disorders. As evidence, decreased blood levels of omega-3 fatty acids have been associated with several neuropsychiatric conditions, including Attention Deficit (Hyperactivity) Disorder, Alzheimer's Disease, Schizophrenia and Depression. Supplementation studies, using individual or combination omega-3 fatty acids, suggest the possibility for decreased symptoms associated with some of these conditions. Thus far, however, the benefits of supplementation, in terms of decreasing disease risk and/or aiding in symptom management, are not clear and more research is needed."

Bell JG. MacKinlay EE. Dick JR. MacDonald DJ. Boyle RM. Glen AC., Essential fatty acids and phospholipase A2 in autistic spectrum disorders. Prostaglandins Leukotrienes & Essential Fatty Acids. 71(4):201-4, 2004 Oct.

The abstract states, "A health questionnaire based on parental observations of clinical signs of fatty acid deficiency (FAD) showed that patients with autism and Asperger's syndrome (ASP) had significantly higher FAD scores (6.34+/-4.37 and 7.64+/-6.20, respectively) compared to controls (1.78+/-1.68)….Patients diagnosed with both autism and ASP showed significantly increased levels of EPA ( approximately 200%) and DHA ( approximately 40%), and significantly reduced levels of ARA ( approximately 20%), 20:3n-6 and ARA/EPA ratio in their RBC polar lipids, when supplemented with EPA-rich fish oils, compared to controls and non-supplemented patients with autism."

Benefit vs. Risk of Fish/Fish Oil
Sidhu KS, Health benefits and potential risks related to consumption of fish or fish oil, Regulatory Toxicology & Pharmacology. 38(3):336-44, 2003 Dec.

For more information:

Go to the Research Center health topic, where you can:

Response by:

Michael Spigarelli, MD, PhD
Formerly, Associate Professor of Pediatrics and Internal Medicine
College of Medicine
University of Cincinnati