Omega-3 fatty acids are essential fatty acids (EFA), essential to good health. They cannot be created within the human body and must therefore be obtained from the diet.
Some people think that autistic individuals either do not have enough omega-3 or have too much omega-6 in relation to omega-3 in their bodies.
They think that this may cause or worsen some of the symptoms of autism, such as impaired communication and social difficulties.
They also think that these difficulties can be overcome by increasing the amount of omega 3 in the diet or by taking supplements (such as fish oils) which are rich in omega-3.
The National Institute of Health and Care Excellence (NICE) made the following recommendations:
“Do not use omega-3 fatty acids to manage sleep problems in children and young people with autism.” (NICE, 2013).
There is a very small amount of high quality research evidence (13 group studies) and a small amount of low quality research (three single-case design studies with three or more participants) into the use of omega-3 fatty acids as an intervention for autistic people.
Some of those studies have reported benefits (such as increased social communication and interaction and decreased hyperactivity). Some of those studies have reported no benefits of any kind.
There is therefore insufficient evidence to determine if omega-3 fatty acids provide any benefits to anyone who is autistic.
Omega-3 is relatively cheap to obtain and relatively easy to administer, either as a supplement or as part of a diet.
Given the number of anecdotal reports of the benefits of omega-3 fatty acids, we recommend that further large scale, high quality research should take place.
Please read our Disclaimer on Autism Interventions
The aim of taking omega-3 fatty acid supplements is to treat any omega-3 fatty acid deficiency and to increase the amount of omega-3 relative to the amount of omega-6. Some people think this will affect the balance of fatty acids in cell membranes, which could affect brain function and mental health.
Omega -3 fatty acid supplements have been used as a treatment for a range of conditions including in the prevention of heart disease and in some inflammatory disorders.
There have been various claims made for essential fatty acids and autistic individuals. For example, the following researchers have made the following claims
In addition, there have been a number of anecdotal claims for the benefits of essential fatty acids including Patrick and Salik (2005) who reported significant improvements in language and learning skills.
The supporters of omega 3 EFA supplements claim that they are suitable for anybody, including individuals with autism.
Fatty acids are components of fats in our food. Dietary fats not only provide a source of energy for our bodies, but also affect many different aspects of our health. Fatty acids are present in every cell in our bodies and play important roles in heart health, immunity and hormone responses.
Fatty acids are classified as saturated, monounsaturated or polyunsaturated depending on their molecular structure. Essential fatty acids (EFAs) are polyunsaturated fatty acids that cannot be created within the human body and must therefore be obtained from the diet.
There are 2 different families of EFAs – the omega-3 fatty acids and the omega-6 fatty acids.
There are a number of different forms of omega-3 fatty acid including alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).
ALA is found in rapeseed, linseed (flaxseed) and soybean oils, and spreads made from these oils. It is also found in ground linseeds, soyabean products, walnuts, and dark green leafy vegetables.
EPA and DHA are found in the flesh of oily fish such as salmon, herring, mackerel, anchovies and sardines, and in fish oil supplements including cod liver oil.
Omega-3 enriched products such as bread, eggs and milk are also widely available.
There are a number of different forms of omega-6 fatty acid including linoleic acid (LA) and arachidonic acid (AA).
LA is found in safflower, sunflower, hemp and soybeans, and AA is abundant in typical Western diets in vegetable oils, nuts, cereals and animal fats.
The typical Western diet contains much more omega-6 fatty acids than omega-3s. This fatty acid imbalance in our typical diet is thought to have many different negative health effects, including on our mental health and brain function. However, as Innes et al (2018) have noted “The interaction of omega-3 and omega 6 fatty acids … in the context of inflammation is complex and still not properly understood”
Fish oil supplements rich in the omega-3 fatty acids DHA and EPA are widely available from pharmacists, supermarkets and mail order companies. They are available as liquids, capsules and chewable tablets.
Omega-3 fatty acids can be incorporated into a normal diet by eating two portions of fish per week, one of which should be oily fish, and by eating more green leafy vegetables, soya beans and linseed.
Monounsaturated (fat molecules that have one unsaturated carbon bond in the molecule); polyunsaturated (fat molecules that have more than one unsaturated carbon bond in the molecule); saturated (fat molecules that have no double bonds between carbon molecules because they are saturated with hydrogen molecules).
The cost of buying omega-3 supplements depends on a range of factors including the type of supplement, the quantity you buy, the supplier, delivery charges etc.
We found a wide range of suppliers providing omega-3 supplements for a wide range of prices when we did an online search on 9 May 2018. Prices varied from £2.87 for 120 tablets to £75 for 250 tablets.
In the UK, it is sometimes possible to obtain free NHS prescriptions for specific dietary supplements if you have certain medical conditions (such as diabetes) or you are a member of an exempt group (such as being under 16 or over 65).
The amount of time it takes to use omega-3 supplements will depend on a number of factors including the overall length of treatment, the frequency of treatments and the time taken to administer a single dose, as well as the needs of the person undertaking it.
Most omega-3 supplements are designed to be taken once or twice a day, often before mealtimes.
Some researchers suggest that daily omega-3 supplements should be taken for at least 3 months for full effects to be seen. Daily supplementation is generally quick and easy but young children are often reluctant to take supplements.
We would strongly recommend that you review your use of dietary supplements on a regular basis with a responsible health professional such as a dietitian, GP or pharmacist. This is because you are likely to experience some harm if you take supplements in large amounts over long periods of time.
The quality of omega-3 supplements can vary enormously depending on the specific supplement, the manufacturer, the ingredients and the manufacturing process.
Omega-3 supplements are generally safe, however we recommended that you discuss the safe trial of any nutritional supplements with your doctor before using them. We also suggest that you do not exceed the RIs (Reference Intakes) recommended by the Food Standards Agency in UK or the RDAs (Recommended Dietary Allowances) recommend by the Office of Dietary Supplements in the USA.
Particular care is recommended to:
1. Avoid toxins such as mercury, hormones, dioxins, and PCBs, which are present in many fish oils. Supplements are available that have been purified by molecular distillation and which are described as pharmaceutical grade.
2. Avoid toxic doses of vitamin A, which is often included in fish oil supplements. Care should be taken to keep intake within the safe dose as recommended by the UK Department of Health, taking into account vitamin A levels in any additional supplements taken.
3. Avoid supplements containing any ingredients which you or your child or client are allergic or hypersensitive to.
4. Be wary of doses above 1000mg (1 gram) of omega-3 per day.
5. Be aware that fish oils supplements can affect blood sugar control in diabetes.
6. Be aware that high levels of fish oil supplementation can cause blood thinning, which could cause problems in people who bruise easily, self-harm, have a bleeding disorder, or take blood-thinning medications.
Side effects of taking fish oils can include repeating taste, heartburn, diarrhoea, and headaches.
There are very few contraindications (something which makes a particular treatment or procedure potentially inadvisable) for omega-3 fatty acid supplements.
However the National Institutes for Health (2017) noted that
“Omega-3 dietary supplements may interact with the medications you take. For example, high doses of omega-3s may cause bleeding problems when taken with warfarin … or other anticoagulant medicines.”
Notes
Dioxins (toxic chemical by-products of industrial processes); PCBs (polychlorinated biphenyls, synthetic organic chemicals that can cause a number of different harmful effects.)
Omega-3 supplements are available from a wide range of suppliers including health food stores, chemists and pharmacies, professional health care providers and online stores.
If you are contemplating taking omega-3 supplements, you should seek advice from a GP, pharmacist or dietitian. The British Dietetic Association has information about qualified dietitians in the UK.
For children and adults who are not eating a varied and sufficient diet, for example, avoiding food groups, or eating a very restricted diet, a dietitian can help by assessing dietary intake and advising on testing and supplementation where necessary.
All professionals involved with autistic adults and children should watch for potential nutritional problems particularly if their diets are restricted.
There are no formal, internationally validated registered qualifications for most people who provide omega-3 supplements.
However, in the UK, the quality of dietary supplements is regulated by the Medicines and Healthcare Products Regulatory Agency, if they ‘contain a pharmacologically active substance or make medicinal claims (claims to treat or prevent disease, or to interfere with the normal operation of a physiological function of the human body) ...’
In the UK certain supplements are considered to be foods and will therefore be regulated under general food laws by the Food Standards Agency and Department of Health. Others will be regulated as a medicine by the Medicines and Healthcare Regulatory Agency (MHRA).
All herbal medicines placed on the UK market must have a Traditional Herbal Registration (THR)10 or a marketing authorisation (previously known as a product licence). The MHRA now defines individual herbal medicines as either registered traditional herbal medicines or licensed herbal medicines.
In the USA dietary supplements are not classed as drugs, but the Food and Drug Administration is responsible for taking action against any unsafe dietary supplement product after it reaches the market.
Essential fatty acids were discovered in 1920's, when they were called vitamin F. They were re-classified as fats in 1930.
Essential fatty acids began to be used for the treatment of various mental health problems, such as depression and schizophrenia, in the 1990s. They began to be used for the treatment of autism in the 2000s.
We have identified 16* articles published in English-language, peer-reviewed journals which evaluated the efficacy of omega-3 fatty acids as an intervention for autistic people. Three of those articles (Boone et al, 2017; Keim et al 2018; Sheppard et al, 2017) appeared to describe the same study.
The studies we found included more than 300 individuals aged from three to forty - but only one of these studies looked at adults, the majority looked at children and adolescents. A small number of studies also included people with other conditions, such as ADHD.
The majority of the group studies were randomised controlled trials which compared omega-3 supplements with a placebo. One of the studies (Meguid et al, 2008) used a supplement which included omega-6 alongside the omega-3. Another of the studies (Boone et al, 2017) used a supplement which included omega-6 and omega-9 alongside the omega-3. One of the randomised controlled studies (Johnson et al, 2010) compared omega-3 with a sugar-free diet. The four single case designs were open trials which did not compare omega-3 with anything else.
The length of intervention varied from six weeks to 16 weeks but in most cases it lasted between six weeks and three months. The dosage varied from 0.09 grams per day to 1.5 grams per day but in most cases the dosage varied between 1and 1.5 grams per day.
*Please note: We have not included articles with less than three autistic participants or articles which did not examine the efficacy of omega-3 fatty acids as an intervention for autistic people.
There are a number of limitations to all of the research studies published to date. For example
There is a very small amount of high quality research evidence (13 group studies) and a small amount of low quality research (three single-case design studies with three or more participants) into the use of omega-3 fatty acids as an intervention for autistic people.
Some of those studies have reported benefits (such as increased social communication and interaction and decreased hyperactivity). Some of those studies have reported no benefits of any kind.
There is therefore insufficient evidence to determine if omega-3 fatty acids provide any benefits to anyone who is autistic.
There is a need for further research into the use of omega-3 fatty acid supplements for autistic people. Specifically there is a need for studies which
This section provides details of scientific studies into the effectiveness of omega-3 for autistic people which have been published in English-language, peer-reviewed journals.
If you know of any other publications we should list on this page please email info@informationautism.org
Please note that we are unable to supply publications unless we are listed as the publisher. However, if you are a UK resident you may be able to obtain them from your local public library, your college library or direct from the publisher.
This section provides details of other publications on this topic.
You can find more publications on this topic in our publications database.
If you know of any other publications we should list on this page please email info@informationautism.org
Please note that we are unable to supply publications unless we are listed as the publisher. However, if you are a UK resident you may be able to obtain them from your local public library, your college library or direct from the publisher.