Fish Oil for Autism: Could EPA, DHA Benefit Autism & ADHD?

When it comes to autism, there is still no clear clarification as to whether fish oil is beneficial for treating associated symptoms for autism spectrum disorder (ASD).

However, for many years now there have been persistent rumblings – both anecdotal and from several research studies – supporting the use of fish oils for ASD.

In part, the issue is that many of the studies have involved small groups of participants and are too short in duration. Several have been multi-functional as well, with inadequate focus and clarification on certain specifics.

Nevertheless, there is an enduring glimmer that points to the potential benefits of fish oil in some of this research, and there is undoubtedly enough testimony to warrant further, more in-depth investigation.

Read on to learn more.

The National Autistic Society describes autism as a spectrum condition and ‘a lifelong developmental disability that affects how people perceive the world and interact with others.’

It is not an illness or disease and cannot be ‘cured’, and while autistic people share certain symptoms and difficulties, they are unique individuals and are affected in varying ways.

Aside from difficulties with social communication and interaction, some autistic people also have mental health issues, learning disabilities and other conditions including ADHD, hearing impairment, visual impairment, Down’s syndrome and epilepsy.

It’s estimated that one in one hundred people in the UK have autism, with more boys being diagnosed than girls.

Over the years, there has been a growing interest in alternative treatments for ASD including vitamins, gluten- and casein-free diets, melatonin and the use of omega-3 polyunsaturated fatty acids (PUFAs) or fish oils.

According to Agostoni et al. (2017), omega-3 fats have been of interest for their use in treating ASD due to the part they play in brain development, structure and function, neurotransmission, cell membrane structure and function, inflammation, oxidative stress and immunity.

Fish oils in particular have an increasing body of evidence mounting in their favour when it comes to the importance of EPA and DHA for brain structure and function, and their use is often promoted for various neurodevelopmental disorders including ASD and ADHD.

Deficient or low levels of omega-3s have been linked to both autism and ADHD. One recent meta-analysis of various trials involving participants with ASD found them to have lower blood concentrations of EPA and DHA, with a high omega-6 to omega-3 ratio.

With unhealthy proportions like these linked to increased inflammation, it’s hardly surprising that elevated levels of numerous inflammatory markers as well as Nuclear Factor-kappaB (a proinflammatory signalling pathway) have been identified in autistic children.    

In 2006, a survey showed that 27.8% of families reported treating their autistic children with fish oils, and there are many personal accounts from parents of how high doses of fish oil have improved various symptoms of their child’s autism.

Although it can take some time before positive results are seen, parents have observed improvements in learning ability and expressive language, with a resulting amelioration in frustration and aggression.

In 2006, Maria Hutchings shared her experience in The Daily Mail of how supplementing with fish oils ‘unlocked’ John Paul, her autistic son and ‘woke him up’.

Over time, his speech went from a two-word level to seven-word sentences, and at the time of the article, he was reading the Oxford school series and was drawing more expressive and colourful pictures. John Paul’s behaviour had improved dramatically and his frustration levels diminished. He was more empathic and showed remorse after lashing out.

It has been noted among parents that continued supplementation is needed, otherwise symptoms can regress.

While it had a mixed reception, and there were question marks over the trial, that same year (2006) a study of 70 autistic children aged between 6 and 11 years, showed that 40% of them improved dramatically after supplementing with fish oils, with advances in eye contact and socialising. A further 30% showed some positive change after supplementation.

In her trial, Dr Portwood observed that 7% of supplemented children, who mostly had Asperger’s syndrome, no longer expressed any symptoms at all.

Dr Portwood’s advice to parents is to look for signs of insufficient fatty acid levels in their children such as dry, flaky skin, eczema, asthma, lactose intolerance in babies and pin-prick spots on the skin.

Currently, a small amount of research shows the potential of fish oil supplementation to help children with ASD, particularly in the area of hyperactivity.

It’s clear that more specific, longer-running studies with larger groups of respondents need to be carried out to give the positive effects of fish oils on AHD a fair trial. 

In a 2009 systemic review of omega-3 fatty acids for ASD, out of 143 potential articles, Bent, et al. only found six that satisfied their inclusion criteria (whatever that was). Out of those studies, though deemed small and insignificant, a 2007 trial showed minor improvements in hyperactivity and stereotypy, while a further four showed improvements in language and learning skills, anxiety, general health and behaviour.

Due to the limited amount of evidence in its favour, Bent et al. subsequently surmised that there was insufficient evidence to support the use of fish oils as a safe and effective form of treatment in ASD.

It is important to note that the 2007 trial which showed only minor and ‘insignificant’ improvements in hyperactivity and stereotypy, only ran for six weeks on 13 children. It begs the question, might there have been more substantial improvements if the trial had continued for an extended period?

The children had autistic disorders accompanied by severe tantrums, aggression, or self-injurious behaviour. They took a 1.5g daily dose of fish oils (700mg EPA and 700mg DHA).

Between 2008 to 2009, Bent, et al. performed a pilot study ‘with a longer duration of treatment and a larger sample size to examine the feasibility, safety and efficacy of administering omega-3 fatty acids for the treatment of hyperactivity and the core symptoms of ASD.’

The 27 children in the study were given a split daily dose amounting to 1.3g fish oils daily (700mg EPA and 460mg DHA), and the trial ran for 12 weeks against a placebo group. Although the study did not find a statistically significant benefit from fish oil, they did show a small improvement in hyperactivity (2.7 points on the Aberrant Behavior Checklist compared to 0.3 points in the placebo group).

This was only a pilot study to determine whether more research is needed. Moreover, as the researchers pointed out themselves, the classification of ‘no statistically significant treatment effect’ was ‘the most conservative interpretation’ of this study and ‘because pilot studies generally have small sample sizes, the resulting effect estimates are unreliable and therefore decisions regarding the need for future, larger studies should not be based on the results of pilot studies alone’.

They proposed that the small but positive results in both their and the 2007 study might provide some limited evidence that omega-3 fatty acids could have a small, beneficial effect on ASD related hyperactivity. The fish oils were well tolerated with no side effects.

A small 12-week study in 2012, meanwhile, showed significant improvement in the social impairment of individuals with autism spectrum disorders after supplementing with high doses of ARA (arachidonic acid) combined with DHA.

In their 2017 systemic review of ‘The Role of Omega-3 Fatty Acids in Developmental Psychopathology: A Systematic Review on Early Psychosis, Autism, and ADHD’, Agostoni et al. explain that as red blood cell fatty acid levels take up to six months to stabilise and at least four months is needed to demonstrate the effect of omega-3 fatty acids on cognitive function, study periods of a year may be required to show more significant ASD behavioural changes in response to fish oils.

As the Western dietary intake of omega-3 PUFAs is low, it is necessary to investigate the potential of fish oil supplementation for ASD further.

Dr Nina Bailey (BSc, MSc, PhD, RNutr), a nutrition scientist, believes that the EPA in fish oils can be of significant benefit to those with ASD. She states that supplementing with EPA can help to protect and rebuild the protective fatty acid layer around nerve fibres in the brain to enable effective brain signalling.

In a 2009 ‘igennus’ article by Mina Nazemi, Dr Baily states that ‘Individuals with autism appear to have a high turnover of long chain fatty acids and EPA can inhibit the action of the enzymes that are involved in releasing fatty acids from cell membranes, and may, therefore, help to protect all long-chain fatty acids from degradation.

‘Furthermore, autistic children tend to have elevated levels of pro-inflammatory cytokines, high levels of which are associated with an overactive immune system and excess inflammation.

‘EPA directly promotes the production of anti-inflammatory cytokines and inhibits the productions of pro-inflammatory cytokines which target areas of inflammation and helps to restore balance.’

According to Dr Brian M Udell, Medical Director of The Child Development Center of America, when it comes to fish oils, ‘improvements have been documented in behaviour, ADHD, communication and cognitive function – many of the core symptoms of ASD.’

He observes that while more research is needed, some reports document improvements in speech and language amongst other things. He also states that there is a growing body of anecdotal reports and stories observing improvement from supplementing with various omega products.

Udell believes that PUFAs are a standard dietary requirement. As children with ASD tend to be picky eaters, are often on restrictive diets, and have lower blood levels of omega-3 PUFAs, he suggests that supplementing with fish oils is beneficial.

Dr Udell further recommends that to determine whether they are helping, parents should observe and record any improvements in the most documented areas of development, i.e. ADHD (hyperactivity) and aggression.

He also highlights the importance of being aware of safe fish oil dosages and noting any adverse effects.

The ADHD Foundation describes Attention Deficit Hyperactivity Disorder as one of the most common childhood disorders. It is a potentially lifelong condition which can improve with age, continuing through adolescence and into adulthood.

Someone with ADHD can struggle with attentiveness, have difficulty controlling their behaviour, be impulsive and hyperactive.

According to the NHS, symptoms include being easily distracted, making careless mistakes, appearing forgetful or losing things, being unable to listen to or carry out instructions, having difficulty organising tasks, being unable to sit still – especially in calm or quiet surroundings, continually fidgeting, being unable to concentrate on tasks, excessive talking and physical movement, acting without thinking and having little or no sense of danger.

People with ADHD may also suffer from sleep problems and anxiety disorders. They may have other related conditions such as depression, ASD, Tourette’s syndrome, epilepsy and learning difficulties including dyslexia.

There has been a fair amount of research in the area of omega-3 PUFAs and ADHD. However, in their systemic review of the role omega-3 fats play in ADHD, Agostoni, et al. (2017), state that after pooling all these studies it’s very apparent that they are incredibly diverse, varying in size, duration and the type and dosage of supplementation. In other words, it is difficult to come to a definitive conclusion about how effective fish oils are.

That said, several trials have shown significant benefits. Moreover, according to this systemic review, something of note is that beneficial studies consistently have larger sample sizes of 50 people or more and a minimum duration of 15 weeks compared to the studies with negative findings that run for a shorter length with a smaller pool of participants.

A 2008 case-control study found that teenagers with ADHD had lower levels of DHA and omega-3 fats and a high ratio of omega-6 to omega-3. Interestingly, lower omega-3 levels correlated with increased behavioural symptoms.

Agostoni et al. also note that several studies have reported a significant relationship between low blood omega-3 PUFAs and ADHD symptoms, while low blood levels of DHA and EPA are also associated with increased inattention and hyperactivity.

A preliminary study in 2007 involving 132 children with ADHD over 15 weeks, found that supplementing with GLA (omega-6) combined with EPA and DHA showed important medium-to-strong beneficial effects in the areas of hyperactivity, inattention and impulsivity.

Another 2008 trial ran for 30 weeks, where children with ADHD were split into two control and one placebo group. For the first 15 weeks, one of the control groups was given a PUFA supplement of GLA, EPA and DHA combined, while the other control group were given the same PUFAs plus multivitamins and minerals.

For the final 15 weeks, all the children were given PUFAs plus multivitamins and minerals. After the first half of the trial, both PUFA groups showed significant improvements in a test of the ability to switch and control their attention compared to the placebo group. However, after the final 15 weeks, the placebo group also showed the same improvements after changing to PUFA supplementation.

A more recent 2015 study ran over 16 weeks and gave 40 boys with ADHD, and 39 typically developing boys, 650mg EPA and 650mg DHA daily. The outcome was positive for both sets of boys versus the placebo group, with parents observing a significantly positive effect on their attention span.

In 2013, a four-month trial by Milte, et al. showed improved spelling and literacy, hyperactivity and behaviour in the children who supplemented with high daily doses of either EPA or DHA.

Finally, in 2011, a three-month study involving 147 children with ADHD, supplemented them daily with EPA and DHA. Using various questionnaires and the Conners’ parent and teacher rating scales, parents reported significant improvements in both restlessness and impulsiveness compared to the placebo group.

Children who continued with the supplements had sustained improvements, while those in the placebo group who switched to supplementing with fish oil showed significant improvements too.

In 2010, Gustafsson et al. supplemented 92 children with ADHD with a daily dose of 500mg EPA. Their teachers rated their behaviour over a 15-week period and noted a definite improvement in the attentiveness of kids from two ADHD subgroups (oppositional and less hyperactive/impulsive children), although no significant change was observed for hyperactivity.

According to Agostoni et al. (2017), a small group of studies supplementing with higher levels of EPA to DHA have found a positive effect on visual sustained attention performance, delayed memory and working memory function.

In 2013, another systemic review was performed titled ‘Omega-3 Fatty Acid Supplementation for the Treatment of Children with Attention-Deficit/Hyperactivity Disorder Symptomatology’.

Ten trials involving 699 children were taken into account, and small but significantly positive results in ADHD symptoms were found with omega-3 supplementation. The researchers learned that positive results correlated with EPA doses within the supplements.

They concluded that “Omega-3 fatty acid supplementation, particularly with higher doses of EPA, was modestly effective in the treatment of ADHD.”

Although deemed insignificant, a recent 2016 study on 144 children with ADHD noted that higher doses of EPA to DHA improved symptoms of hyperactivity and inattention when rated by parents using the Conners’ Parent Rating Scale. 

As it currently stands, there is an enduring and compelling link, both anecdotal and research-based, between fish oil supplementation and a significant improvement of symptoms in those with ASD or ADHD.

Although there has been much valid research showing both positive and negative results for EPA and DHA supplementation, it is clear that more long-term studies with larger test groups are needed.

This article was written by Rebecca Rychlik-Cunning, Nutritional Therapist and Homeopath. Follow Rebecca on Instagram, Facebook and Medium, @rebeccabitesback.