The Dietary Management of Autism – Dietetically Speaking (2023)

This article, which discusses the interesting topic of diet and autism, was originally published in the February 2018 edition of NHD Magazine.

Autism is described as a lifelong developmental disability which can present in a range of ways, including: cognitive differences, sensory differences, communication differences, social differences and certain medical and mental health issues^1-3.

Autism is also associated with unique strengths such as: good memory of facts, logical thinking skills and awareness of small details^1,3.

Some of these differences can present challenges in terms of dietary intake, this can include: overeating, undereating, restrictive eating (or avoidant restrictive food intake disorder in severe cases), pica, difficulty with meal presentation or the eating environment, continuous grazing or ritualistic eating¹.

This article discusses the practical management of dietary issues in the context of children with autism.

Dietitians can support a family to maximise the nutritional adequacy of their child’s diet; including advice on food substitutes and use of supplements as needed¹.

Faltering growth is more commonly seen in younger children with autism; often because of gastrointestinal issues and/or restrictive eating². Whereas, older children with autism seem more predisposed to becoming overweight; often due to a high intake of refined carbohydrates, sweet foods and savoury snacks, and a low intake of fruit, vegetables, wholegrains and fish².

Although selective eating is an extremely common feature of autism, reassurance should be given if the child is growing well in order to reduce parental anxiety¹.

Severe autism is associated with lower levels of calcium, iron, zinc, vitamin C, vitamin B3 and vitamin B6⁴.

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As with the general public it is also important to consider vitamin D status⁵. Correcting vitamin and mineral deficiencies in children with autism using appropriate supplements is advised as a first line treatment, which should be followed by other strategies to improve overall nutritional intake¹.

However, achieving the recommended intake of micronutrients may be challenging as supplements may be refused, so a relaxed and pragmatic approach is usually best¹. Unflavoured supplements, such as paediatric Seravit (SHS) can be better tolerated than flavoured versions; but this specific supplement needs to be combined with a fish oil supplement to provide essential or long chain fatty acids (examples include: Ideal Omega Swirl (Barlean’s), Lem-0-3 (Cytoplan), MorEPA and MorDHA (Nutritional Intelligence))².

It is also important to monitor for signs of anaemia in those with a low iron intake; as advice on iron intake and/or iron supplementation may be indicated⁶.

Additional time is often needed in dietetic consultations, and it can be helpful to alter sensory aspects of the clinic setting to suit the individual where possible. For example, if a child with autism is hyper-auditory it is a good idea to limit the noise in the clinic room by closing windows, or if they are hyper-visual it may be helpful to reduce the amount of visual stimuli in the room (bright lights, colourful wall displays etc.). Equally, if a child is hypo-visual it may be useful to incorporate visual elements into the session.

In terms of mealtimes, some children with autism eat more when sitting with other people, whereas others prefer to eat by themselves⁴. Similarly, some children find it difficult to eat in a noisy atmosphere, but others eat better when there is music or a video playing in the background^2,6.

Extra consideration may also be needed to account for sensory preferences for: specific cutlery or utensils, foods of specific colours or textures and overall food presentation¹.

For example, children with autism often dislike mixed textures, such as milk and cereal together, so may prefer to have these presented separately¹. If eating in a different environment (such as a restaurant) it can be helpful to prepare in advance by discussing where they will be going, who will be there, where they will be sitting and what they could speak to people about at the table⁶.

Similar to environmental adjustments it is important to adapt communication accordingly. Depending on the client this may include: the use of visual prompts, limiting the use of hand gestures, not overloading with instructions, using short closed questions, speaking more slowly, awareness of nonverbal communication, using consistent and specific language to discuss food, limiting ambiguous humour and sarcasm and incorporating the child’s interests and strengths into the session⁷.

Useful visual resources include: rewards charts, food planners, picture books, ‘Social Stories’ (developed by Carol Gray in 1991), the Picture Exchange Communication System (PECS), ‘Just Look & Cook’ visual cook books and ‘Dinner Winner’ trays^6-7.

Reducing stress at mealtimes and creating a positive food environment is crucial^1,4. Successful strategies vary a lot between individuals but sensible tips are outlined in the information box below^2,6.

This gradual approach, also referred to as ‘food-chaining’, introduces new foods by linking from a current ‘safe food’ to a similar food (such as a different brand or shape of bread stick) and continuing in a stepwise manner as outlined in the charts below⁶.

This includes encouraging the child to touch, smell, lick and taste new foods and praising these actions even if the new food isn’t tolerated straight-away⁶.

It is also important to explain that this process can take a long time; in some cases significant progress can include: accepting being in the same room as a certain food, or accepting this on the plate without eating it. It is usually sensible to avoid ‘contaminating’ accepted foods with new foods by presenting them on separate plates and starting with a small amount of a new food then titrating upwards if tolerated.

Occupational therapy-led oral desensitisation programs can also be very useful¹, these can include the use of brushes, massages, blowing bubbles, use of chewy tubes and ‘chewlery’.

A ‘food exchange’ is a similar approach where a food’s features are assessed and a food with similar qualities is exchanged for this (see table below – ‘Sensory Characteristics of Food Exchange system from p. 180 of the Manual of Dietetic Practice, 5th Edition)².

As with any dietetic consultation it is important to use motivational interviewing techniques to support behaviour change, such as: rolling with resistance, accurate empathy and being led by the client and/or their family.

It is also key to set realistic goals in the context of autism, rather than trying to resolve all food related issues¹.

With family members and some older children, it can be useful to explore psychological strategies such as cognitive behavioural therapy to de-catastrophize fears related to food.

Another relevant strategy is the ‘ABC of behaviour’ (as outlined below); this can help to identify whether the child is reacting to the food itself or to another environmental factor.

Keeping a food diary can also help to identify patterns of food refusal. A detailed food diary can include: the time, what was eaten, where was it eaten, volume consumed, response to the meal, who was present, other environment factors etc⁶.

It is crucial that all goals are clear and consistent between everybody involved in the child’s care, including the client, family members and carers. Autism outreach teams and The Autism Society can provide great support and resources for families. Working with speech and language therapy for those who have poor oral motor skills or extreme oral sensitivity can also be very important. And as mentioned above, occupational therapists can assess and clarify the child’s sensory profile and develop a suitable desensitisation programme¹.

As each case is unique it is important to provide an individualised treatment plan based on a detailed dietary assessment.

For example, the BDA highlight that standard healthy eating guidelines are often inappropriate for those children with autism who have an extremely limited diet (i.e. those who eat less than 20 types of food)¹. It is also important to explore the underlying issues for eating difficulties; such as sensory or social differences⁶. Some common nutritional issues, which may need to be considered on a case by cases basis, are listed in the table below^1,6.

To account for the numerous differences which can occur in autism, there are many aspects of dietary care to consider. This can include: monitoring growth and nutritional intake, correcting micronutrient deficiencies, making environmental and communication adaptations, encouraging positive and relaxed mealtimes, supporting with desensitisation to new foods and the use of psychological strategies.

Ensuring that treatment is individualised and working closely with other members of the multidisciplinary team, as well as family members, are also key aspects of supporting children with autism from a dietary point of view.

1. BDA (2010) “Dietary Management of Autism Spectrum Disorder”
2. Manual of Dietetic Practice (5th Edition)
3. The National Autistic Society (NAS) website “Autism” [accessed December 2017 via: http://www.autism.org.uk/about/what-is/asd.aspx]
4. BDA Food Fact Sheet “Autism”
5. SACN (2015) “Draft Vitamin D and Health report”
6. NAS website “Eating” [accessed December 2017 via: http://www.autism.org.uk/about/health/eating.aspx]
7. NAS website “Communicating” [accessed December 2017 via: http://www.autism.org.uk/about/communication/communicating.aspx]
8. Zoe Connor Dietitian (2011) “An Introduction to Autism – For Dietitians”