Eating and Mealtime Behaviors in Patients with Autism Spectrum Disorder: Current Perspectives
Received 26 June 2020
Accepted for publication 7 August 2020
Published 11 September 2020 Volume 2020:16 Pages 2083—2102
Checked for plagiarism Yes
Review by Single anonymous peer review
Peer reviewer comments 2
Editor who approved publication: Dr Roger Pinder
Lucia Margari, Lucia Marzulli, Alessandra Gabellone, Concetta de Giambattista
Child Neuropsychiatric Unit, University of Bari Aldo Moro, Bari, Italy
Correspondence: Lucia Margari
Child Neuropsychiatric Unit, University of Bari Aldo Moro, Piazza Giulio Cesare, 11, Bari 70124, Italy
Tel +39 80 5592829
Email [email protected]
Abstract: Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by impaired social and communication skills and repetitive and restrictive behaviors. Children and adolescents with ASD are more likely to present feeding problems than their typically developing peers are. The present narrative review of literature aims to highlight the most recent evidence about epidemiology and presentations of eating and mealtime behavioral abnormalities in ASD from infancy to adolescence. Abnormalities in breastfeeding and acceptance of complementary foods have been described by most of the studies evaluating ASD early feeding history. Among the various eating and mealtime behaviors identified in ASD children and adolescents, the most common was food selectivity. The present review also provides brief overviews of the various aspects of food that may influence food acceptance by ASD patients and of the correlation between eating problems and ASD core symptoms, as well as with cognitive level, language skills, and family environment. However, studies evaluating eating problems in ASD children and adolescents are very heterogeneous and they show methodological differences. Moreover, the absence of unique definitions of eating and mealtime behaviors in ASD further limits the comparability of studies.
Keywords: autism spectrum disorder, feeding, infancy, childhood, adolescence
Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by impaired social and communication skills and repetitive and restrictive behaviors.1 According to data collected by the Center for Diseases Control and Prevention (CDC) of Atlanta, ASD prevalence amounted to 1–2% during 2014 in the USA, with an estimated male–female ratio of 4:1.2
In addition to core symptoms, ASD clinical features also include aberrant eating behaviors. Although some types of eating disturbances, such as food refusal, are also frequent in the general pediatric population, their prevalence appears to be significantly higher in ASD children,3 with percentages ranging from 51% to 89%.4–10
The origin of eating abnormalities in ASD children is believed to be multifactorial, including behavioral, cognitive, and environmental causes.11 In particular, among the behavioral factors that can condition eating behaviors, there are the symptoms of repetitiveness and rituals, including fear of novelty, inflexibility, need for sameness, but also hypo or hyper-reactivity to sensory stimuli. The alteration of the sensory processing described in ASD patients12 may, in fact, make mealtime challenging for ASD individuals, given the high rate of stimulus coming from food and environment during mealtime.
Feeding difficulties can influence the health status of the child and represent a source of concern and stress for parents. Thus, a better knowledge of eating abnormalities in ASD is desirable in order to widen the evidence base for treatment that is necessary to open new avenues for the most effective intervention strategies.
On this basis, the purpose of the present review is to update the main current knowledge about epidemiology and presentations of eating and mealtime behavioral abnormalities in ASD individuals from infancy to adolescence.
Materials and Methods
A web-based review of the literature was performed to identify all studies reporting on clinical features of eating problems (EP) in ASD children and adolescents. A narrative review format was chosen.
The search strategy was originally created and was conducted in the PUBMED database,SCOPUS database, COCHRANE LIBRARY database, and PUBPSYCH database. The following keywords were used: “eating,” “feeding,” “food selectivity,” “mealtime,” “diet,” AND “autism.” Additional articles were manually identified by reviewing article references. Inclusion criteria were: (a) original articles published between January 2010 and December 2019; (b) report of any data regarding clinical features of eating behavior in ASD people; (c) papers directly focused on children and adolescents; (d) English language; (e) sample size greater than 15 participants. We excluded: (a) review, meta-analysis articles, book chapters, or case report/case series articles; (b) papers in which participants did not receive a full diagnosis of ASD (ie, with “autistic traits”); (c) studies dealing with eating disorders identified with distinct diagnosis as anorexia nervosa or bulimia nervosa; (d) studies conducted on animal models; (e) articles referred to specific genetic mutations or syndromes. The resulting narrative review includes two sections. The first section presents evidence on early feeding history in ASD patients, in particular: breastfeeding, weaning, and addition of complementary foods. The second section focuses on the most common eating and mealtime behaviors identified in ASD children and adolescents.
The primary literature search, conducted in May 2020, identified 4310 records from four databases. After removing duplicates between databases, we operated a first screening based on abstracts. Then, 116 full texts were read and analyzed for eligibility by two authors independently. Any disagreement was resolved through discussion. According to the inclusion/exclusion criteria, 60 articles were excluded, and 56 original articles were retained for the final analysis. Three additional studies were identified in the course of the bibliographical analysis. The current review includes a total of 59 papers. A flow diagram of the screening process can be seen in Figure 1.
Figure 1 Flow diagram of the screening procedure.
Study features are summarized in Table 1.
Table 1 Studies’ Features
We found thirty-one case–control studies and twenty-eight cross-sectional studies. The age of ASD participants ranged from 9 months to 18 years.
In fifty papers, which enrolled both males and females, a major prevalence of males was found. In four papers, the exact male:female ratio is not indicated. Two studies had an exclusively male sample, and two other studies an only female sample.
ASD was diagnosed according to the Diagnostic and Statistical Manual of Mental Disorder (DSM) or International Statistical Classification of Diseases (ICD) criteria in thirty studies. The others did not specify the diagnostic psychiatric classification system used to establish an ASD diagnosis.
ASD sample sizes ranged from 18 to 1747 participants. When present, the control group size ranged from 22 to 37,510 and it included: 1) typically developing (TD) subjects in fifteen studies; 2) subjects without an ASD diagnosis (called “non-ASD”) in four cases; 3) population-based controls in three cases; 4) children diagnosed with other neurodevelopmental disorders in two cases; 5) siblings in one study; 6) mix of the precedents in five studies.
Eating behaviors were assessed through a standardized instrument in thirty-five works. The most common of them were the Brief Autism Mealtime Behavior Inventory (BAMBI),13 used by eleven researchers’ teams, and the Food Frequency Questionnaire (FFQ),14 used by seven teams. Other standardized instruments were used in the remaining studies.
Feeding History During Infancy
Table 2 Studies’ Results
Most of the studies showed some quantitative abnormalities of breastfeeding, such as low breastfeeding rate, short duration, and late initiation of breastfeeding.
In more detail, breastfeeding prevalence in ASD amounted to values between 70% and 85%,15,16 which decreased to values between 20% and 76% when an exclusive assumption of breast milk was considered.17,19,20 Furthermore, the percentage of ASD children who had been breastfed for at least six months was estimated between 19% and 26%.20,21,25
Five studies compared breastfeeding rates between ASD children and non-ASD children.16,17,21,23,25 Two studies, among which a recent paper with major statistical and epidemiological power resulting from the adjustment for a long series of confounding factors,21 found that ASD children showed lower exclusive breastfeeding rates.17,21 Conversely, three studies found no differences.16,23,25
Six studies compared the breastfeeding length between the ASD population and healthy controls.19,21,22,24,25,28 Only in two studies was a similar length found,25,28 while four studies found a shorter duration in the ASD population.19,21,22,24 Conversely, ASD patients showed a higher breastfeeding duration in comparison with Attention Deficit Hyperactivity Disorder (ADHD) children.28
Only one paper presented data on the starting time of assumption of breast milk in the ASD population, identifying a later breastfeeding initiation compared to non-ASD children.22
One study investigated the relationship between the lack of breastfeeding and autism symptom severity, and they found no association.19
Four studies examined the qualitative aspects of breastfeeding.15,18,26,29 The most common difficulties were related to atypical sucking features: continuous, unorganized sucking,29 or vigorous sucking, not stopping with satiation.26 Other breastfeeding patterns, recognized in ASD children, were characterized by frequent breaks, fidgety, and frequent requests of feeding.18 Only one study compared qualitative breastfeeding abnormalities between ASD and TD children, finding no significant differences, likely due to its small sample size.15
Weaning and Transition to Solid Foods
Only three studies presented data on weaning or transition to solid foods.16,20,27 It has been described that 60.9% of ASD children received weaning before the sixth month of life.20 No differences in the age of transition from liquids to pureed foods have been identified between ASD and TD.27 Some problems with the progression from smooth purée to more textured foods20 or in the timing of the acceptance of solid food16 have been recognized. A delay in drinking from a cup and in feeding themselves using a fork was found in ASD children.27
Eating and Mealtime Behaviors in Childhood and Adolescence
Fifty-one studies evaluated eating and mealtime behaviors in ASD children and adolescents (Table 2).
EP Epidemiology and Presentations
ASD children showed a high prevalence of EP, with reported values between 43.6% and 96%.18,30–36 Their prevalence was found to be higher in ASD children compared to TD children,32,37,38 to siblings,39,40 and to children with other developmental disorders, such as ADHD,36 intellectual disability,31 and language delay.34
Among feeding abnormal patterns that could be found in ASD people during childhood, the most frequent is food selectivity (FS)17,35,41–43 which in turn includes more or less severe limitations in food acceptance. The prevalence of FS among ASD children and adolescents was extremely different among studies, with fluctuation between 9.8% and 83%.17,20,33,34,36,34,42–49 Most studies found a higher prevalence of FS in ASD children compared with TD controls.17,32,36,4050–56 However, one study found that a difference between ASD and TD children exists only when considering severe eating selectiveness, while no difference emerged about EP of mild severity.41
Other atypical eating behaviors have been identified in a child or adolescent with ASD, such as eating too little or too much,42 difficulty in remaining seated at the table all mealtime long,18,33,49 inflexibility about mealtime routines,33,43,49 ie, requesting of food prepared in a specific way,18 gagging15,18 closing the mouth tightly,33,49 aggressive or disruptive behaviors during mealtime,31,33,43,49 eating non-food items or “pica,”15,16,36 and pocketing food without swallowing.36
EP in ASD children represented one common reason for parental concern,15,32,39,57–60 that progressively increased during the first year of life of the child.15 Evidence, in fact, suggested that EP are particularly common during early childhood in ASD children,61 then, in most cases, they tend to improve with age.18,31,35,36,62
In detail, there are some eating behaviors which appeared to be more common during early childhood in ASD children, such as playing with food, eating very slowly, craving certain food, requiring food to be prepared in a special way, stuffing mouth or cheeks, gagging, leaving the table,18 eating in some mealtime locations.15,18 On the other hand, there are few behaviors that seem to remain stable across childhood and adolescence, such as “having some food preferences” or “repetitive eating of certain foods.”18
Similarly, one study found that FS prevalence and severity remained stable in a group of ASD children longitudinally evaluated after a two-year period.63 However, other researchers found an increase of selectiveness over time,16,55 while still other authors found a decline in FS symptom severity54 and prevalence with the growth of the child.35
EP and Neuropsychological Features
The presence of cognitive impairment did not correlate with the presence or the severity of EP in ASD children.36,62,64,65 When focusing on high-functioning ASD individuals, it seems that the lower the intelligence quotient (IQ) the more severe the eating disturbance.66 In particular, the association between cognitive performance and the presence of eating disturbances was evaluated within a group of high-functioning ASD girls (IQ>70), finding an inverse association between the full-scale IQ score and girls’ self-rated abnormal eating behaviors. Studies considering the correlation between cognitive level and the presence of FS achieved contrasting results. In fact, comparing cognitive level between selective and non-selective children, one study found lower cognitive abilities in subjects with FS,67 while two studies did not identify any significant difference.44,45
Moreover, a higher prevalence of EP was found in children with lower expressive language skills.30
Using parental reports, four studies found that the presence of EP in ASD children was associated with a major severity of ASD symptoms,31,35,39,44 while only one study, conducted on a small sample of selective ASD children, found no association between FS and parental reports of autism symptom severity.59 Using professional assessment based on the direct observation of the child, only one study found major autism severity in selective ASD children,67 while two studies, characterized by larger samples, found no association.44,45 Some authors found no association between EP and social communication and interaction impairment severity,65,68 while an association with repetitive and restrictive behaviors was identified.45,65,68
Some studies recognized internalizing/externalizing behaviors in ASD patients with EP, in particular when the eating disturbance is more severe,45,65,67 although one study achieved contrasting results.69
The study of adaptive skills did not reveal significant differences between ASD individuals with or without EP,62,67 even if scarcer daily life skills have been found in ASD individuals with FS,44 with food neophobia70 or with a moderate and declining subtype of EP.62
EP and Behavioral and Environmental Factors
Authors have identified a series of factors that could influence the FS of ASD children. Various behaviors in children could worsen FS, such as sipping more, playing, talking, or being away from the table during the meal.71 One study revealed that ASD children were more likely to refuse foods on the basis of their features than TD controls.52 Food acceptance by ASD children could be influenced by various aspects of food such as its texture, consistency, color, temperature, smell, taste, but also presentation, brand, shape, or food mixed together.15,25,29,34–36,52,59,67,71 Prospective research has shown that ASD subjects, after the transition from childhood to adolescence, exhibited a reduction of food refusal based on texture and mixture.57 Furthermore, some studies reported that there were no differences between ASD and TD regarding color-based food refusal.32,52 Many studies have identified an association between sensory measures (assessed using the Sensory Profile scale72) and EP in ASD children,27,31,37,38,40,63,65,73–75 while this association was not significant according to only two studies.68,69
The strategies adopted by parents to cope with their children’s FS are extremely different. One study reported that direct commands to eat from parents are more effective than other less directive strategies (trying to coax the child, giving additional commands, verbalizations) on inducing the child to take a bite of unfamiliar food.71 Parents often use praise or distractions, to allow the child to drink more or to eat his/her favorite food, to give rewards or, on the contrary, reprimands, and punishments.39,47
Although familial-derived food preferences have a limited effect on the FS of ASD children,39,40 mealtime behaviors and family context are suggested to be able to influence each other. On the one hand, parents’ behaviors may be important in directing the child’s diet in a healthy direction.29 On the other hand, the presence of disruptive behaviors of the child during mealtime appeared to impact on life and quality of the relationship between parents.43 Whether FS is associated or not with parental stress is still debated and the two studies evaluating this association had conflicting results. One study found higher levels of parental stress in the FS group compared to the non-selective group,67 while another study showed no association between the two variables.43
Feeding History During Infancy
As well as some ASD clinical signs that may be identified during the first years of life, signs of dysregulated eating patterns may potentially be recognized early,76 when breastfeeding and weaning.
Breastfeeding abnormalities in ASD people have been suggested, but their full characterization is still an object of study. Literature has, in fact, focused both on quantitative and qualitative aspects of breastfeeding, achieving in most cases conflicting results.
According to data collected by the Centers for Disease Control and Prevention of Atlanta (www.cdc.gov/breastfeeding/data/nis_data/index.htm), breastfeeding rate in the general population of the United States amounted on increasing values from 76% to 83% over the period 2009–2016, while the percentage of children being exclusively breastfed for six months has gone from 15% to 25% over the same period.
Similarly, recent studies included in this review estimated an analogous prevalence of breastfeeding and of exclusive breastfeeding for at least six months in the ASD population.
However, even if studies comparing breastfeeding rates and duration between ASD children and controls actually found conflicting results, according to a recent big meta-analysis, in which seven articles were included, ASD subjects (N=1463) were significantly less likely to have been breastfed than children without ASD (N=1180) (p<0.002).77 In addition to these quantitative aspects, qualitative breastfeeding abnormalities in the ASD population have also been highlighted in the literature.
Although the data are conflicting, taken together, evidence supports the hypothesis of an association between breastfeeding features and ASD. The nature of the association between dysregulated breastfeeding and ASD is not well known. Breastfeeding pattern and duration are a result of the complex mother–child interaction, which is in turn determined both by the mother’s characteristics and behaviors, and by child-related features (such as gestational age, health status, and neurodevelopmental system).26 Consequently, according to some authors, breastfeeding abnormalities may represent an early clinical sign of ASD, intrinsic of the child. As an example, the “continuous sucking” pattern, which is one of the most frequent atypical breastfeeding patterns in ASD, may be considered as a persistent repetitive behavior of the newborn.26 However, it is interesting to note that evidence on how much the dysregulated breastfeeding pattern represents an early clinical concern for parents and a reason for request of specialist consultation are inconclusive.
On the other hand, some authors suggested an etiopathogenetic link between breastfeeding and ASD. It is well known, in fact, that both genetics and the environmental factors play a role in the occurrence of ASD. Among environmental factors, optimal breastfeeding (defined as exclusive breastfeeding longer than 6 months according to World Health Organization recommendations78) has been suggested as protection against ASD in vulnerable children.19,22,77 If confirmed, its protective role may be explained by the peculiar and irreproducible composition of breast milk;79 in particular, it has been suggested that oxytocin, polyunsaturated fatty acids,80,81 but also Lactobacillus and Bifidobacterium contained in breast milk, may play a potential role in improving the neurodevelopmental outcome of the newborn.82–84
Most studies on breastfeeding features in the ASD population are based on parental reports, associated with a potential intrinsic recall bias, or retrospective analyses, which do not allow researchers to draw conclusions on the causality of a possible association. For this reason, further prospective longitudinal research with rigorous methodology is required to explore whether breastfeeding may have a potential pathophysiological role on the occurrence of ASD.
Evidence about the relationship between breastfeeding abnormalities and later EP development in ASD patients is very scarce. Gray et al, through a retrospective analysis of early feeding history in three groups of ASD children stratified according to age ranges, found that the “early childhood” group (2–6 years), compared to the “mid-childhood” and the “adolescents” groups, showed the highest prevalence of both past breastfeeding abnormalities and current EP.18 However, this finding is not sufficient to establish whether breastfeeding abnormalities may be a prelude to later EP. Thus, prospective studies on this topic are needed for a better understanding of breastfeeding abnormalities’ predictive power of EP.
In any case, given that several benefits of breastfeeding in the general population have been described, health-care professionals should continue to encourage mothers to breastfeed their infants for at least 6 months.
Weaning and Transition to Solid Foods
About weaning timing and transition to solid foods in the ASD population, there are little available data. According to WHO guidelines, caregivers should start to feed infants with complementary foods at six months,85 while an earlier introduction of solids may give some benefits related to the development of food allergies, but evidence on this topic is still discordant.86,87
Data available for the ASD population suggest a similar weaning timing to that of the general pediatric population,20 while ASD children presented a delayed acceptance of textured foods and a delayed use of glasses and cutlery. As for breastfeeding, difficulties in the later acceptance of solids may be considered as early signs of ASD, in particular as early clinical presentations of the typical sameness, inflexibility, and fear of novelty in ASD children.16 Given the exiguity of available data on this matter, whether weaning-related difficulties may have a place among early predictive factors of ASD has still to be clarified. Slow learning to use cups and forks use could be framed in the general developmental delay, including for motor skills, that can be identified in many ASD children. However, it is important to note that, according to our knowledge, the link between early feeding difficulties and successive development of eating issues, ie, FS, has not been examined. Consequently, this could represent a future direction of research.
Eating and Mealtime Behaviors in Childhood and Adolescence
EP Epidemiology and Presentations
Broadly defined, eating and feeding disturbances are relatively common among TD children, as a result of several contributing factors, both individual and environmental.88 Their prevalence in the general pediatric population is approximately 25–45%.88,89 A similar prevalence has been identified among children with different types of neurological impairments.90
In accordance with previous literature,91 recent studies have shown asignificantly higher prevalence of eating and feeding abnormalities among ASD children and adolescents.
In fact, a broad range of prevalence estimates has been identified, probably due to the lack of a universally accepted definition of feeding problems. The term feeding/eating disturbances includes a group of extremely heterogeneous clinical phenotypes, which may include abnormalities in the development of eating skills, difficulty in managing some foods, refusal of some food categories, lack of interest in food, or utilization of food as a comforter.88
Actually, in ASD patients several kinds of eating and mealtime behavioral disturbances have been recognized, among which, in accordance with previous literature, FS was reported as the most common.11 For FS a shared definition, as well as systematic criteria and approaches to identify it, are missing, making it difficult to compare literature results on the topic. The lack of a unique definition of FS is related to the amplitude of the concept. It represents, in fact, an umbrella term which covers multiple eating behaviors, as if they were different shades of one color, including picky eating, ie, a choosy approach to food,92 food refusal, ie, the refusal to eat all of most foods,93 FN, ie, the propensity to refuse to try unfamiliar food,56 limited food repertoire, ie, a limited variety of accepted food categories,94 repetitive eating pattern, ie, the propensity to always eat the same foods.95
Another reason for the huge variability of EP prevalence in ASD patients can be found in the sampling and methodological differences among studies. Size, demographical features, and clinical characterization of the enrolled sample change from one study to another. This aspect becomes of great relevance if we consider, for example, that eating profiles have been suggested to be different between males and females56 or according to age.18 Differently from TD children, in which early feeding difficulties are often transient and resolve spontaneously,88 eating disturbances in ASD subjects are frequently detectable from infancy to adulthood, with prevalence changing according to the considered age group. In particular, most studies suggested a decline of prevalence of EP over time, and an improvement of dietary habits with the growth. In reality, this data could be partly due to a change over time of parental perception of their child’s eating, as children become more and more independent in their feeding and, simultaneously, parents progressively feed their children with their favorite food.18
In reality, a full description of EP changes from childhood to adolescence and, consequently, a detailed comparison among EP in different stages of pediatric age are not currently possible since the most of published papers on this topic cover a wide age range of their sample. Further prospective studies with a clear stratification of the sample according to age groups are desirable in order to better characterize the developmental trajectories of EP in ASD individuals, also considering that EP can impact on the health status of the child. Atypical eating patterns have been, in fact, considered as a risk factor for abnormalities in body weight41,96,97 and in nutritional intake41,98 in ASD patients.
EP and Neuropsychological Factors
Findings about the association between eating abnormalities and some clinical features of ASD patients, as cognitive and language impairment, are still discordant.
Poorer daily living skills and more severe autism symptoms in ASD individuals with EP have often been identified through parents’ reports. However, when a professional assessment on a child’s functioning and symptoms was carried out, this association was not confirmed. A possible explanation for this discordance may be found in the negative impact that EP has on daily family life and on parents’ perception of child functioning. Consequently, during the assessment, parents described their children’s adaptive skills and autism symptoms as worse than they really are.
EP and Behavioral and Environmental Factors
Studies6,99–101 show that ASD patients are more likely to refuse food on the basis of several of their sensorial features, but, contrary to expectations, not based on color, although literature on this aspect is still discordant.99,102–104
Studies have consistently shown that eating disturbances in the ASD population are associated with higher SP scores. Thus, eating difficulties could be considered a consequence of sensory hypersensitivity, since the act of eating involves multiple senses as vision, touch, taste, and smell.
Moreover, sensory abnormalities in ASD individuals are very frequent, with a prevalence amounting on 70–95%, and they may manifest themselves as hyper- or over-responsivity, under-responsivity, or sensory seeking.105 Hyperresponsivity is suggested to be the most common pattern in ASD patients.105 Furthermore, some evidence revealed that ASD individuals have a great frequency of sensory abnormalities, in particular in the domains of taste and smell.106,107 In this context, mealtime, made of changeable combinations of various sensorial stimuli, may represent a challenging experience for ASD individuals.
A link between a narrow diet and repetitive/ritualistic behaviors has been identified, suggesting that EP could be considered an extension of the features of rigidity and inflexibility, that are a hallmark of ASD people.6,93 However, whether mealtime disturbances, repetitive behaviors, and sensory hypersensitivity may represent a cluster of symptoms often seen together is yet not well defined.
Some children’s or parents’ mealtime behaviors can influence what/how much/how the child eats, as previously reported in the literature.93 In fact, a vicious cycle is often installed when parents allow children to choose how and what to eat, reinforcing their abnormal eating patterns. However, EP in ASD children is likely to be not due to their parents’ behaviors, since studies comparing ASD children and their siblings found different eating and mealtime behavioral patterns.
Although some eating difficulties are related to intrinsic features of ASD, new eating habits may be introduced in the presence of an adequate environmental stimulus.29 Whether EP of ASD children may be considered the main cause of parental stress is still debated. Anyway, it is evident that educational programs for parents, including instructions on strategies to be adopted in order to reduce the occurrence of EP, are recommended.
EP in ASD children and adolescents represents a concern for parents and a potential cause of health issues. However, studies are very heterogeneous, showing methodological differences, so their results are difficult to compare. In addition, the absence of unique definitions of EP in ASD further limits the comparability of studies.
The current knowledge does not allow us to draw conclusions on the predictive power of eating disturbances when recognized in early childhood. Consequently, establishing the role of eating and mealtime behavior abnormalities as an early marker of ASD may be a future direction of research.
Future investigations on the implications of the behavioral profile, cognitive impairment, ASD severity, age, and sex on feeding and mealtime behaviors are needed, to better understand mechanisms beyond eating difficulties and to provide additional information useful to develop the most efficient intervention strategies for EP.
The authors report no conflicts of interest in this work.
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