Association between Autism Spectrum Disorder and Food Allergy: A Systematic Review and Meta‐analysis

Exploring Dietary Interventions in Autism Spectrum Disorder

Autism spectrum disorder (ASD) involves social communication difficulties and repetitive behaviors, and it has a growing prevalence worldwide. Symptoms include cognitive impairments, gastrointestinal (GI) issues, feeding difficulties, and psychological problems. A significant concern in ASD is food selectivity, leading to nutrient deficiencies. Common GI issues in ASD, such as constipation and irritable bowel syndrome, stem from abnormal gut flora and immune system dysregulation. Sensory sensitivities and behavioral challenges exacerbate these problems, correlating with neurological symptom severity. Children with ASD also exhibit higher oxidative stress due to low antioxidant levels like glutathione. Therapeutic diets, including ketogenic, high-antioxidant, gluten-free and casein-free, and probiotic-rich diets, show potential in managing ASD symptoms like behavior, communication, GI issues, and oxidative stress, though the evidence is limited. Various studies have focused on different populations, but there is increasing concern about the impact among children. This review aims to highlight the food preferences of the ASD population, analyze the effect of the physicochemical and nutritional properties of foods on the selectivity in its consumption, GI problems, and antioxidant deficiencies in individuals with ASD, and evaluate the effectiveness of therapeutic diets, including diets rich in antioxidants, gluten-free and casein-free, ketogenic and essential fatty acids, and probiotic-rich diets in managing these challenges.

Associations between autistic and comorbid somatic problems of gastrointestinal disorders, food allergy, pain, and fatigue in adults

LAY ABSTRACT

What is already known about the topic?Autistic children frequently often have accompanying physical health problems. However, this has been much less studied in autistic men and women during adulthood.What does this article add?This is one of the first studies to investigate the associations between autistic and somatic problems in adults from the general population. Using a continuous measure of autistic symptom scores and a categorical definition of autism (referred to below as probable autism) which considered symptom severity, childhood age of onset, and functional impairment, we found that autistic problems and irritable bowel syndrome, food allergy, pain, and fatigue were associated in adults. Sex differences were present for pain and fatigue, for which the associations with autistic symptom scores were somewhat stronger in females than males. Regarding age differences, the associations with fatigue and having food allergy were more pronounced in younger adults. Conversely, older individuals had a higher risk of developing irritable bowel syndrome or experiencing pain if they met the criteria for probable autism.Implications for practice, research, or policyThere is a need for providing routine programs of screening, assessment, and treatment of autism-related somatic problems and developing evidence-based interventions for autistic individuals. These could be tailored to the needs of specific autistic populations. For example, autistic females could be given extra attention about the potential presence of pain and fatigue, younger adults about the potential presence of food allergy and fatigue, and older adults concerning the potential presence of irritable bowel syndrome and pain.

Early childhood neurodevelopmental milestones in children with allergic diseases: the Japan Environment and Children's Study (JECS)

This study investigated the potential link between early childhood allergic diseases and neurodevelopmental milestone attainment during the first 3 years of life. Utilizing data from a large-scale prospective birth cohort study in Japan, encompassing 87,986 children, we examined physician-diagnosed and caregiver-reported allergic conditions, including atopic dermatitis (AD), asthma, and food allergy (FA). Neurodevelopmental milestones were assessed using the Ages and Stages Questionnaires at 1, 1.5, 2, 2.5, and 3 years of age. Stabilized inverse probability-weighted generalized estimating equation models were employed to estimate odds ratios (ORs). Our analysis revealed no significant association of AD and asthma with delay in communication, gross motor, fine motor, problem-solving, and personal-social skills during the initial 3 years of life. However, children with FA showed an increased likelihood of experiencing gross motor delay compared with that shown by those without FA (weighted adjusted OR: 1.14). Despite this, no significant association of FA with other developmental domains was observed. Early childhood allergies may not influence neurodevelopmental delays. However, there is a potential association between FA and delays, specifically in gross motor skills, that warrants routine developmental monitoring and additional investigations.

Associations between mental and physical conditions in children and adolescents: An umbrella review

We mapped the evidence on the type and strength of associations between a broad range of mental and physical conditions in children and adolescents, by carrying out an umbrella review, i.e., a quantitative synthesis of previous systematic reviews and meta-analyses. We also assessed to which extent the links between mental and physical conditions vary across disorders or, by contrast, are transdiagnostic. Based on a pre-established protocol, we retained 45 systematic reviews/meta-analyses, encompassing around 12.5 million of participants. In analyses limited to the most rigorous estimates, we found evidence for the following associations: ADHD-asthma, ADHD-obesity, and depression-asthma. A transdiagnostic association was confirmed between asthma and anxiety/ASD/depression/bipolar disorder, between obesity and ADHD/ASD/depression, and between dermatitis and ASD/ADHD. We conclude that obesity and allergic conditions are likely to be associated with mental disorders in children and adolescents. Our results can help clinicians explore potential links between mental and physical conditions in children/adolescent and provide a road map for future studies aimed at shading light on the underlying factors.