Autism Spectrum Disorder
Autism, formally known as Autism Spectrum Disorder (ASD), is a neurodevelopmental disorder that manifests in a diverse array of challenges affecting social interaction, communication, and behaviour. The term spectrum underscores the variability in symptoms and functioning among individuals diagnosed with autism. This spectrum encompasses a broad range of abilities, disabilities, and characteristics, acknowledging that each person with autism is unique in their presentation.
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Between 2020 and 2021, data from English primary care—covering 56% of the population—indicated that 2.9% to 3% of children aged 10 to 17 had an autism diagnosis without an accompanying intellectual disability. According to the CDC, as of 2023, around 1 in 36 children in the U.S. has been diagnosed with autism. Worldwide 75 million people have autism spectrum disorder, that's 1% of the world’s population. Research from 2021 suggests 1 in 100 children worldwide are diagnosed with autism spectrum disorder. Boys are four times more likely than girls to be diagnosed with autism. Boys are also more likely to be diagnosed at an earlier age than girls, and the average age of diagnosis for boys is 4.3 years compared to 5.3 years for girls.
References
Bent, S., Bertoglio, K. and Hendren, R.L., 2009. Omega-3 fatty acids for autistic spectrum disorder: a systematic review. Journal of autism and developmental disorders, 39(8), pp.1145-1154.
Bobrowski-Khoury, N., Ramaekers, V.T., Sequeira, J.M. and Quadros, E.V., 2021. Folate receptor alpha autoantibodies in autism spectrum disorders: diagnosis, treatment and prevention. Journal of Personalized Medicine, 11(8), p.710.
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Centers for Disease Control and Prevention, 2005. National center on birth defects and developmental disabilities (ncbddd). URL: http://www. cdc. gov/ncbddd/index. Html.
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Frye, R.E., Sequeira, J.M., Quadros, E.V., James, S.J. and Rossignol, D.A., 2013. Cerebral folate receptor autoantibodies in autism spectrum disorder. Molecular psychiatry, 18(3), pp.369-381.
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Frye, R.E., Rossignol, D.A., Scahill, L., McDougle, C.J., Huberman, H. and Quadros, E.V., 2020, October. Treatment of folate metabolism abnormalities in autism spectrum disorder. In Seminars in pediatric neurology (Vol. 35, p. 100835). WB Saunders.
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​Jiang, Y., Dang, W., Sui, L., Gao, T., Kong, X., Guo, J., Liu, S., Nie, H. and Jiang, Z., 2024. Associations Between Vitamin D and Core Symptoms in ASD: An Umbrella Review. Nutrition and Dietary Supplements, pp.59-91.
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Li, Y.J., Li, Y.M. and Xiang, D.X., 2018. Supplement intervention associated with nutritional deficiencies in autism spectrum disorders: A systematic review. European journal of nutrition, 57, pp.2571-2582.​
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​LN, H., CHEN, J., LIU, L., REN, D. and JIAO, W., 2025. Vitamin B6 and Magnesium in Autism Spectrum Disorders: Potential Mechanisms and Clinical Applications. Ameri J Clin Med Re: AJCMR-215.
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​O'Nions, E., Petersen, I., Buckman, J.E., Charlton, R., Cooper, C., Corbett, A., Happé, F., Manthorpe, J., Richards, M., Saunders, R. and Zanker, C., 2023. Autism in England: assessing underdiagnosis in a population-based cohort study of prospectively collected primary care data. The Lancet Regional Health–Europe, 29.
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Pacholok, S.M., 2014. Pediatric Vitamin B12 Deficiency: When Autism Isn't Autism. Pharmacy times, 80(2).
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Richard E. Frye, Stepan Melnyk, George Fuchs, Tyra Reid, Stefanie Jernigan, Oleksandra Pavliv, Amanda Hubanks, David W. Gaylor, Laura Walters, S. Jill James. 2013 . Effectiveness of Methylcobalamin and Folinic Acid Treatment on Adaptive Behavior in Children with Autistic Disorder Is Related to Glutathione Redox Status, Autism Research and Treatment, vol. 2013 https://doi.org/10.1155/2013/609705
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Russell-Jones, G. and New, K.J., 2023. Altered neurotransmitter metabolites in vitamin B12 deficiency. J Psychiatry Psychiatr Disord, 7, pp.223-227.
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Russell-Jones, G., 2022. Functional Vitamin B12 deficiency in Autism.
Shaw, K.A., 2025. Prevalence and early identification of autism spectrum disorder among children aged 4 and 8 years—Autism and Developmental Disabilities Monitoring Network, 16 Sites, United States, 2022. MMWR. Surveillance Summaries, 74.
Wells, L., O’Hara, N., Frye, R.E., Hullavard, N. and Smith, E., 2024. Folate receptor alpha autoantibodies in the pediatric acute-onset neuropsychiatric syndrome (PANS) and pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS) population. Journal of personalized medicine, 14(2), p.166.