Some research has linked autism to bowel problems. Researchers at the Centre for Child and Adolescent Health in Bristol studied 78 children with autism and compared them to 12,906 unaffected children. Over the first 3.5 years of life there were no major differences between the groups in stool colour and consistency, diaorrhea and constipation, and stomach pain. Some of the autistic children had more stools per day at 30 months but the researchers thought that this "may be a secondary phenomenon related to differences in diet." The researchers also noted that some of the older children with autism did have bowel problems. Dr Alan Emonds who led the research said "it is not clear whether these symptoms are due to dietary changes or abnormalities in intestinal function associated with autism."
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