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Gut Treatments- Digestive Enzymes



Gut flora, the microorganisms that live in the digestive tract of animals, produce certain necessary digestive enzymes, which are simply the enzymes that help metabolize food. However, it has been observed that some individuals on that autism spectrum have gastrointestinal (GI) tract issues, which could stem from decreased activity of digestive enzymes.42 The lack of digestive enzymes “peptides derived from gluten and casein fail to become amino acids in large numbers. Increased gut permeability then allows the peptides to leak into the blood stream, where they circulate and eventually cross the brain-blood barrier.”43 This is important because “gastrointestinal problems are common in children with ASD and may contribute to ASD behavioral symptoms.”5 Through parental surveys, the Autism Research Institute has collected parent ratings of various bio-medical interventions over the last few decades, and found that of the 2,350 parents who claimed to use digestive enzymes as part of their dietary intervention, 62% reported that their child “Got Better”.21 Parents who provide their child with digestive enzymes as part of their child’s therapy should have him/her take the digestive enzyme capsule before every meal.




A 1999 study observed the function of the upper gastrointestinal tract of 36 children on the autism spectrum. The study found that “[l]ow intestinal carbohydrate digestive enzyme activity was reported in 21 children (58.3%).”44 Additionally, 10 children in the study had decreased activity of 2 or more enzymes.44 The major drawbacks of this study are the small sample size and lack of a control group. In 2002, a study found that 49 of 90 children on the autism spectrum who underwent endoscopy to investigate their gastrointestinal problems were found to have deficiencies in one or more disaccharidase enzymes.5 Each study participant with low enzyme activity also reported having loose stools and/or gaseousness.5 A 2009 systematic review of the top 20 complementary and alternative medicines (CAMs) published in the Annals of Clinical Psychiatry awarded treatment through the use of digestive enzymes a grade D.22 A grade D signifies that there are “[t]roublingly inconsistent or inconclusive studies or studies reporting no improvements.”22



*Parents should consult their family physician before implementing any dietary intervention for their child.



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