A very quick post to bring to your attention a recently published paper which has just started to make an impact on various social media. The paper is by Pennesi and Cousino Klein* and reports on a survey of parent responses on the efficacy of using a gluten- and casein-free diet with their children with autism. The press release accompanying the paper is here.
At the moment I don't have the full-text so can't really add more than what information is currently available and so will probably end up posting again about this paper. Yes, it is data based on an on-line survey; yes, it exclusively relies on parent - primary caregiver report and so yes it is not by any means gold-standard when it comes to methodological quality. I will perhaps apologise for the 'parent - primary caregiver' bit and the implication that somehow theirs is not an important voice. It is, and potential bias aside, certainly when you look at the history of GFCF diets and autism, it was parents who made the first observations about a possible effect, so I feel a bit of respect is due.
Perhaps carrying a degree of bias myself about such work (here), I'd like to think that there are things that can be learned from this study as there are in all studies; if only where to start channelling a little more research time and effort to further inform the science in this area.
* Pennesi CM. & Cousino Klein L. Effectiveness of the gluten-free, casein-free diet for children diagnosed with autism spectrum disorder: Based on parental report. Nutritional Neuroscience. February 2012.
DOI: 10.1179/1476830512Y.0000000003
You are what you eat. Will a casien gluten free diet help all children with autism? Probably not but it may help many children. PKU is an inborn metabolic error that is associated with intellectual disability and in some cases with autism. All newborns are now screened for PKU and when a positive result occurs the infant is immediately placed on a phenylaline free diet.
ReplyDeleteShould all autistic children be placed on a phenylalnine free diet? Certainly not, but PKU is a window on how diet can effect brain development and changes in diet may help in conditions like celiac disease or other unrecognized causes of human disease.
I tried a casein free gluten free diet with my daughter but it didn't appear to help at all but there was no side effects when I tried it and there is no evidence that trying a casein and gluten free diet has any harmful effects.
Thanks RAJ.
ReplyDeleteI'm glad you brought up the PKU analogy because it is an important one which introduces the possibility that (a) diet might be able to affect mental as well as physical health and wellbeing and (b) a subgroup of people with an autism spectrum condition might also have some kind of 'inborn error of metabolism' with regards to gluten and casein - whether for example just gluten or more generically related to carbs as per the Williams research: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0024585
Certainly there is some emerging evidence to suggest that children with autism can and do present with a lactose intolerance as per the trial by Kushak and colleagues which I covered last year: http://questioning-answers.blogspot.com/2011/03/enzyme-activity-milk-and-autism.html and autism is no stranger to the possibility of underlying coeliac (celiac) disease being related: http://www.ncbi.nlm.nih.gov/pubmed/19564647 with an estimated 3% of cases showing a connection: http://www.springerlink.com/content/c6535100501773wu/
Outside of these issues, the recent opinion piece looking at the classification of gluten sensitivity outside of just coeliac disease might also come into play: http://www.biomedcentral.com/1741-7015/10/13
The onus is surely now on autism research and practice to start asking some serious questions about (i) why diet seems to show effects for some children, (ii) is it possible to identify best- and non-responders similar to PKU and the Guthrie heel prick test (which by the way would seem to be a goldmine of information waiting to be trawled) and (iii) irrespective of the whys, supporting children/adults who use diet rather than simply passing the whole thing off as some kind of 'fad'
What I liked about this study is not the "whether the diet works in autism or not" approach, but rather "who is most likely to respond to a diet". I think it would make it easier for doctors to understand the diet with these criteria, since they make sense why a diet response might work.
ReplyDeleteI would love to see the SCD mentioned along side gfcf more. My son was a miracle diet responder but we had no response at all to the gfcf, even though he has gluten issues. Maybe that will be the next step...who would be a possible diet responder and which diet might be likely to work (long time off, I know, just wishing).
Thanks Mrs Ed.
ReplyDeleteI agree that the science has probably now moved to a point where asking the general question: does diet work - has perhaps been replaced by 'who' it works for and then, why.
Just late this afternoon (UK time) I managed to get a hold of then full-text of the paper and so will have a good look through it in the coming days.
I think the Williams paper last year firmly put carbs on the research menu. I suppose even us die-hard GFCF proponents have to accept that we could be looking at a much wider issue here outside of those cases where coeliac disease/gluten sensitivity is part of the story.