The Lactose Intolerance Clearinghouse Has Moved.

My old website can be found at www.stevecarper.com/li I am no longer updating the site, so there will be dead links. The static information provided by me is still sound.

For quick offline reference, you can purchase Planet Lactose: The Best of the Blog as an ebook on Smashwords.com or Amazon.com or BarnesandNoble.com or a whole lot of other places that Smashwords is suppose to distribute the book to. Almost 100,000 words on LI, allergies, milk products, milk-free products, and the genetics of intolerance, along with large helpings of the weirdness that is the Net.

I suffer the universal malady of spam and adbots, so I moderate comments here. That may mean you'll see a long lag before I remember to check the site and approve them. Despite the gap, you'll always get your say. I read every single one, and every legitimate one gets posted.


Tuesday, August 25, 2009

Science Doesn't Know. And That's a Good Thing.

A major review study was just published in the Journal of Paediatrics and Child Health, Management of cow's milk protein allergy in infants and young children: An expert panel perspective by Katrina J. Allen et al.

ABSTRACT
Cow's milk protein allergy is a condition commonly managed by general practitioners and paediatricians. The diagnosis is usually made in the first 12 months of life. Management of immediate allergic reactions and anaphylaxis includes the prevention of accidental food ingestion and provision of an adrenaline autoinjector, if appropriate. By contrast, the clinical course of delayed food-allergic manifestations is characterised by chronicity, and is often associated with nutritional or behavioural sequelae. Correct diagnosis of these non-IgE-mediated conditions may be delayed due to a lack of reliable diagnostic markers. This review aims to guide clinicians in the: (i) diagnostic evaluation (skin prick testing or measurement of food-specific serum IgE levels; indications for diagnostic challenges for suspected IgE- and non-IgE-mediated food allergy), (ii) dietary treatment, (iii) assessment of response to treatment, (iv) differential diagnosis and further diagnostic work-up in non-responders, (v) follow-up assessment of tolerance development and (vi) recommendations for further referral.

In short, while true food allergies, those mediates by the IgE antibody, can be relatively easily identified by testing and managed by removing the offending food, a different and assorted set of reactions that use pathways in the body other than IgE are much harder to pin down. The symptoms come late and are hard to match up with particular foods, the tests are uncertain, removal of the food doesn't always give immediate relief.

An article on the study by Michael Woodhead also says that "is still controversy about the role of cow’s milk in infant colic and constipation."

This is part of the reality of scientific medicine. Cause and effect are hard to put together. What happens in one person is not a reliable guide to what happens in another. Large numbers of reactions are needed to put together correlations, and even when that is accomplished the problem of what is occurring in a specific individual may still not be resolvable.

Understandably, most people don't want to hear this. They want certainty. They want a doctor to tell them what is wrong and how to fix it. This anxiety multiplies when children are the ones with conditions, children who cannot properly describe their symptoms and lack any understanding about their bodies.

Often, these parents go nuts.

Like parents of autistic children. They are the current poster children, to use an unfortunate but apt metaphor, for not getting it. I wrote last month about a new study of autistic children that found that they didn't have more gastroenterological problems then other children.

I didn't begin to suggest that this study settled the issue. On the contrary, I wrote:
This is just another medical point against the need for the [GFCF] diet. Medicine is like that. One single study is not enough. Like a jigsaw puzzle, it's the cumulative picture painted by many pieces, many studies that reveals the direction medicine moves in. That picture is not yet complete.

Like every medical study of food and disease, this study had its flaws. I said every and I meant every. No study is ever large enough, representative enough, thorough enough, detailed enough. That's why a consensus must be formed from a sufficient number of studies to patch over all those holes to make a smooth road toward an answer.

Anne Dachel at Age of Autism doesn't appear to understand this. In an article Autism Experts Only Seem to Know "What Doesn't Work" she lambastes the insufficiencies of the study and the media reports that cited it.
Suddenly however, thanks to one small study in the U.S., we can forget about all this research. Rather than conclude that these new findings challenge many previous studies and more research is needed on this important issue, it seems that, in the word of Nancy Snyderman, "the findings are very conclusive."

I did find an article that mentioned the limitations of the Mayo Clinic study. In the Medpage Today story, Most GI Problems Are Not More Common in Autism (HERE), it was reported, "The study authors acknowledged some limitations of the study, including the retrospective design, use of an almost all-white population, and the failure to assess the duration, severity, and recurrence of GI symptoms."

A couple of points must be made. First and most important, new studies are found to contradict older studies all the time. That's the point of continuing the do studies. If any one study isn't sufficient and complete, more studies need to be done. And often - very, very often - the new studies show the older ones to be wrong. Your personal emotional investment in the older studies is not considered.

Second, this one new study does not end the discussion, despite what Dachel implies. Research is ongoing. Not only will other studies compare gastrointestinal problems among other groups of children, but long-term studies are taking place at this moment that will more directly look at the effectiveness of the GFCF diet.

Was this study a significant one, for all its flaws? Apparently so. Several doctors involved used it and a second study released at the same time in England to state categorically that no evidence existed that the food cures that these parents tout so heavily truly improves autistic children.

Dr. Nancy Snyderman: "The findings are very conclusive: There is no link between illness in the gut and the signs and symptoms we see in autism."

Dr. Samar H. Ibrahim: "There is actually no trial that has proven so far that a gluten-free and casein-free diet improves autism."

Dr. Alan Edmonds: "The bowel habits of young children with autistic spectrum disorder, in general, are no different from the rest of population."

Yet Dachel concludes her piece with an unthinking attack on the medical community:
There are thousands of parents who report that their kids were typical healthy children until they regressed into autism and developed gastrointestinal problems. Why wasn't there a study done looking at this particular group?

And why isn't anyone interested in looking at the kids who were severely autistic but who've make incredible gains after being on a regimen of diet and supplements?

And what about all those doctors everywhere treating autistic kids for their concomitant bowel disease? Are we to believe that they're seeing these patients for imaginary illnesses?

Thousands of anecdotal reports are not evidence. Concerned parents do not treat their children like animals in controlled laboratory conditions. They do everything in their power to help them to improve. How can they say the diet was the specific activity that helped? What about the supplements? What about the care and attention they were given? What about mere aging and development? On the flip side, what bowel disease did they have? Did the group really have an unusually high number? Were their other contributing factors? What happened in their lives, their environments, their genetics?

The best studies can barely touch on these issues because it is impossible to slice a human life into neat and non-intersecting causes. Individual cases are meaningful only to the individual. Groups often tell different stories, results that are not as certain or as favorable as the one the parent tells.

And yet, a dozen negatives may all prove to be wrong if a better positive result appears. Possibly the big studies that are awaiting completion will confirm Dasher's opinions and suspicions. Progress is certainly slower than she hopes and I emphasize with her frustration. (Remember that no studies at all on lactose intolerance are ongoing that would help explain the dozens of questions about life without lactase we still have no answers to.) I will be disappointed if those studies remain negative and her attitude does not change. At some point railing against all conventional medicine puts you in with the cranks and that route is hopeless.

The proper answer to many questions is medicine is "we don't know." Despite all the advances, the insights into genetics, the new ways to look into the body, the more delicate and sensitive tests, we still just don't know so very much. Pretending that an answer is already available but remains unseen by the legions of experts dedicating large chunks of time and effort to the problem is disheartening and dangerous. Human, though. Sad, but human.

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