On Nutrition by Ed Blonz

Food-Behavior Connections Difficult to Prove

DEAR DR. BLONZ: Hyperactivity and behavioral issues in children are often thought -- by parents, staff and some health professionals -- to be associated with certain foods. However, there has been no clear clinical evidence that food causes behavioral issues in children. I work with children as a registered dietitian in a psychiatric facility, and am interested in your comments. -- S.F., Phoenix

DEAR S.F.: You have my respect and admiration for your work in this important area. There is no question that food allergies exist, but attributing food allergies with childhood behavior issues remains controversial. That said, it is not unreasonable to at least consider foods as a possibility if other avenues have been unproductive.

It is essential to proceed cautiously, reviewing patient history and calling upon a clinician experienced in this area. Consider that connections between behaviors and offending substances do not always display in a manner that makes it easy to connect the dots. You want to avoid placing the blame on the wrong substances without evidence. Jumping to conclusions can change parental behavior, which then gets learned by -- or should I say foisted upon -- their child in the form of statements like, “You shouldn’t eat that; it will make you sick.” All this can become a march down an unproductive path with ever-growing limits placed on the child’s ability to eat and enjoy their life.

The ironic thing is that a parent might observe improvements in their child’s behavior even if the wrong substance is identified. It might be a case of the child “growing out” of the problem during the “treatment period,” and the dietary switch getting the credit. Improvements can also take place because they are expected; this is the essence of the placebo effect. If the underlying problem was not food-allergy-related, though, it could remain. If the symptoms resurface at a later date, other foods or food categories might get added to the “banned” list, further restricting the child and the parents.

This is only a scenario, but I bring it up because it highlights the importance of an accurate diagnosis. The parents can assist the process by maintaining a log of foods consumed and reactions observed, and this can aid a trained health professional in compiling the likely foods for further testing.

Once nutritional “suspects” are identified, testing in a controlled clinical environment is essential to remove any possible bias from all concerned parties. The gold standard is the double-blind, placebo-controlled food challenge.

Keep in mind that 60% to 80% of children with allergies to milk or egg outgrow them by age 16, which suggests a need for repeat allergy testing as a child ages. I would encourage you to discuss this with your patients’ parents and the physicians on staff.

Send questions to: “On Nutrition,” Ed Blonz, c/o Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO, 64106. Send email inquiries to questions@blonz.com. Due to the volume of mail, personal replies cannot be provided.