Data mining the ScanBrit study of a gluten- and casein-free dietary intervention for children with autism spectrum disorders: behavioural and psychometric measures of dietary response

We previously reported results based on the examination of a gluten- and casein-free diet as an intervention for children diagnosed with an autism spectrum disorder as part of the ScanBrit collaboration. Analysis based on grouped results indicated several significant differences between dietary and non-dietary participants across various core and peripheral areas of functioning. Results also indicated some disparity in individual responses to dietary modification potentially indicative of responder and non-responder differences. Further examination of the behavioural and psychometric data garnered from participants was undertaken, with a view to determining potential factors pertinent to response to dietary intervention. Participants with clinically significant scores indicative of inattention and hyperactivity behaviours and who had a significant positive changes to said scores were defined as responders to the dietary intervention. Analyses indicated several factors to be potentially pertinent to a positive response to dietary intervention in terms of symptom presentation. Chronological age was found to be the strongest predictor of response, where those participants aged between 7 and 9 years seemed to derive most benefit from dietary intervention. Further analysis based on the criteria for original study inclusion on the presence of the urine compound, trans-indolyl-3-acryloylglycine may also merit further investigation. These preliminary observations on potential best responder characteristics to a gluten- and casein-free diet for children with autism require independent replication.

The effects of a double blind, placebo controlled, artificial food colourings and benzoate preservative challenge on hyperactivity in a general population sample of preschool children

AIMS

To determine whether artificial food colourings and a preservative in the diet of 3 year old children in the general population influence hyperactive behaviour.

METHODS

A sample of 1873 children were screened in their fourth year for the presence of hyperactivity at baseline (HA), of whom 1246 had skin prick tests to identify atopy (AT). Children were selected to form the following groups: HA/AT, not-HA/AT, HA/not-AT, and not-HA/not-AT (n = 277). After baseline assessment, children were subjected to a diet eliminating artificial colourings and benzoate preservatives for one week; in the subsequent three week within subject double blind crossover study they received, in random order, periods of dietary challenge with a drink containing artificial colourings (20 mg daily) and sodium benzoate (45 mg daily) (active period), or a placebo mixture, supplementary to their diet. Behaviour was assessed by a tester blind to dietary status and by parents' ratings.

RESULTS

There were significant reductions in hyperactive behaviour during the withdrawal phase. Furthermore, there were significantly greater increases in hyperactive behaviour during the active than the placebo period based on parental reports. These effects were not influenced by the presence or absence of hyperactivity, nor by the presence or absence of atopy. There were no significant differences detected based on objective testing in the clinic.

CONCLUSIONS

There is a general adverse effect of artificial food colouring and benzoate preservatives on the behaviour of 3 year old children which is detectable by parents but not by a simple clinic assessment. Subgroups are not made more vulnerable to this effect by their prior levels of hyperactivity or by atopy.

Effect of dietary protein content on behavior in dogs

OBJECTIVE

To determine the effect that feeding diets containing a low (17%), medium (25%), or high (32%) protein content would have on behavior in dogs.

DESIGN

Prospective, controlled study.

ANIMALS

12 dogs with dominance aggression, 12 dogs with hyperactivity, 12 dogs with territorial aggression, and 14 control dogs without behavioral problems.

PROCEDURE

Dogs were fed each of the diets for a 2-week period, and owners were instructed to score their dogs' behavior on a daily basis.

RESULTS

Behavior of the dogs with dominance aggression, dogs with hyperactivity, and control dogs was unchanged by the dietary manipulations. Territorial aggression was significantly reduced when dogs were fed the low- or medium-protein diet, compared with territorial aggression when fed the high-protein diet. Post hoc analysis indicated that this effect was attributable to a marked reduction in aggression in a subset of the group (n = 7) in which territorial aggression was a result of fear.

CLINICAL IMPLICATIONS

Results of this study suggest that a reduction in dietary protein content is not generally useful in the treatment of behavior problems in dogs, but may be appropriate in dogs with territorial aggression that is a result of fear.

Effect of diet treatment on enuresis in children with migraine or hyperkinetic behavior

Twenty-one children with migraine and/or hyperkinetic behavior disorder which was successfully treated with an oligoantigenic (few-foods) diet also suffered from nocturnal and/or diurnal enuresis. On diet, the enuresis stopped in 12 of these children and improved in an additional four. Identification of provoking foods was by sequential reintroduction of the foods that were avoided on the oligoantigenic diet. In eight of the 12 children who recovered on the oligoantigenic diet and in the four who improved, reintroduction of one or more foods provoked a reproducible relapse of the enuresis. Nine children were subjected to a placebo-controlled, double-blind reintroduction of provoking foods. Six children relapsed during testing with incriminated foods; none reacted to placebo. Enuresis in food-induced migraine and/or behavior disorder seems to respond, in some patients, to avoidance of provoking foods.

Synthetic food colourings and 'hyperactivity': a double-blind crossover study

Of 220 children referred for suspected 'hyperactivity', 55 were subjected to a 6 week trial of the Feingold diet. Forty (72.7%) demonstrated improved behaviour and 26 (47.3%) remained improved following liberalization of the diet over a period of 3-6 months. The parents of 14 children claimed that a particular cluster of behaviours was associated with the ingestion of foods containing synthetic colourings. A double-blind crossover study, employing a single-subject repeated measures design was conducted, using eight of these children. Subjects were maintained on a diet free from synthetic additives and were challenged daily for 18 weeks with either placebo (during lead-in and washout periods) or 50 mg of either tartrazine or carmoisine, each for 2 separate weeks. Two significant reactors were identified whose behavioural pattern featured extreme irritability, restlessness and sleep disturbance. One of the reactors did not have inattention as a feature. The findings raise the issue of whether the strict criteria for inclusion in studies concerned with 'hyperactivity' based on 'attention deficit disorder' may miss children who indicate behavioural changes associated with the ingestion of food colourings. Moreover, for further studies, the need to construct a behavioural rating instrument specifically validated for dye challenge is suggested.

Dietary characteristics of hyperactive and control boys

The purpose of this study was to examine the relationship between dietary habits and behavioral problems in hyperactive boys and to determine how successful parents are in maintaining their children on sugar-free diets. The mothers of 32 hyperactive boys aged 7 to 12 years and 26 matched controls completed 3-day diet records and food frequency interviews. The hyperactive boys were also evaluated in a playroom for impulsivity, compliance, attention, motor activity, memory, and learning. No differences were found in any of the measures of dietary content between the hyperactive and control groups. The only significant differences between those two groups were a lower socioeconomic status and a greater number of parents attempting sugar-restricted diets in the hyperactive group. Boys on sugar-restricted diets had only one significant dietary difference from those not restricted. Correlations between the information obtained in food frequency interviews and in 3-day diet histories were not significant (r = .06 to .33) for the hyperactive group, but the food frequency interviews were significant for the control group (r = .41 to .47). Four behavioral variables showed significant partial correlations with reported sugar intake. Overall, the results demonstrated that the diets of a group of hyperactive boys were similar to those of a control group. There appeared to be little difference between the diets of the families that attempted to restrict sugar and those that did not.

Nutrition and behavior: complex interdisciplinary research

Nutrition and behavior research presents a particularly challenging field of study for scientists. An overview is provided of research on nutrition and behavior of adequately nourished populations in industrialized countries. Discussions and findings from research presented include: refined carbohydrate consumption, maladaptive behavior, behavior disorders and learning; a history of the 'Feingold diet' and the basis for its controversy; an examination of recent critiques of research on artificial food dyes and hyperkinesis; indications for dietary intervention of hyperactive preschoolers; the role of iron in behavior disorders; effects of sub-clinical vitamin deficiencies on behavior; trace element analysis studies and violent behavior; and, suggested guidelines for further research into this complex and challenging field. Studies cited are from Canada, France, the United Kingdom, and the United States.

Food faddism in pediatrics

An understanding of the nutritional requirements of healthy, growing infants and children is required to guide parents in appropriate feeding practices which are consistent with their chosen life styles. Among the several prevalent types of food faddism are some that are not harmful or can beneficial, such as breast-feeding, others than can be of long-term benefit but that have limitations in infants and children, and others that can affect infants and children adversely. Those wishing to feed their children unconventional diets should have such diets carefully evaluated to avoid deficiencies of essential nutrients.

Diet and hyperkinesis--an update

Ten years ago, Dr. Feingold proposed that hyperactivity and learning disabilities in children are commonly caused by the ingestion of food additives and claimed that elimination of foods with additives from the diet resulted in major improvements in three-quarters of hyperactive children. In the last five years, controlled double-blind studies have been conducted by many investigators to test this hypothesis. The results, which are mainly negative, are summarized. The authors conclude that 2% (contrasted with Feingold's claims of 75%) of hyperactive children respond adversely to dye additives. Even the 2% are questionable. There is no need for high-priority research or for changes in public policy regarding the use and labeling of foods containing additives. Hyperkinesis has multiple etiologies, which require other types of biological and psychological research.

Nutrition, brain function and behavior

Current food intake has been shown to directly affect neurotransmission, with resultant modification of behavior. The role of vitamin co-factors in brain function is discussed, with emphasis on changes in mood and neurological function with deficiency. The use of megadoses of vitamins for the treatment of psychiatric diseases has little scientific support at this time. Current research also does not substantiate the Feingold thesis of improvement in childhood hyperkinesis when an additive-free diet is consumed. The effects of medications used to moderate mood are related to changes in nutrient intake that in turn alters weight status. In addition, the effect of certain nutrients modifying the dose response to mood altering drugs has been discussed. Finally evidence for mood state directly affecting the capacity of the body to utilize nutrients is presented.