Statistics from Altmetric.com
Editor,—In the management section of his paper on attention deficit hyperactivity disorder (ADHD) which focuses mainly on medication,1 Hill gives the erroneous impression that managing hyperactivity by diet is difficult and ineffective: those who use it regularly to control ADHD know that this is not the case.
Standard diets are not helpful in the management of this disorder because the foods which provoke hyperactive behaviour are different for each child. Few parents succeed in identifying the foods which affect their child without help, but an elimination diet is effective in most cases. Deficiencies of omega 6 essential fatty acids are common in these children2 so, in addition to the calcium supplement given to all children avoiding milk, evening primrose oil, borage oil, and cofactors such as zinc, are also usually recommended. Under this regimen, the hair-raising first consultation with the child is often followed by a quiet and cooperative second or third visit. If they have had help with finding alternative foods, most parents find it surprisingly easy to keep the child to the diet most of the time after the first few weeks because the child usually prefers to feel well.
There are three good trials3-5 which report substantial improvement and significant reduction of Connor’s scores in hyperactive children on a hypoallergenic diet; over 70% of children responded in each study. The results were confirmed with double blind placebo controlled challenges3-5; significantly higher scores were recorded during periods on challenge food rather than on placebo. These trials did indeed use a stringent few-food hypoallergenic diet during the investigative phase, with very slow challenges. However, in the clinic, if you start by taking a good history (preferably when the child is not present), it is often possible to see good results in hyperactive children fairly quickly and with relatively few exclusions.
The principles of elimination dieting are set out in a recent text.6 Provoking foods or food additives are usually those which are eaten frequently; it is rare for a single item to be responsible for ADHD. Most of the probable provoking substances must be avoided completely and at the same time to get good results. It may be sufficient to avoid additives (especially colours and preservatives in food, drink, medicine, and toothpaste), chocolate, milk, and orange, to which most hyperactive children react.4 However, reactions to cheese, wheat, and other fruit are also common and any food may provoke hyperactivity, especially if eaten frequently. An improvement is often seen in children within 3–7 days, and single open oral challenges are usually sufficient if given within three weeks. Foods which cause a distinct deterioration in behaviour should be avoided for several months, by which time they can often be tolerated if not eaten too frequently. The diet may relieve other conditions—for example, glue ear or abdominal pain, which are also present in many of these children2 6; in boys with eczema it is sensible to arrange challenges under supervision as there have been reports of anaphylaxis. Finally, the nutritional quality of longer term diets should be checked by a dietician.
If the diet is effective, behaviour often reverts to normal, to the great relief of all concerned. In view of the potential toxicity of medication in children and its limited effectiveness, all families with hyperactive children should be offered help in detecting offending foods. It is more appropriate to reserve medication for those who fail.
Professor Till comments:
Of course an elimination diet works for some children with attention deficit hyperactivity disorder; I use it myself. I agree that there is good evidence for the effectiveness of the few-food diet, but its effect size is small compared with that of medication. Parents committed to dietary treatment have usually tried it. Those who are uncommitted may find it cumbersome. I know of no convincing hard evidence that confirms an allergenic mechanism. The approach recommended by your participants is a mixture of elimination diets, additive restriction, and magic ingredients, which I do not think has been tested scientifically. Nevertheless, I expect that borage oil is very nice.
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.