DR. BRAGANZA is an assistant professor of pediatrics at Children's Hospital at Montefiore Albert Einstein College of Medicine,
Bronx, NY.
DR. GALVEZ is an assistant professor of pediatrics and of community and preventive medicine at Mount Sinai School of Medicine,
New York, NY.
DR. OZUAH is a professor of pediatrics and interim university chairman at Children's Hospital at Montefiore Albert Einstein
College of Medicine, Bronx, NY.
The authors have nothing to disclose in regard to affiliations with, or financial interests in, any organization that may
have an interest in any part of this article.
Nutritional interventions
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Attention-deficit hyperactivity disorder (ADHD) is characterized by symptoms of inattention, hyperactivity, and impulsivity
that impair a child's ability to function.1,2 Although the treatment mainstays for ADHD in children are stimulant medications and behavior therapy,3 the medical literature indicates that parents and caregivers of children who have the condition often use dietary interventions
in an attempt to manage the child's behavior.4-6 Despite controversy over the use of nutritional interventions for this disorder, both elimination diets and dietary supplementation
are common complementary and alternative medicine treatments for the inattentiveness, hyperactivity, and impulsivity of ADHD.4-6The effect of nutrition on mood and behavior is well known; certain protein-rich foods such as meat, cheese, and eggs contain
amino acids that are precursors of neurotransmitters such as serotonin, dopamine, and norepinephrine. These precursors cross
the blood-brain barrier and, through complex interactions, are synthesized into neurotransmitters. These neurotransmitters
are hypothesized to directly affect behavior and cognition.2
Enter the Feingold diet
The late pediatric allergist Benjamin Feingold, MD, was the leading proponent of a nutritional basis for hyperactivity in
children.2 Working with children who exhibited sensitivity to aspirin, foods, and food additives, Feingold described physical reactions
and behavioral changes—such as inattention—that he considered to be precursors of hyperactivity and learning disability. Feingold
suggested a causal relationship between the increased use of artificial colorings and flavorings in food products and the
incidence of hyperactivity and learning disability.7,8 Based on his observations, Feingold developed a salicylate elimination diet that prohibited not only the salicylate-containing
compounds aspirin and aspartame, and foods containing dyes and preservatives, but also apples, berries, grapes, oranges, peaches,
plums, cucumbers, and tomatoes. These fruits and vegetables were thought to form chemicals similar to acetylsalicylic acid,
which contained a so-called salicylate radical. Dr. Feingold did not, however, specify which of the salicylate chemicals could
produce an effect, and at what dosage.8 Feingold claimed that the schoolwork of an ADHD child who was on this diet would improve, and that hyperactive behaviors
would diminish.7,8
Does the diet have an effect?
Despite anecdotal reports and uncontrolled studies conducted in the 1970s that continued to suggest a relationship between
elimination diets and behavior, controversy developed within the scientific community over Feingold's claims.2,8 The most significant concern was a lack of prospective, randomized, controlled trials of the effect of salicylate compounds
on behavior: Which, if any, specific chemicals are responsible for the effect, and in what concentrations? A second concern
was that parents would alter their child's diet—thereby potentially influencing growth and development—based on anecdotal
observations alone. These concerns led to the establishment of the National Advisory Committee on Hyperkinesis and Food Additives,
which recommended that the Nutrition Foundation study the effects of the diet with food challenge.2
Early food challenge studies demonstrated no change in behavior when a child was on the Feingold diet.9 A later review of 13 double-blind, placebo-controlled trials in well-defined study population of 240 children demonstrated
that only 1% of children exhibited a consistent improvement of symptoms while on the diet.8 No change in behavior was reported in more than 90% of children challenged with standardized food dyes.8 These data provided limited support for any beneficial effect of the Feingold diet except in a small percentage of children
with a behavior disorder.
Feingold, today
Key Points
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The Feingold Association, on its Web site (www.feingold.org), describes a program that eliminates several classes of artificial colors, antioxidants, aspirin-containing products, and other products such
as fragrances to determine if certain foods trigger particular symptoms. (The association claims that eliminating other products,
such as fragrances, from the child's environment distinguishes its program from the Feingold diet alone.) The association asserts that in addition to hyperactivity, conditions such as asthma, ear infections, seizures, sleep
disorders, stomachaches, and bedwetting can also be mitigated by the program. It further claims that the program can improve
a child's reasoning and attention span, and curb self-mutilating behavior. There is a lack of sufficient evidence thus far
to support these claims. Any improvement that does occur is hypothesized to result from the fact that parents are paying more
attention to the child undergoing the program.
What about other dietary interventions for ADHD?
The concept of whether and how diet affects behavior is complex. Researchers continue to investigate the role of diet in learning
and in behavior disorders. In addition to food additives, many allergenic foods have been studied for their possible role
in inattention, hyperactivity, mood changes, attitude, and sleep.10,11
Recent rigorously designed studies have examined different food allergens and multiple forms of other offending agents. Generally
in these studies, a child is given a diet that eliminates common food allergens, whether milk, peanuts, soy, wheat, artificial
additives, or other foods or agents suspected of causing symptoms in that child. When—if—behavioral symptoms diminish, (usually,
the elimination period is maintained for two to four weeks), food items are reintroduced individually for several days. If
behavioral symptoms return after the child is given one of those foods or other agents, the child is challenged with that
food or agent, but disguised in smell, flavor, and texture to confirm its effect on him (her). More recently, researchers
have used double-blind, placebo-controlled studies to determine whether specific agents affect learning and behavior. In a
study of the effect, if any, of artificial food color and benzoate preservatives in 3-year-old children in a double-blind
crossover study, parents and a tester blinded to the diet observed and recorded the child's behavior.12 Although parents noted a significant increase in hyperactive behavior when the child was exposed to artificial food color
and benzoate preservative, objective testing through clinic assessments found no such difference. This makes it difficult
to draw valid conclusions about such dietary changes in pre-school age children, and more studies are needed to further evaluate
the role of artificial food color and preservatives in children.
Attention to the bottom line
A review of the literature leads us to conclude that scientific evidence is limited to support the use of the Feingold program
for treating ADHD symptoms. Although it is possible that a very small group of children who are allergic to salicylate compounds,
artificial colorings, or preservatives may show improvement in symptoms on this diet, evidence is insufficient to recommend
routine, widespread use of the Feingold diet to treat a child's ADHD symptoms.
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