Artificial food colors (AFCs) have been linked with worsening of the symptoms of attention-deficit hyperactivity disorder (ADHD). Although not many studies have been conducted in this regard, a few diet studies have shown that children with ADHD are sensitive to AFCs as well as foods such as milk, chocolate, soy, eggs, wheat, corn, legumes, grapes, tomatoes, and oranges. This review analyzes two recent and large studies on ADHD that showed sensitivity to food colors and a few other compounds. The results show that it would be appropriate to conduct an experimental dietary investigation on children who are not responding to conventional treatment.
ADHD affects nearly 8% of school-aged children in the US and is the most common childhood psychiatric disorder. These children are hyperactive and impulsive. They may also have certain other disorders affecting their conduct, mood, and learning abilities. These children are treated using behavior therapy. Studies show that 70% improve significantly on medication, while the others have side effects such as loss of appetite, decreased growth, sleeplessness, and headache. The origin of ADHD still remains unclear but the reason could be biological or based on multiple factors. Although surrounded by controversy, another cause that was investigated was the lack of tolerance to certain food additives. In the early 1970s, Dr. Benjamin Feingold initiated a diet called the “Kaiser Permanente diet” or “K-P diet” free of all AFCs, flavors, and salicylate, which was thought to worsen the symptoms of ADHD. Although well received by many, it was a controversial and well-debated subject. This review discusses the studies performed over the past 35 years on three major diet modifications for ADHD.
- All articles pertaining to the three major diet modifications over the past 35 years were analyzed and evaluated.
- The studies on Feingold’s K-P diet were evaluated. The science behind the restriction of certain foods was also evaluated.
- Most of these studies compared a group of children with ADHD taking diets such as K-P diets with a placebo group.
- Studies on the specific effects of artificial food color as well as those on the elimination of foods were also analyzed.
- In a study where children with ADHD were given the K-P diet for four weeks, both parents and their teachers rated them as being less hyperactive.
- At least 11-33% of children with ADHD responded to the K-P diet in all the studies that were compared.
- In two other studies where the children were on artificial color eliminated diets, the parents and teachers reported a reduction in their behavior problems at 57% and 34%, respectively.
- Artificial food color induced hyperactivity, restlessness, and severe sleep disturbances.
- On prescription of a chemically defined diet providing all nutritional needs for the children with ADHD, the parents and teachers reported significant improvement.
Most of the studies in each category of dietary modification were contradicting each other. The K-P diet was found to have lower levels of calcium, vitamin B, and vitamin C. Many of the studies involving the dietary changes had no significant effect in comparison to the placebo group. Even if the diets were supportive, it is still unclear whether the diets could be sustained over a long term in children.
This review highlights the major diet modifications required for children with ADHD. The diagnosis of allergic conditions to food additives in comparison to food alone is a complex issue. Some children may also react adversely to non-causative agents of the symptoms of ADHD. The parents of these children must be well informed and educated by doctors and dieticians over this major health concern. It was also noted in this review that modified diets work best in younger children, and those with allergies and sleep problems. Parents must be advised that it might be a health risk to delay a conventional medical treatment to try the other available alternatives. Physicians and dieticians must be consulted before assessing the foods the children are allergic to before starting an elimination diet. This review also suggests that a literature search for various additives and allergic foods can be time consuming and unsuccessful due to the vastness of information.
For More Information:
Dietary Sensitivities and ADHD Symptoms: Thirty-Five Years of Research
Publication Journal: Clinical Pediatrics, 2011
By Laura J Stevens; Thomas Kuczek, PhD
From the Purdue University, West Lafayette, Indiana
*FYI Living Lab Reports Are Summaries of the Original Research.