Although attention-deficit/hyperactivity disorder (ADHD) has been related to nutrient deficiencies and “unhealthy” diets, to date there are no studies that examined the relationship between the Mediterranean diet and ADHD. We hypothesized that a low adherence to a Mediterranean diet would be positively associated with an increase in ADHD diagnosis.
A total of 120 children and adolescents (60 with newly diagnosed ADHD and 60 controls) were studied in a sex- and age-matched case-control study. ADHD diagnosis was made according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision. Energy, dietary intake, adherence to a Mediterranean diet, and familial background were measured. Logistic regression was used to determine associations between the adherence to a Mediterranean diet and ADHD.
Lower adherence to a Mediterranean diet was associated with ADHD diagnosis (odds ratio: 7.07; 95% confidence interval: 2.65–18.84; relative risk: 2.80; 95% confidence interval: 1.54–5.25). Both remained significant after adjusting for potential confounders. Lower frequency of consuming fruit, vegetables, pasta, and rice and higher frequency of skipping breakfast and eating at fast-food restaurants were associated with ADHD diagnosis (P < .05). High consumption of sugar, candy, cola beverages, and noncola soft drinks (P < .01) and low consumption of fatty fish (P < .05) were also associated with a higher prevalence of ADHD diagnosis.
Although these cross-sectional associations do not establish causality, they raise the question of whether low adherence to a Mediterranean diet might play a role in ADHD development. Our data support the notion that not only “specific nutrients” but also the “whole diet” should be considered in ADHD.
Comments
RE: Mediterranean Diet and ADHD- Dr. Burke's comments
Dear Dr Burke,
We appreciate your comment. We are aware of the complexity of ADHD and the different environmental factors, which can contribute to the development of ADHD. We carefully pointed out in our paper that our design case-control study prevents our ability to assess cause-and-effect associations. In addition, we also discussed that the relationship found between diet and ADHD could represent reverse causation and also how the family may play a role, since a healthy diet is related of a better functioning family. For all these factors, we consider that is a vicious cycle: impulsiveness and family dysfunction could lead to a worse choice of foods, lowering diet quality, which eventually could lead to a low intake of certain nutrients which may induce certain nutritional subclinical deficiencies and, hence, worsen ADHD symptoms.
RE: Mediterranean Diet and ADHD
Have the authors considered that the lack of adherence to a Mediterranean Diet may not actually be predisposing factor to the development of ADHD, but rather a reflection of a more chaotic family lifestyle? So that the relative dietary deficiencies are not the factor that predisposes to the development of ADHD? Rather, the same chaotic lifestyle in which the child lives - too much TV and other screen time, not enough time with puzzles and other stimulating games which would help the child development a better attention span - is reflected in the family's food preparation, so that the family relies more on fast food and processed food rather than healthier choices? And so rather than being causal the child's diet simply reflects other environmental factors which predispose to the development of ADHD?