There is a well-documented relationship between dietary factors, health and human behavior. Severe malnutrition produces neurological and psychiatric symptoms. It is also assumed that dietary factors play a role in common mental disorders, such as ADHD, but this is less established and more difficult to investigate. A few studies have documented a beneficial effect of dietary interventions and vitamin supplements in ADHD in children and adults.
To examine the nutritional status in ADHD, Landaas et al. recently compared blood vitamin levels in 133 adult ADHD patients and 131 healthy controls. In the ADHD group there was a clear overrepresentation in the group with low levels of vitamins B2, B6 and B9.
It is yet unclear whether these vitamin levels are associated with ADHD symptoms, or whether they are the result of altered dietary intake or metabolism in ADHD patients. However, it is possible that the differences reflect dietary habits that are different in a subgroup of ADHD patients and controls. Dietary habits are established early during life and may last into adulthood. It is possible that suboptimal dietary habits may precipitate, exacerbate or maintain symptoms of ADHD. More research in larger samples is obviously needed to clarify these issues.