OBJECTIVES:
The purpose of this study was to concisely review the available literature of nutritional and environmental factors on autistic spectrum and attention deficit hyperactivity disorder (ADHD).

DESIGN AND METHODS:
Review of journal articles found on the PubMed database and from information from several conference proceedings.

RESULTS:
Many, but not all, studies link exposure to toxins such as mercury, lead, pesticides, and in utero smoking exposure to higher levels of autism and/or ADHD. Some studies have reported many nutritional deficiencies in autism/ADHD patients. Numerous studies have reported that supplemental nutrients such as omega-3 fatty acids, vitamins, zinc, magnesium, and phytochemicals may provide moderate benefits to autism/ADHD patients. Avoidance of food allergens, food chemicals, and chelation therapy may also provide some relief to autism/ADHD patients.

CONCLUSIONS:
Autistic spectrum disorders and ADHD are complicated conditions in which nutritional and environmental factors play major roles. Larger studies are needed to determine optimum multifactorial treatment plans involving nutrition, environmental control,medication, and behavioral/education/speech/physical therapies.