Objective:This article is a review of research regarding attention deficit hyperactivity disorder and nutrition factors including essential fatty acids, micronutrients, refined sugars and food additives. Method: A literature search was conducted using PubMed, Scopous, Sciencedirect, Google Scholar Results: Nutritional factors such as food additives, refined sugars, fatty acids and micronutrients have all been correlated to ADHD. Recent trials with food additives suggest their removal from the diet may benefit susceptible children with hyperactivity disorders. Conclusions: More suitable research such as longitudinal studies and the use of placebos within randomized controlled trials are needed. In general, diet modification plays a major role in the management of ADHD and should be considered as part of the treatment.

Objective: Down syndrome (DS) is a common chromosomal disorder that cause to mental retardation in children. Alzheimer’s disease (AD) is also common in DS. Therefore, it is assumed that there is a same genetic basis. The aim of this study was to study and consider the overlap of DS and AD.Method: In this review article, published articles in science direct, Pubmed, Willy and Google were investigated between 1990 and 2015.Conclusion: Down syndrome is caused by trisomy 21. All genetic mutations in relation with AD are arising from accumulation of β amiloid. One of the genes involved in AD is APP that sited on chromosome 21. Moreover, the SOD1 also is sited on chromosome 21. Also, other hypothesis in relation with AD and DS has been considered. Significant percent of individual with DS are with AD, but its cause is not clear.