Zinc in Attention-Deficit/Hyperactivity Disorder

Abstract

Objective:The aim of this study was to review the published evidence for a role of zinc nutrition in attentiondeficit/hyperactivity disorder (ADHD). Method:A computer literature search was supplemented by the authors' knowledge. Results:Numerous controlled studies report cross-sectional evidence of lower zinc tissue levels (serum, red cells, hair, urine, nails) in children who have ADHD, compared to normal controls and population norms. A few studies show correlations of zinc level with either clinical severity or a change thereof in response to stimulant or chemical challenge. Two placebo-controlled trials-one of zinc monotherapy, the other of zinc supplementation of methylphenidate-reported significant benefit. However, diagnostic procedures and sample representativeness were often not clear, and most such reports have come from countries and cultures with different diets and/or socioeconomic realities than are found in the United States (only one American sample in nine published reports). In particular, both positive clinical trials of zinc supplementation came from the Mid-East (Turkey and Iran), an area with suspected endemic zinc deficiency. The largest of these trials used zinc doses above the recommended upper tolerable limit and had a 2 in 3 dropout rate. Conclusion:It is not clear how well the accumulating evidence for a possible role of zinc in ADHD applies to middle-class American children. However, the evidence appears strong enough to warrant further controlled study in well-diagnosed samples representative of the socioeconomic spectrum. Hypothesistesting clinical trials are needed of this potential treatment that, if found effective, might become a relatively safe, cheap substitute for, or adjunct to, current treatments in some patients. At present, it should remain an investigational treatment.

Oxidative and nitrosative stress in ADHD: possible causes and the potential of antioxidant-targeted therapies

“…Zinc has numerous biological roles in the body and has strong antioxidant activity (Prasad 2014). Zinc deficiency and reduced zinc concentrations are often found in people with ADHD (Arnold and DiSilvestro 2005), and this has been confirmed in a meta-analysis by Scassellati and colleagues (2012). More recently, lowered vitamin D levels and vitamin D deficiency have also been reported in people with ADHD (Bener and Kamal 2014;Goksugur et al 2014).…”

Significance of long-chain polyunsaturated fatty acids (PUFAs) for the development and behaviour of children

“…Apart from genetic factors, the status of mineral cofactors also appears to have an influence on the conversion and status of ω-3 fatty acids. Minerals such as magnesium [43] and zinc [8] are crucial desaturase enzyme cofactors. A lack of these micronutrients results in an inhibition of enzyme activity.…”

Oral Zinc Sulphate Supplementation for Six Months in SCA2 Patients: A Randomized, Double-Blind, Placebo-Controlled Trial

“…In 1996, Golub et al [32] reported attentional impairment at levels that did not cause growth retardation in moderately zincdeprived monkeys. Also many children with AttentionDeficit/Hyperactivity Disorder have reduced zinc levels compared to normal controls [33]. The non-significant changes in maximal saccadic velocity and saccadic deviation values in zinc group are in accordance with the nature and extension of these saccadic abnormalities in SCA2 patients.…”