Biomarkers for tracking metabolic changes pre-post nutritional epigenetics diet/intervention to prevent autism and attention deficit/hyperactivity disorders in children

Abstract

The prevalence of autism and attention deficit/hyperactivity disorders is increasing worldwide. Recent studies suggest the excessive intake of ultra-processed food plays a role in the inheritance of these disorders via heavy metal exposures and nutritional deficits that impact the expression of genes. In the case of the metallothionein (MT) gene, biomarker studies show dietary zinc (Zn) deficits impact MT protein levels in children with autism and are associated with the bioaccumulation of lead and/or mercury in children exhibiting autism/attention deficit/hyperactivity disorders symptomology. The impact of dietary changes on lead and mercury exposures and MT gene behavior could be determined using a randomized test and control group design. Pregnant women serving in the test-group would participate in a nutritional epigenetics education intervention/course designed to reduce ultra-processed food intake and heavy metal levels in blood while increasing whole food intake and MT and Zn levels. Changes in maternal diet would be measured using data derived from an online diet survey administered to the test and control groups pre-post intervention. Changes in maternal lead, mercury, Zn, and MT levels would be measured via blood sample analyses prior to the intervention and after childbirth via cord blood analyses to determine infant risk factors.

Keywords: Attention deficit/hyperactivity disorder; Autism; Lead; Mercury; Metallothionein; Nutritional epigenetics; Zinc.

Figure 1

Metallothionein protein molecule. Figure shows three zinc atoms, and one copper atom bound to yellow cysteine residues which connect to blue histidine molecules. Selenium, represented by red, plays a key role in reducing oxidative stress from the heavy metals that bind with and are transported through the excretion process by metallothionein proteins. MT: Metallothionein; Zn: Zinc; Cu: Copper; Se: Selenium.

Figure 2

Nutritional epigenetics model for autism and attention deficit/hyperactivity disorders. Figure shows a simplified version of the nutritional epigenetics model. Poor prenatal diet of excessive ultra-processed food intake results in the consumption of food colors, vegetable oils, refined sugars and preservatives. These food ingredients contribute to mercury (Hg) and lead (Pb) exposures and deficits in nutrition such as selenium and zinc losses. Zinc loss and selenium deficits disrupt metallothionein protein production which leads to the bioaccumulation of Hg and Pb in the blood. These heavy metals create oxidative stress and symptoms associated with child behavioral and learning disorders. Oxidative stress impacts DNA methylation patterns creating adverse child health and learning outcomes in the next generation. A healthy diet, free of ultra-processed foods, may reduce Hg and Pb levels and symptoms associated with behavioral and learning disorders (e.g., autism, attention deficit/hyperactivity disorders). MT: Metallothionein; ADHD: Attention deficit/hyperactivity disorders; HFCS: High fructose corn syrup; Zn: Zinc; Se: Selenium; Hg: Mercury; Pb: Lead.