ADHD Ultimate Panel

Zinc is an essential trace element required for over 300 metalloenzymes involved in neurotransmitter synthesis, synaptic plasticity, and neuronal signalling. It modulates dopamine and glutamate receptor function and is concentrated in hippocampal and cortical regions critical to attention and executive function. Serum zinc represents only a small fraction of total-body stores and fluctuates with inflammation, albumin status, and recent intake.

Low zinc has been associated with attention deficits, hyperactivity, and impulsivity in some observational studies, though the relationship is complex and not consistently reproduced. Zinc supplementation trials in ADHD show mixed outcomes. Serum zinc is an indirect marker of status and should be interpreted alongside clinical context and dietary history.

Magnesium is the second most abundant intracellular cation and serves as a cofactor for enzymes regulating energy production, protein synthesis, and neurotransmitter release. It modulates NMDA receptor activity, influences GABAergic and dopaminergic pathways, and stabilises neuronal membranes. Serum magnesium reflects less than 1% of total-body stores, so deficiency can exist despite normal serum concentrations.

Magnesium deficiency has been linked to irritability, attention difficulties, and hyperactivity in children, and supplementation is commonly recommended in integrative ADHD protocols. However, serum magnesium is an insensitive marker of tissue status, and the evidence base for benefit in ADHD remains limited.

Copper is an essential cofactor for enzymes involved in neurotransmitter synthesis (dopamine beta-hydroxylase, tyrosinase), mitochondrial respiration, and antioxidant defence. Most circulating copper is bound to ceruloplasmin. Imbalances affect catecholamine production, iron metabolism, and oxidative stress pathways relevant to neuropsychiatric function.

Both deficiency and excess copper have been proposed to influence attention, mood, and behaviour. Some functional practitioners interpret elevated copper or a high copper:zinc ratio as a contributor to hyperactivity and anxiety, though robust clinical evidence for these associations in ADHD is lacking.

Ferritin is the primary intracellular iron-storage protein; serum ferritin generally correlates with total-body iron stores, though it is also an acute-phase reactant and can be elevated in inflammation, infection, or liver disease independently of iron status. Iron is required for dopamine synthesis, myelination, and mitochondrial function in the central nervous system.

Low ferritin (<30 ng/mL, or <50 ng/mL in some functional protocols) has been associated with restless legs, sleep disturbance, and inattention in children and adults, and iron supplementation in iron-deficient individuals may improve ADHD symptoms. Ferritin is the most accessible marker of iron status, but interpretation requires clinical context.

25-Hydroxyvitamin D is the major circulating form of vitamin D and the best marker of vitamin D status. It is hydroxylated in the kidney to the active hormone calcitriol, which acts through the vitamin D receptor expressed widely in the brain, influencing dopamine synthesis, neuroprotection, and immune modulation.

Vitamin D deficiency is common and has been associated with mood disorders, cognitive impairment, and, in some studies, ADHD symptoms. Supplementation trials show inconsistent effects on attention or behaviour, suggesting that correction of deficiency is important for general neurodevelopment but not a specific ADHD treatment.

The Omega-3 Index quantifies eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) as a percentage of total red blood cell membrane fatty acids, reflecting long-term dietary intake and tissue incorporation. EPA and DHA are structural components of neuronal membranes and precursors to anti-inflammatory mediators; DHA is especially concentrated in the brain and retina.

Meta-analyses of omega-3 supplementation in ADHD show modest benefits, particularly for inattention, though effect sizes are small and inconsistent. The Omega-3 Index provides an objective measure of status that may help guide supplementation, but it is not diagnostic and does not predict treatment response in an individual.

Homocysteine is an intermediate in methionine metabolism, dependent on folate, vitamins B6 and B12, and betaine for remethylation or transsulphuration. Elevated homocysteine reflects impaired one-carbon metabolism and is a marker of oxidative stress, endothelial dysfunction, and, in extreme cases, neurotoxicity.

Mild hyperhomocysteinaemia has been proposed as a marker of methylation insufficiency and oxidative stress in neurodevelopmental and psychiatric disorders, though direct evidence linking it to ADHD pathophysiology is limited. Elevated homocysteine may identify B-vitamin deficiencies amenable to supplementation.

C-reactive protein is an acute-phase reactant synthesised by the liver in response to IL-6 and other inflammatory cytokines. High-sensitivity assays detect low-grade chronic inflammation associated with metabolic and cardiovascular disease. Neuroinflammation and peripheral inflammatory markers have been investigated as potential contributors to psychiatric and neurodevelopmental disorders.

Elevated hs-CRP has been observed in some cohorts of children and adults with ADHD, though findings are inconsistent and causality is not established. It is included in comprehensive functional panels as a general marker of systemic inflammation, not as a diagnostic or specific marker of ADHD.

TSH is secreted by the anterior pituitary in response to hypothalamic TRH and regulates thyroid hormone synthesis and release. It is the most sensitive first-line marker of thyroid dysfunction, rising in primary hypothyroidism and falling in hyperthyroidism. Thyroid hormones are critical for neurodevelopment, myelination, and regulation of metabolism and arousal.

Both overt and subclinical thyroid dysfunction can present with inattention, cognitive slowing, or behavioural changes that overlap with or exacerbate ADHD symptoms. TSH screening is standard in the evaluation of attention and behavioural concerns to exclude a thyroid contribution.

HbA1c reflects glycation of haemoglobin over the preceding 2–3 months and is used to diagnose and monitor diabetes. Chronic hyperglycaemia and insulin resistance affect brain glucose metabolism, neurotransmitter synthesis, and vascular health, with implications for cognition and mood.

Insulin resistance and dysglycaemia are not direct causes of ADHD but are more prevalent in individuals with ADHD and may exacerbate symptoms through effects on energy regulation, inflammation, and sleep. HbA1c is included as a metabolic screen.

The copper:zinc ratio is a calculated index reflecting the balance between these two trace elements, which interact in enzymatic pathways, immune function, and oxidative stress regulation. Interpretation is complicated by the fact that both are influenced by inflammation, dietary intake, and binding proteins.

An elevated copper:zinc ratio has been proposed as a marker of oxidative stress, oestrogen dominance, or pyrrole disorder in functional medicine, and some practitioners link it to hyperactivity and anxiety. However, the ratio is not validated as a diagnostic or therapeutic target in ADHD, and reference ranges are inconsistent.