Anxiety Biomarkers: When It Is Your Body, Not Your Mind: Anxiety often stems from metabolic, hormonal, or nutritional imbalances that respond to targeted treatment

Magnesium is a crucial cofactor for GABA and serotonin synthesis and is responsible for relaxing muscles and calming the nervous system. Deficiency is widespread (up to 75% of the population) and directly causes anxiety, tremors, and muscle tension. Magnesium deficiency is rarely diagnosed because most labs do not test serum magnesium, which is a poor marker.

Vitamin D is a neurohormone that regulates serotonin and dopamine synthesis and modulates immune cell function. Deficiency is associated with anxiety, depression, and seasonal affective disorder. Up to 42% of the population is deficient, especially in winter months or with limited sun exposure.

Thyroid dysfunction is a common cause of anxiety. Hyperthyroidism produces classic anxiety symptoms (racing heart, tremors, panic); hypothyroidism produces anxiety mixed with fatigue. TSH, free T4, and free T3 should all be optimal.

Cortisol is elevated in chronic stress or adrenal dysfunction. Chronically elevated cortisol both causes anxiety and prevents GABA and serotonin synthesis, creating a vicious cycle. Testing morning cortisol reveals whether your adrenal system is dysregulated.

Iron deficiency impairs dopamine synthesis and reduces cerebral oxygen delivery, both of which can manifest as anxiety. Restless leg syndrome, another common manifestation of iron deficiency, directly reduces sleep quality and amplifies anxiety.