Anxiety and Blood Tests: Physical Causes of Mental Symptoms

Before attributing anxiety to stress or mental health alone, consider that physical imbalances often cause or worsen anxiety symptoms.

Physical Causes of Anxiety

• Hyperthyroidism: Racing heart, tremors, anxiety
• Blood sugar swings: Reactive hypoglycemia
• Caffeine sensitivity: Exacerbates anxiety
• Magnesium deficiency: Promotes anxiety
• B vitamin deficiency: Affects nervous system
• Iron deficiency: Causes restlessness
• Hormonal changes: PMS, perimenopause

The Anxiety Lab Panel

Thyroid

Hyperthyroidism is a classic cause of anxiety. Test:

• TSH, Free T3, Free T4
• Thyroid antibodies (Graves' disease causes anxiety)

Blood Sugar

• Fasting glucose
• Fasting insulin
• HbA1c

Nutrients

• Magnesium (RBC magnesium preferred)
• Vitamin B12
• Vitamin D
• Ferritin

Hormones

• Cortisol (morning)
• Estrogen and progesterone (if symptoms are cyclical)

Inflammation

• hs-CRP

When Anxiety Is Cyclical

If anxiety worsens at certain times of your cycle, hormones may be involved. Track symptoms alongside your cycle and consider hormone testing.

Important Note

Physical causes don't exclude psychological ones - they often coexist. Addressing physical imbalances can make other treatments more effective.

References

• Bauer, M., et al. (2008). Thyroid hormones, serotonin and mood: of synergy and significance in the adult brain. Psychoneuroendocrinology, 33(10), 1285-1298.
• Boyle, N. B., et al. (2017). The effects of magnesium supplementation on subjective anxiety and stress: a systematic review. Nutrients, 9(5), 429.