Hyperthyroidism mimics panic disorder. B12 deficiency impairs neurotransmitter production. Low iron causes palpitations and breathlessness. Blood sugar instability triggers episodic anxiety, shakiness, and irritability. These are not psychological problems. They are biochemical ones — testable, measurable, and correctable. A blood test cannot diagnose an anxiety disorder. But it can identify physical causes that are being treated as psychiatric ones. The TrueVitals Ultimate panel covers every marker that should be checked before accepting an anxiety diagnosis, across 114 biomarkers for £349.
Each of these produces symptoms that overlap with generalised anxiety disorder or panic attacks. Each is detectable by blood test. Each is treatable without psychiatric medication if identified as the cause.
Hyperthyroidism accelerates metabolism, causing rapid heartbeat, tremor, sweating, irritability, insomnia, and a persistent sense of nervousness that is virtually indistinguishable from panic disorder. Hypothyroidism can also cause anxiety alongside depression, fatigue, and brain fog. A full thyroid panel (TSH, Free T4, Free T3, Anti-TPO antibodies) is essential. TSH alone can miss subclinical hyperthyroidism and autoimmune thyroiditis, both of which produce anxiety symptoms before TSH shifts. Thyroid blood test guide.
B12 is essential for the production of serotonin and dopamine. Deficiency impairs the methylation cycle that produces these neurotransmitters, leading to anxiety, depression, irritability, and cognitive dysfunction. B12 deficiency is common in people over 50 (reduced absorption), vegans and vegetarians (dietary insufficiency), and anyone taking metformin or proton pump inhibitors (medication-induced depletion). Folate deficiency compounds the effect through the same methylation pathway. Vitamin deficiency guide.
Iron deficiency causes palpitations, breathlessness, dizziness, and a racing heart. These symptoms are frequently mistaken for panic attacks. Ferritin below 30 ng/mL can produce these symptoms even when haemoglobin is normal — iron deficiency without anaemia. Women with heavy periods are particularly susceptible. The NHS flags ferritin only below 15 ng/mL. A woman with ferritin of 18, palpitations, and breathlessness may be told her bloods are "normal" and prescribed an SSRI when iron supplementation would resolve the symptoms. Iron blood test guide.
Vitamin D receptors are found throughout the brain, including in regions that regulate the fear response and stress reactivity. Multiple studies have found that people with anxiety disorders have lower average vitamin D levels than age-matched controls. Vitamin D deficiency affects approximately 57% of UK adults in winter. Supplementation studies have shown reductions in anxiety scores after 12 weeks of correction. It is the most common deficiency in the UK and one of the easiest to fix.
When blood sugar drops rapidly after a carbohydrate-heavy meal (reactive hypoglycaemia), the body releases adrenaline and cortisol to compensate. This produces shakiness, sweating, rapid heartbeat, irritability, and a sense of dread — indistinguishable from a panic attack. Fasting insulin, HOMA-IR, HbA1c, and fasting glucose together reveal whether blood sugar regulation is impaired. Standard GP testing checks fasting glucose and sometimes HbA1c but misses fasting insulin and HOMA-IR entirely. Insulin resistance guide.
Chronic stress elevates cortisol, which disrupts sleep, amplifies the stress response, impairs thyroid conversion, and compounds anxiety. Cortisol follows a circadian rhythm (highest in the morning, declining through the day). A morning cortisol level reveals whether the baseline is elevated. While a single cortisol measurement has limitations, it provides context alongside thyroid, metabolic, and hormonal markers. An elevated cortisol with suppressed thyroid and elevated fasting insulin paints a very different picture from anxiety alone. Stress blood test guide.
NICE guidelines recommend excluding physical causes of anxiety symptoms before starting treatment. In practice, the pressure of 10-minute appointments and limited testing budgets means many patients are prescribed SSRIs without a single blood test. When tests are ordered, they typically include TSH (alone, without Free T3, Free T4, or antibodies), haemoglobin (without ferritin), and fasting glucose (without fasting insulin). This misses subclinical thyroid disease, iron deficiency without anaemia, insulin resistance, B12 deficiency, and vitamin D deficiency — all common, all treatable, all capable of producing anxiety symptoms.
This is not a criticism of GPs. It is a structural problem. The markers exist. The evidence for testing them is strong. The pathway doesn't make them easy to request. A comprehensive private panel bypasses the pathway and tests all of them simultaneously. If a physical cause is found, you take the data to your GP and the conversation becomes specific and actionable. If the physical markers are all normal, you have genuine reassurance that your anxiety is not being driven by an untested deficiency or imbalance.
The TrueVitals Ultimate panel includes full thyroid with antibodies, B12, folate, vitamin D, ferritin, full iron studies, fasting insulin, HOMA-IR, HbA1c, cortisol, testosterone, SHBG, hs-CRP, homocysteine, and magnesium — alongside 100+ additional markers. 114 biomarkers. Results in 48 hours. £349.
If a physical cause is found: elevated TSH or suppressed TSH (thyroid), low B12 or folate, low ferritin, low vitamin D, elevated fasting insulin, or elevated cortisol alongside anxiety symptoms — take the results to your GP. The conversation shifts from "I feel anxious" (which gets an SSRI prescription) to "my thyroid antibodies are elevated and my Free T3 is low" (which gets a specific investigation and targeted treatment). Data changes the dynamic.
If everything is normal: that is genuinely valuable information. It means your anxiety is unlikely to be driven by a correctable deficiency or hormonal imbalance. Psychological approaches (CBT, therapy, lifestyle changes) can proceed with confidence that nothing biochemical is being missed. Normal results are not a wasted test. They are a cleared runway.
If multiple markers are borderline: this is the most common pattern. Ferritin at 22 (low but "normal"), vitamin D at 38 nmol/L (insufficient but above the NHS deficiency threshold), TSH at 3.8 (within range but above the optimal threshold). No single marker is flagged. The cumulative effect of multiple suboptimal systems may be driving symptoms. A comprehensive panel with cross-system analysis identifies this pattern. A series of individual GP tests, ordered months apart, does not.
The TrueVitals report analyses thyroid, metabolic, hormonal, nutritional, and inflammatory markers using AI cross-system analysis. If your Free T3 is low, your vitamin D is insufficient, and your ferritin is suboptimal, the report identifies the combined pattern and provides specific recommendations for each. It doesn't diagnose anxiety. It identifies whether your body's biochemistry is contributing to your symptoms — and tells you exactly what to do about it. A medical professional reviews every report.
114 biomarkers including full thyroid, B12, vitamin D, ferritin, fasting insulin, cortisol, and every marker that should be checked before accepting an anxiety diagnosis. Results in 48 hours.
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