Not All Depression Is “Just” Depression
You have been feeling low, unmotivated, and joyless for weeks or months. Perhaps you have been told it is depression, maybe even offered an antidepressant prescription. But what if the cause of your low mood is not primarily psychological? What if your body is sending signals that something physical is wrong?
At our practice in Zürich Seefeld, I take a different approach to depression. Before attributing low mood solely to psychological causes, I systematically investigate the physical and metabolic factors that can drive or worsen depressive symptoms. In my experience, a significant number of patients diagnosed with depression have underlying medical conditions that, once treated, dramatically improve their mood.
Physical Conditions That Can Cause Depression
Hypothyroidism: An underactive thyroid is one of the most common and underdiagnosed physical causes of depression. Even subclinical hypothyroidism – where TSH is in the “high-normal” range – can cause significant mood disturbance. I always run a complete thyroid panel, not just TSH.
Vitamin D deficiency: Vitamin D receptors are abundant in brain regions involved in mood regulation. Deficiency is endemic in Switzerland, particularly during the winter months, and strongly correlates with depressive symptoms.
Vitamin B12 and folate deficiency: These vitamins are essential for methylation, a biochemical process critical for neurotransmitter production. Deficiency can directly impair serotonin, dopamine, and noradrenaline synthesis.
Iron deficiency: Even without overt anaemia, low ferritin levels affect dopamine metabolism and energy production in the brain. Iron deficiency is particularly common in menstruating women.
Chronic inflammation: Elevated inflammatory markers (IL-6, TNF-alpha, hsCRP) are consistently found in depression. Inflammation from gut dysfunction, autoimmune disease, chronic infection, or metabolic syndrome directly affects neurotransmitter metabolism and brain function.
Gut-brain axis dysfunction: Approximately 95% of serotonin is produced in the gut. Dysbiosis, intestinal permeability, and chronic gut inflammation can profoundly impact mood via the vagus nerve and inflammatory pathways.
Blood sugar dysregulation: Insulin resistance and reactive hypoglycaemia cause mood instability, irritability, and fatigue that closely mimic depression.
Hormonal imbalances: Low testosterone in men, oestrogen dominance or progesterone deficiency in women, and cortisol dysregulation can all present as depression.
Chronic infections: Epstein-Barr virus reactivation, Lyme disease, and other chronic infections can cause persistent fatigue and depression-like symptoms.
Why This Matters
If depression has a physical cause, treating it with antidepressants alone addresses the symptom without fixing the problem. This does not mean antidepressants have no role – they can be valuable and sometimes essential. But they work best when underlying physical contributors have been identified and addressed. Treating hypothyroidism, correcting vitamin D deficiency, or healing the gut can transform treatment outcomes.
Our Comprehensive Assessment
I evaluate every patient with depressive symptoms through a medical lens: complete thyroid panel, inflammatory markers, nutrient levels (B12, folate, iron, ferritin, vitamin D, zinc, magnesium, omega-3 index), blood sugar and insulin, sex hormones, cortisol, and liver function. When indicated, stool analysis and testing for chronic infections round out the picture.
What We Do: Treating the Whole Person
Correct identifiable deficiencies: Targeted supplementation of depleted nutrients, thyroid optimisation, and hormonal balancing.
Reduce inflammation: Anti-inflammatory diet, gut healing, omega-3 fatty acids, and addressing any sources of chronic inflammation.
Support neurotransmitter production: Ensuring the body has the building blocks (amino acids, cofactors, methylation support) needed to produce serotonin, dopamine, and GABA.
Integrated care: Collaborating with psychologists and psychiatrists when psychotherapy or medication is also indicated, ensuring a truly comprehensive treatment plan.
Conclusion
Depression is complex, and its causes are often multifactorial. A thorough physical evaluation should be a standard part of every depression assessment – yet it often is not. If you or someone you know is struggling with depression and has not had a comprehensive medical workup, I encourage you to book a consultation at our practice in Zürich Seefeld. Finding and treating physical causes can be truly life-changing.
