It Might Not Be Depression: Uncovering the Physical Conditions That Mimic Mental Illness

Why accurate diagnosis matters—and how root-cause care can change everything

Introduction: Are We Getting Depression Wrong?

Depression is one of the most commonly diagnosed conditions in medicine today. Millions of people are prescribed antidepressants every year, often after just a few minutes of discussion with a healthcare provider. But what if we’re missing the bigger picture?

At Movability, we see it all the time: patients who have been labeled with depression, placed on medications that come with side effects and withdrawal risks, yet continue to feel tired, foggy, and disconnected from themselves. These individuals aren’t necessarily struggling with a primary mood disorder—they’re often battling a misdiagnosed physical condition.

In cases where there’s no identifiable psychological trauma or life stressor, and the depression doesn’t respond to standard treatments, it’s essential to ask: What else could be going on in the body? This is where conventional care often stops, and where root-cause functional medicine begins.

How Physical Health Mimics Mental Illness: The Mind-Body Connection

The brain doesn’t exist in a vacuum. It relies on the health of your hormones, blood sugar, immune system, sleep cycle, gut microbiome, and nervous system to function properly. When any of these systems go off-track, mood changes often follow.

The pathophysiology is clear:

• Inflammation in the body can increase pro-inflammatory cytokines in the brain, leading to low mood and fatigue.

• Nutrient deficiencies impair neurotransmitter production, which affects motivation, cognition, and emotional regulation.

• Hormonal imbalances can destabilize serotonin and dopamine pathways.

• Sleep disruption causes reduced glymphatic clearance and dysregulation of stress hormones.

• Poor mitochondrial function and oxygen delivery impair brain energy metabolism, leading to “depression” that’s actually fatigue in disguise.

Overlooked Conditions That Can Mimic Depression

1. Hypothyroidism

Slowed metabolism from low thyroid function causes fatigue, brain fog, constipation, and low mood. Often misdiagnosed in women, especially postpartum or perimenopausal.

2. Vitamin B12 or D Deficiency

Both are critical for brain health. Deficiency leads to memory problems, poor concentration, low energy, and irritability.

3. Iron Deficiency Anemia

Lack of oxygen-carrying red blood cells causes exhaustion, reduced physical stamina, and feelings of hopelessness—often confused with depression.

4. Sleep Apnea

Interrupted sleep and chronic hypoxia lead to morning headaches, poor concentration, irritability, and anhedonia.

5. Insulin Resistance and Hypoglycemia

Blood sugar crashes cause mood swings, brain fog, and extreme fatigue. Many patients feel “tired but wired” with reactive low blood sugar.

6. PCOS (Polycystic Ovarian Syndrome)

This condition involves insulin resistance, inflammation, and excess androgens—all of which can influence neurotransmitters and contribute to mood symptoms.

7. Endometriosis

Beyond chronic pain and hormonal dysfunction, endometriosis is now linked to increased systemic inflammation and gut-brain axis disruption—both of which can impact mood.

8. Post-Concussive Syndrome

Following a mild traumatic brain injury, patients may experience fatigue, low mood, irritability, and memory issues for months to years—often labeled as depression or anxiety.

9. Chronic Infections (e.g., Lyme, EBV, Long COVID)

Persistent immune activation affects energy metabolism and nervous system regulation, leading to a “foggy, fatigued” version of depression that doesn’t respond to SSRIs.

10. Adrenal Dysregulation

Both low cortisol and a flat cortisol curve can cause feelings of burnout, apathy, low motivation, and emotional reactivity.

11. Gut Dysbiosis and SIBO

The gut produces more than 90% of serotonin precursors. Dysbiosis or bacterial overgrowth can alter brain chemistry through the vagus nerve and increase neuroinflammation.

12. Perimenopause and Hormonal Transitions

Estrogen affects serotonin sensitivity. As hormone levels fluctuate, mood instability, tearfulness, and sleep problems often surface—mistaken for primary mood disorders.

Why Standard Treatment Falls Short

In conventional care, a diagnosis of depression is often made based on a short symptom checklist. Labs are rarely ordered. Underlying causes like iron deficiency or thyroid dysfunction go untested, and physical symptoms (like fatigue or brain fog) are quickly interpreted as “psychosomatic.”

What’s more, once a patient begins an antidepressant, their ongoing fatigue, anxiety, or memory trouble is often blamed on the depression diagnosis itself—not on a missed root cause.

The result? Patients stay stuck on medications that may not work, can be difficult to stop, and were never designed to fix the real problem.

Movability’s Root-Cause Approach: Find the Signal Beneath the Noise

At Movability, we do things differently. We believe depression-like symptoms deserve a full investigation—not a surface-level label.

Our integrative, team-based approach includes:

• Comprehensive lab testing: thyroid panel, nutrient markers, inflammatory markers, hormone levels, blood sugar, ferritin, and more.

• Clinical correlation: physical exam findings, health history, and body systems mapping to connect symptoms to underlying dysfunction.

• Collaborative care: Our chiropractors, physiotherapists, naturopathic doctors, and internal practitioners work together to assess your neuroendocrine, metabolic, musculoskeletal, and emotional health.

• Personalized care plans: tailored treatment that may include dietary correction, supplementation, hormone rebalancing, physical rehabilitation, gut restoration, and nervous system support.

You won’t hear, “It’s just in your head” here. If something feels off, we believe you—and we dig until we find out why.

When to Suspect a Physical Mimic of Depression

You should consider testing for medical causes of depression-like symptoms if:

• Your symptoms started suddenly, without a clear emotional trigger.

• You have a history of thyroid, autoimmune, or hormonal issues.

• Your antidepressant isn’t helping, or you’re feeling worse on it.

• You’ve been told “everything is normal,” but still feel unwell.

• You feel constantly tired, foggy, or disconnected—even when life is going well.

• Your mood changes seem tied to your cycle, food, sleep, or physical pain.

Depression Isn’t Always Depression. And It’s Not Always in Your Head.

At Movability, we’ve helped countless patients who were misdiagnosed with depression uncover the real root cause of their symptoms—and reclaim their energy, clarity, and sense of self.

Whether it’s a nutrient deficiency, hormone imbalance, brain injury, or gut issue, we look at your whole system, not just your mood.

You deserve more than a prescription. You deserve answers.

Contact Movability today to book a comprehensive assessment and experience our results-driven approach.