Functional Medicine: Finding the “Why” Behind Chronic Illness

Author: Rohan Smith | Functional Medicine Practitioner | Adelaide, SA

In our Adelaide clinic at Elemental Health and Nutrition, many patients describe persistent fatigue, pain, or physiological imbalance despite being told their blood tests fall “within normal range.” While conventional medicine plays a critical role in acute care and disease management, chronic conditions frequently involve multi-system dysfunction that may not reach diagnostic thresholds on standard pathology.

Functional Medicine is a systems-based, evidence-informed approach that aims to identify contributing physiological drivers of chronic symptoms, rather than focusing solely on isolated clinical findings.

Quick Answer: What Is Functional Medicine?

Functional Medicine is a whole-person, systems biology approach that examines how genetics, environment, nutrition, lifestyle, and psychosocial stressors interact to influence health outcomes. Instead of centring care around disease labels alone, it evaluates patterns of dysfunction across interconnected body systems and seeks to address upstream contributors where clinically appropriate (1–4).

Moving Beyond a Symptom-Only Model

Chronic illness rarely arises from a single isolated abnormality. Research into complex disease models suggests that persistent symptoms often reflect interacting metabolic, immune, hormonal, and neurological stressors, rather than a single discrete pathology (3,5).

In clinical education, commonly cited examples include:

• Lipid-lowering therapy improving cholesterol markers without addressing metabolic contributors such as insulin resistance or inflammatory signalling
• Short-term digestive symptom relief without identifying contributing factors such as microbial imbalance, nutrient insufficiency, or immune activation

Functional Medicine applies structured clinical questioning to explore why dysfunction may be occurring, while remaining complementary—not oppositional—to conventional medical care (2,4).

Common Contributing Drivers Explored in Chronic Illness

• Mitochondrial and Energy Metabolism: Altered cellular energy production has been associated with fatigue-dominant conditions, including presentations seen in chronic fatigue and unexplained symptoms (6,7).
• Environmental and Toxicant Exposure: Certain environmental factors may contribute to oxidative stress and impaired detoxification capacity in susceptible individuals (8,9).
• Gut Function and Microbiome Balance: Changes in intestinal permeability and microbial composition have been associated with immune and inflammatory processes, as discussed further in our overview of gut dysfunction and microbiome imbalance (10–12).
• Hormonal Regulation: Dysregulation of insulin, thyroid hormones, and the hypothalamic–pituitary–adrenal (HPA) axis may influence metabolic stability and stress resilience, including patterns seen in thyroid and hormonal dysfunction (13–15).
• Psychophysiological Stress Load: Chronic stress exposure has been linked to autonomic imbalance and inflammatory signalling via neuroendocrine pathways (16–18).

Clinical Pattern Recognition: Asking Better Questions

Functional Medicine emphasises pattern recognition over symptom isolation. Observations are used to guide further investigation, not to establish diagnoses in isolation.

• Zinc status: Zinc plays a role in immune signalling, digestion, and enzymatic activity; suboptimal intake or absorption may contribute to dysfunction in some individuals (19,20).
• Vitamin B12 and neurological function: B12 insufficiency has been associated with fatigue, balance disturbances, and neurocognitive symptoms, particularly in at-risk populations (21,22).
• Oxalate handling: In selected clinical contexts, impaired oxalate metabolism has been discussed in relation to renal and musculoskeletal symptoms, though evidence remains evolving (23,24).

Advanced Functional Testing (When Clinically Indicated)

When appropriate, Functional Medicine practitioners may utilise validated specialty testing alongside standard pathology to explore functional patterns, including:

• Comprehensive stool analysis for digestive and microbial markers (10–12)
• Environmental exposure screening when clinical history suggests potential relevance (8,9)
• Organic acids testing (OAT) to assess metabolic intermediates related to energy production and nutrient pathways, such as organic acids testing (6,7,25)

Testing is selected based on clinical relevance and is not used as a stand-alone diagnostic tool.

Next Steps

If persistent symptoms remain unexplained despite standard care, a structured Functional Medicine assessment may help clarify contributing physiological patterns.

Key Insights

• Functional Medicine explores upstream contributors, not only downstream symptoms
• Chronic illness commonly reflects multi-system interaction, rather than single-cause pathology
• Care is individualised, evidence-informed, and complementary
• Advanced testing is applied selectively and contextually

Ready to Explore Contributing Factors?

If you are experiencing persistent symptoms despite “normal” results, a Functional Medicine approach may help clarify what is being missed.

Book a Functional Medicine Discovery Session with Rohan Smith at Elemental Health and Nutrition.

References

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