Achieving Personal Potential

What Is Functional Testing?

Beyond the thorough and comprehensive evaluation of a patient’s health history and current ailments via questionnaires, discussion and palpation, laboratory analyses are key to making thorough and in-depth investigations into someones health and the formulation of detailed health goals.

Functional Testing (FT) involves just what it sounds like, an assessment of how a certain region, aspect or mechanism of the body is functioning.

This commonly involves sampling and sending various body tissues (e.g. blood, stool, saliva, hair and urine) to a laboratory for analysis.

This provides a means of getting insights into current metabolic ‘function’ and processes, in a highly detailed and evidence-based way.

From this analysis critical information can be gathered about what precise disturbances that might be present on a biochemical level, which often guides a natural course of restoring and supporting natural function (and in the process ameliorating disease and imbalances).

This type of testing is key to:

  • Finding the true upstream causes for various symptoms (and future risks)
  • Demonstrating the inter-relationship of seemingly independent factors and systems (for comprehensive care)
  • Finding personalised insights to allow for customised treatments
  • Finding what is needed by the body, and what is not (excesses and deficiencies)

How Is FT Different From Standard Pathology Testing?

It is important to understand the difference between ‘Functional‘ Lab Testing and conventional medical ‘Pathology‘ Lab Testing.

Seeing as the word ‘pathology’ technically relates to the classification and diagnosis of disease, and the fact that Functional Testing is usually employed to detect personal imbalances and sub-optimal function rather than to diagnose, it may be more appropriate to reserve the word ‘pathology’ for standard medical testing alone.

Although the term ‘Functional Pathology Testing’ is still sometimes used (potentially as a hybrid of the two).

Functional Testing vs Pathology Testing

Pathology Testing
Functional Testing
Often used to ‘diagnose’Usually NOT diagnostic (focussed on imbalances)
Often suitable for emergency careUsually more suitable for managing chronichealth concerns
Usually analyses only one or few analytesOften analyses many analytes
Usually uses direct markers (measures levels)Often uses indirect markers (to determine functional needs)
Usually Interpreted QuantitativelyUsually Interpreted Qualitatively
Usually uses Reference Ranges to define a disease state (based on 95% of population)Uses patient’s unique factors, and the balance of key ratios to guide the relevance of results (as much as Reference Ranges)
Test result turnaround relatively rapidUsually longer time frame for test results
Lab method usually standardisedOften no standardisation between labs
Often relatively lower cost (usually simple to conduct – and commonly covered by government and private health insurance)Often higher cost (usually more complex, comprehensive and detailed – with minimal health insurance coverage)
Lab selection usually less relevantLab selection highly relevant


Whilst there are many ‘Functional Tests’ that are unique to Functional Medicine (and therefore not commonly used by Medical Practitioners), there are numerous medical ‘Pathology Tests’ that are regularly used by Functional Medicine practitioners (albeit in a functional, individualised and non-diagnostic way).

What Lab Tests Are Available?

There is a wide variety of Medical Pathology Lab Tests available, and potentially even more Functional Lab Tests.

The complexity of preparation procedures, costs, and also the possible insights that can be gained from each test, can all vary considerably.

For this reason all testing decisions should be well considered and rationalised (for a clear set of goals), and include full discussion and explanation with the patient.

The choice of test (and also quite crucially its interpretation) are a matter to discuss thoroughly between patient and practitioner.

Some common lab testing options include:

  • Comprehensive Blood Chemistry Panels: General metabolic parameters (Blood sugars, lipids, cells, enzymes, proteins, etc.)
  • Micronutrient Panels: Vitamins, Minerals, Amino Acids, Essential Fatty Acids, etc. (Blood, Urine)
  • Hormone Profiles: Adrenal Stress, Thyroid Function, Female & Male Hormone balance, Melatonin, etc. (Urine)
  • Digestive and GI Analysis: Stool testing for digestive function, infections, parasites, etc.
  • Food Allergy, Sensitivity & Intolerance Panels (Blood)
  • Chemical, Mould & Heavy Metal Toxin Panels (Urine, Hair)
  • Detoxification and Metabolic Efficiency Profiles (Urine Organic Acids)

Why Test?

Some of the reasons why laboratory testing is so crucial to effective clinical practice include:

1. Required to gain early and detailed insights. (that cannot be obtained any other way – and key to correct and early treatment)

2. Many imbalances can present no direct symptoms.

3. Excesses and deficiencies can often exhibit similarly (need to avoid potentially inappropriate treatments)

4. To avoid unnecessary / ‘guess work’ prescriptions (can be a very inefficient way of practicing – with mixed results)

5. To avoid ‘shotgun supplementation’ (and truly personalise supplementation e.g. via compounding)

6. To demonstrate the efficacy of long term risk strategies (that do not have immediate symptomatic feedback)

7. To provide objective reference points (e.g. before treatment and to monitor changes).

8. To provide tangibility and clarity (for motivation and compliance)

If you you would like to learn more about customising personalised medicines in response to laboratory test results, see Nutritional Compounding.

If you are (or would like to become) a Patient of Warren’s, personalised biochemical testing can assist with obtaining powerful insights into how your body is functioning, in order to tailor specific diet, supplement and lifestyle recommendations to your specific needs – see Patient applications and appointments here.