16 October

Acne Root Cause Testing: routine testing recommended by Naturopaths at Guided by Tradition

Acne isn’t a skin condition — it’s a symptom of something happening elsewhere in the body. Topical treatments can manage the surface, but if the underlying driver (hormonal, metabolic, inflammatory, or gut-related) isn’t identified, breakouts tend to return. As a naturopath, my approach to persistent or cystic acne always starts with testing, not guessing. Below is an overview of the key markers I investigate to uncover what’s actually driving your skin.

Thyroid Testing (Comprehensive Panel)

The thyroid regulates metabolism, hormone clearance, and skin cell turnover — so even subclinical thyroid dysfunction can show up as congested, slow-healing, or inflamed skin. Unfortunately, a standard TSH-only test often misses the full picture.

A comprehensive thyroid panel should include:

TSH (thyroid stimulating hormone)
Free T4 and Free T3 (the active thyroid hormones)
Thyroid antibodies (TPO and TG) to rule out autoimmune thyroid conditions like Hashimoto’s

When testing the thyroid, optimal pathology ranges need to be used, instead of the standard lab ranges that are looking out for ‘disease’ and not ‘subclinical’ pictures – see my blog on optimal ranges for more information on this topic.

Undiagnosed thyroid imbalances can contribute to poor detoxification of excess hormones, sluggish circulation, and dry and/or reactive skin — all of which can worsen acne.

Blood Sugar and Insulin Testing

Blood sugar dysregulation is one of the most overlooked contributors to acne, particularly hormonal and jawline acne. High insulin levels stimulate androgen production and increase oil (sebum) production, directly feeding breakouts.

Useful markers include:

Fasting glucose
Fasting insulin
HbA1c (average blood sugar over 2–3 months)

Testing insulin alongside glucose is essential — many people have “normal” blood sugar but elevated insulin, a sign of early insulin resistance that glucose alone won’t catch.

Also, it is essential to use an optimal fasting insulin range – which is 4-6.. Interestingly, ‘normal’ fasted insulin reference ranges increased from needing to be under 10, to being under 25 a few years ago – this is due to Australia having an issue with obesity and diabetes, affecting the ‘average’ level provided by labs.

Nutrient Status Testing

Several key nutrients are directly involved in skin healing, oil regulation, and inflammation control. Deficiencies — even mild ones — can perpetuate breakouts.

Zinc — supports immune function and has anti-inflammatory, oil-regulating effects on the skin
Copper — tested alongside zinc, as imbalances in the zinc-to-copper ratio can affect skin healing
Iron (ferritin) — low iron stores are linked to poor wound healing and fatigue that compounds stress-driven breakouts
Vitamin D — plays a role in immune regulation and skin barrier function
Folate — important for cell turnover and methylation, which affects hormone clearance

Inflammatory Markers

Acne is fundamentally an inflammatory condition, so understanding your baseline inflammatory load can reveal how much of your acne is being driven by systemic inflammation rather than purely hormonal or bacterial causes.

ESR (erythrocyte sedimentation rate)
CRP (C-reactive protein)
Homocysteine — elevated levels can indicate impaired methylation, which affects both detoxification and inflammation

White Cell Count and Immune Function

A full blood count, specifically white cell count, can offer clues when acne is severe, recurrent, or unusual in presentation. If immune function is compromised, the body may struggle to control the bacteria naturally present on the skin, leading to more frequent or harder-to-resolve breakouts.

Stool Testing and Gut Health

The gut-skin axis is well established — imbalances in gut bacteria, pathogens, or poor digestive function can all drive systemic inflammation that shows up on the skin. Stool testing can identify:

Dysbiosis (imbalanced gut flora)
Pathogenic bacteria, parasites, or yeast overgrowth
Markers of gut inflammation or poor digestion

For clients with concurrent digestive symptoms (bloating, irregular bowel movements, food sensitivities), stool testing is often one of the most revealing pieces of the puzzle.

Hormone Saliva Testing for Estrogen Dominance

Saliva hormone testing is particularly useful if you notice:

Heavy or painful periods
Cystic acne that worsens around ovulation and throughout the luteal phase
A diagnosis of endometriosis, adenomyosis, or fibroids

This type of testing maps hormone levels (often estrogen and progesterone) across the cycle, rather than relying on a single snapshot. This can help identify estrogen dominance relative to progesterone — a common but often missed driver of cyclical, hormonal acne.

Skin Swabs for Bacterial Causes

While most of the testing above addresses internal, root-cause drivers, a skin swab serves a different purpose — identifying localised bacterial involvement. If acne lesions are unusually inflamed, slow to heal, or not responding to typical approaches, a swab can determine whether Staphylococcus or Streptococcus species are present and guide more targeted treatment.

Bringing It Together — Why Testing Matters More Than Guessing

Acne rarely has a single cause — which is why testing across these systems (thyroid, blood sugar, nutrients, inflammation, immune function, gut health, and hormones) gives a far more complete picture than treating the skin in isolation. If you’ve tried countless creams and routines without lasting results, the answer may lie in what’s happening beneath the surface.