Filaggrin, lipids, transepidermal water loss. Below: the plausible mechanism in plain language, then the
literature graded honestly — the strongest evidence here is
Grade A — and the functional tests
worth raising with a clinician.
The mechanistic link
Read through the functional lens, eczema is treated as a possible
downstream signal rather than the whole story. The
Skin Barrier system enters the picture because filaggrin, lipids, transepidermal water loss. Each link below is a hypothesis to discuss, never a
diagnosis or a cure claim, and every page clears a human review gate
before it is published.
The evidence
What the literature actually supports.
Each statement carries an A–D strength badge and resolvable
citations. Grades describe how strong the underlying research is —
never whether something is good or bad for you.
How to read the grades →
Filaggrin loss-of-function variants are among the strongest established risk factors for atopic eczema: they impair the skin's water-retaining envelope, raising water loss and easing allergen and microbial entry.
“Filaggrin null mutations conferred a consistently elevated risk of atopic dermatitis across pooled cohorts in this meta-analysis.”
Elevated transepidermal water loss is a measurable hallmark of the eczema barrier defect and tracks with disease severity; it is also seen in clinically normal-looking skin of affected people, suggesting a trait-level vulnerability.
Citations are stable corpus references; resolvable outbound links land
with the literature pipeline (Epic C). These entries are fixtures
until Epic D generates reviewed content.
IFM Matrix anchor
Structural Integrity
Structural Integrity is the IFM node for the integrity of membranes and barriers — at the skin, the filaggrin–lipid envelope whose breakdown raises transepidermal water loss.
Each system maps to a node on the IFM Functional Medicine Matrix; the
full mapping and its limitations live on the
methodology page →
Tests for this system
What you could actually ask to measure.
Functional and conventional tests that probe the skin barrier
link for eczema. Findings are cited and graded; some require
more than one biomarker read together.
Skin barrier function assessment
Conventional or functional
How well the outer skin barrier holds water and resists colonisation — instrument-measured water loss, plus a filaggrin genotype and a skin-microbiology swab.
Higher transepidermal water loss reflects a weaker barrier and predicts greater eczema severity and flare risk — among the better-replicated barrier findings.
A filaggrin loss-of-function variant carried alongside high Staphylococcus aureus skin colonisation marks a barrier-plus-colonisation phenotype that tends to track with more persistent disease — a multi-biomarker combination, hypothesis-level for now.
Grade Dabstract-level: Early — hypothesis / expert opinionfixture-flg-staph-phenotype-2022
Take it to your appointment
The Skin Barrier test checklist for eczema.
A free, citation-backed one-pager of the skin barrier
tests above — what each measures and the findings to discuss
— so the conversation with your clinician starts informed.