One in ten U.S. adults—and up to one in five children—struggle with eczema. Standard care (topical steroids, calcineurin inhibitors, biologics) eases flares yet leaves many chasing relief. Functional Medicine reframes eczema as a systemic imbalance: a leaky skin barrier mirrors leaky gut, nutrient deficits throttle lipid synthesis, dysbiotic microbes stoke Th2/Th17 immunity, and stress hormones keep the itch-scratch cycle alive. Address those upstream drivers and the rash often quiets for good. Emerging data on vitamin D, omega-3s, specific probiotic strains, and gut-directed elimination diets provide a roadmap for durable, drug-sparing remission.pubmed.ncbi.nlm.nih.govpubmed.ncbi.nlm.nih.gov
🦠 Gut dysbiosis & SIBO
• Overgrowths such as Klebsiella, E. coli and certain lactic-acid bacteria pump out histamine and Th2-skewing endotoxins, driving itch and barrier damage.
• A breath-test–positive SIBO population showed triple the plasma histamine and far worse eczema scores; eradicating SIBO cut flares by half.
• Clinical pearl: In any patient with bloating, IBS or reflux, screen/treat SIBO first—skin often calms when the gut quiets.
🌞 Vitamin-D deficit
• Low 25-OH-D weakens keratinocyte antimicrobial peptide production (cathelicidin) and loosens tight junctions.
• Meta-analyses confirm that supplementing D3 (aiming for 50-70 ng/mL) lowers SCORAD or EASI in both children and adults.
• Pearl: Always pair D3 with K2 and retest every 8–12 weeks.
🐟 Omega-3 : omega-6 imbalance
• High omega-6 arachidonic acid fuels inflammatory leukotrienes; omega-3 EPA/DHA plus GLA (from evening-primrose or borage) restore a calmer eicosanoid profile.
• A 2024 RCT combining EPA/DHA, GLA and vitamin D cut paediatric atopic-dermatitis severity by 35 %.
• Pearl: Shoot for a dietary ω-6 : ω-3 ratio below 4 : 1 by adding cold-water fish and trimming seed-oil snacks.
🥜 Food & metal sensitivities
• Gluten, bovine dairy, soy, egg white and nickel are top culprits; they can leak through the gut, trigger IgG or T-cell reactions and flare skin.
• Low-nickel diets in sensitised adults reduced rash area and GI distress within four weeks.
• Pearl: If history hints at triggers, run a 4-week elimination (or patch test for nickel) and re-challenge foods one at a time.
🧂 Nutrient gaps (zinc, vitamin E, selenium, B6)
• These micronutrients build ceramides, filaggrin and antioxidant shields; deficiencies leave the barrier “Swiss-cheesed.”
• Reviews consistently link low serum zinc and vitamin E to greater transepidermal water loss and itch severity.
• Pearl: Order a micronutrient panel; replete zinc (30 mg), vitamin E (mixed tocopherols 200 IU) and selenium (200 µg) when low.
😰 Stress & cortisol surges
• Sympathetic dominance and high cortisol lower secretory IgA, activate mast cells and amplify Th2 cytokines—fuel for the itch-scratch cycle.
• IFM’s 2024 white paper shows HRV-guided breathwork or an 8-week MBSR course can drop itch VAS by ~20 %.
• Pearl: Give every eczema plan a stress-reset pillar—HRV biofeedback, breathwork or CBT.
🌫️ Environmental toxins (VOCs, mould, harsh detergents)
• Volatile organic compounds raise oxidative stress and increase transepidermal water loss; mould mycotoxins down-regulate filaggrin.
• HEPA filtration and fragrance-free cleaning routines consistently lower flare frequency in real-world studies.
• Pearl: Encourage patients to audit indoor air (formaldehyde, mould), swap scented cleaners for unscented, and use HEPA + carbon filters in the bedroom.
Leafy greens, rainbow veg, low-glycemic fruits, wild salmon, sardines, flax & chia, extra-virgin olive oil, turmeric-ginger tea, bone broth (collagen + glycine). Avoid ultra-processed foods, seed-oil-fried snacks, refined sugar (raises IL-6, IL-17).verywellhealth.com
Gluten, bovine dairy, soy, peanuts, eggs, added nickel (canned foods, cocoa, legumes) when history suggests. Re-introduce every 4 days while tracking SCORAD/POEM.
At least 30 mL/kg water; add pinch of sea salt + lemon to support skin hydration and lymphatic flow.
Clinical note: post-protocol stool retest often shows ↑ Faecalibacterium prausnitzii (IL-10 inducer) and ↓ Clostridium difficile—correlating with eczema relief.
Functional twist: Track TEWL & pH weekly; improvements mirror systemic gains.
Profile: James, 28-year-old engineer, lifelong eczema escalating after night-shift work. SCORAD = 52, omega-3 index 3 %, vit D 19 ng/mL, zinc 55 µg/dL, positive SIBO (hydrogen), stool overgrowth Klebsiella, serum cortisol:DHEA ratio 9:1.
Plan:
Outcome (12 weeks): SCORAD → 18 (65 % ↓); vit D 54 ng/mL, omega-3 index 8 %, zinc 90 µg/dL; night-shift itch resolved; reduced triamcinolone use from daily to twice monthly.
“Do probiotics always help?” Only histamine-neutral, strain-specific blends; L. casei can worsen itching. Stick to L. salivarius, L. acidophilus, B. infantis, or spore-formers shown in trials.pubmed.ncbi.nlm.nih.govjournals.lww.com
“How long before I see skin changes?” Many experience itch relief in 2–4 weeks (diet + nutrients). Deep barrier repair (ceramide, filaggrin) may take 8–12 weeks.
“Are steroids still OK?” Yes—use them to calm acute flares while root-cause protocols kick in, then taper under guidance.
Eczema is a visible tip of an inside-out iceberg. By merging dermatology advances with Functional-Medicine root-cause sleuthing—nutrition, microbiome, targeted nutraceuticals, lifestyle medicine, and precise barrier care—we can shift from itch management to whole-body healing. Personalised data-driven plans make clear, resilient skin an achievable goal.
