Eczema (Atopic Dermatitis): A Nutrition and Natural-Health Reference
1. Definition and Nomenclature
Eczema, or atopic dermatitis, is the most common form of dermatitis. It is a chronic, relapsing inflammatory skin disorder characterized by dry skin, localized erythematous rash, and intense pruritus. The word "eczema" derives from the Greek ekzein ("to boil out") and has been used historically to describe a broad spectrum of inflammatory skin presentations, while the more specific term "atopic dermatitis" (AD) entered widespread clinical use in the late twentieth century.
The term "eczema" is applied to skin features seen in conditions such as childhood eczema, flexural eczema, infantile eczema, dyshidrotic eczema, and nummular eczema, while "dermatitis" is conventionally used for named disease entities such as contact dermatitis and seborrheic dermatitis. Eczema is best understood as a constellation of clinical findings rather than a single disease, and may manifest with erythema, papules, vesicles, crusts, weeping, and edema in its acute phase, and with thickening of the skin, lichenification, and scaling in its chronic phase; itching is a guiding symptom. The terms "dermatitis" and "eczema" are often used interchangeably, though some authors reserve "dermatitis" for acute inflammatory lesions and "eczema" for chronic epidermal lesions with hyperkeratosis.
The global prevalence of AD has been increasing over the past decades, affecting over 20% of children and 10% of adults worldwide. The 2019 Global Burden of Diseases data recorded 171 million cases of AD worldwide, representing a 28.6% increase in prevalence since 1990.
2. Clinical Presentation
Atopic dermatitis, often referred to as eczema, is a chronic (long-lasting) disease that causes inflammation, redness, and irritation of the skin. It is a common condition that usually begins in childhood; however, anyone can get the disease at any age. In most cases, there are periods of time when the disease is worse, called flares, followed by periods when the skin improves or clears up entirely, called remissions.
People with eczema tend to have dry, itchy skin prone to infection. The condition is commonly known as the "itch that rashes" because dry, itchy skin leads to a rash due to scratching or rubbing the skin. Atopic dermatitis causes the skin to become extremely itchy. Scratching leads to further redness, swelling, cracking, "weeping" clear fluid, crusting, and scaling.
The clinical manifestations are variable and age dependent. Infants typically develop lesions on the face and scalp; older children more often present with involvement of the flexural areas (antecubital and popliteal fossae); adults may display widespread or localized involvement. Atopic dermatitis usually develops in infancy and is characterized by pruritus, dry skin, eczematous lesions, and lichenification.
The condition is believed to coexist with other immunoglobulin E (IgE)–associated disorders, including allergic rhinitis, asthma, and food allergies. The onset of AD occurs primarily in childhood and is thought to precede allergic disorders mediated by an immunoglobulin E (IgE) sensitization to environmental antigens, namely, asthma and allergic rhinoconjunctivitis — the so-called atopic march.
3. Body Systems Involved
3.1 The Skin Barrier
The complex interplay among skin barrier deficiency, immunological derangement, and pruritus contributes to the development, progression, and chronicity of the disease. Abnormalities in filaggrin, other stratum corneum constituents, and tight junctions induce and/or promote skin inflammation. This inflammation, in turn, can further deteriorate the barrier function by downregulating essential barrier-maintaining molecules.
AD is a chronic inflammatory skin disease characterized by a compromised epidermal barrier and heightened immunoglobulin E (IgE) levels, often associated with filaggrin (FLG) gene mutations. The filaggrin gene, responsible for encoding a protein that supports skin barrier integrity and function, is often mutated in patients that present with atopic dermatitis. The skin uses filaggrin metabolic byproducts to produce factors essential for skin hydration and skin microbial balance. Mutations in filaggrin may lead to increased epidermal barrier permeability and the deeper passage of allergens, contributing to immune responses. Lipid depletion of the stratum corneum may affect skin permeability and increase sensitization to allergens. The depletion of ceramides — lipids found in the stratum corneum responsible for regulating skin hydration and providing antimicrobial activity — is linked to the pathogenesis of atopic dermatitis.
Alterations in structural proteins, lipids, proteases, and their inhibitors lead to the impairment of the stratum corneum, which is associated with increased skin penetration and transepidermal water loss.
3.2 The Immune System
Skin-resident cells, including keratinocytes and many immune cells, are crucial in driving inflammatory responses in AD. Immune cells such as T lymphocytes, plasmacytoid dendritic cells, monocytes, and granulocytes that migrate from the bloodstream further contribute to the development of eczema. Although these immune cells interact in a highly complex manner, the immunopathogenesis of AD is primarily driven by a Th2-dominant immune response.
AD is a chronic or chronically relapsing, eczematous, severely pruritic skin disorder mostly associated with IgE elevation and skin barrier dysfunction due to decreased filaggrin expression. The lesional skin of AD exhibits Th2- and Th22-deviated immune reactions that are progressive during disease chronicity. Th2 and Th22 cytokines further deteriorate the skin barrier by inhibiting filaggrin expression. Upon activation of the ORAI1 calcium channel, atopic epidermis releases large amounts of thymic stromal lymphopoietin (TSLP), which initiates the Th2 and Th22 immune response. Th2-derived interleukin-31 and TSLP induce an itch sensation.
Elevated serum immunoglobulin E levels and blood eosinophilia have been shown in the majority of AD patients. Type 2 T-helper cell immune pathway with increased expression of interleukin (IL)-4, IL-5, and IL-13, has an important role in the etiopathogenesis of AD.
3.3 The Skin Microbiome
Atopic dermatitis is a complex and heterogeneous disease affected by a variety of factors, including host genetics, altered skin barrier function and structure, immunological abnormalities, and environmental factors, including exposure to specific pathogens such as Staphylococcus aureus. Specific strains of other microbes within the community of resident skin bacteria suppress inflammation, stimulate the adaptive and innate immune system, and produce diverse molecules with antimicrobial activity. These actions of the microbial community are essential to maintain cutaneous homeostasis and defend against pathogenic microorganisms.
Particularly during an acute phase, a strongly reduced bacterial diversity as well as the dominance of a single pathogen, Staphylococcus aureus, is observed. Staphylococcus aureus exacerbates the inflammatory process. In patients with AD, a decrease in microbiome diversity correlates with disease severity and increased colonization with pathogenic bacteria, such as S. aureus.
Early clinical studies suggest that topical application of commensal organisms (e.g., Staphylococcus hominis or Roseomonas mucosa) reduces AD severity, which supports an important role for commensals in decreasing S. aureus colonization in patients with AD.
3.4 The Gut-Skin Axis
The relationship between the intestinal microbiome and the development of atopic disease is an active area of research. One prospective cohort study analyzed fecal samples and allergy status in 21 allergic infants (with eczema and/or allergic rhinitis) and 18 healthy controls at 18 months. The authors found that infants who later developed allergies had lower Bifidobacteria and higher Klebsiella levels at 3 months of age compared to infants who remained healthy. A higher Klebsiella/Bifidobacterium ratio at 3 months was linked to a greater risk of allergic diseases by age 3 years.
Probiotics are a treatment that may alter the intestinal microbiota of people with eczema. Probiotics are live micro-organisms (e.g., Lactobacillus species) that when administered in adequate amounts confer a health benefit on the host. Their precise mode of action is not well established, but they have been shown to reduce markers of intestinal inflammation and intestinal permeability in disease states. This might change the way in which antigens present in the intestine are recognised by the immune system.
4. Contributing and Associated Factors
4.1 Genetic Factors
There is a strong genetic component to eczema, with a family history of eczema, asthma, or allergies commonly found in affected individuals. Several genes associated with eczema have been identified, including those involved in the skin barrier function and the immune system. Genetic factors like FLG mutations and environmental influences, including microbial exposure and pollutants, contribute to the disease's progression, leading to itchy, inflamed skin.
4.2 Environmental Triggers
Environmental triggers are diverse and include irritants like soaps, detergents, and disinfectants, as well as allergens such as pollen, pet dander, dust mites, mold, and certain foods.
4.3 Psychological Stress
Psychological stress is a significant environmental factor influencing the course of AD, a chronic inflammatory skin condition marked by pruritus and recurrent eczematous lesions. AD is influenced by genetic, immunological, psychological, and environmental factors including the skin microbiome. The mechanisms by which stress worsens AD are thought to be multifactorial, involving neurogenic inflammation and immune skewing. Pruritus in AD, which may be due to hyperinnervation of the epidermis, increases pruritogens, and central sensitization compromises the skin integrity and promotes inflammation.
4.4 Hygiene Hypothesis and Early-Life Exposures
Atopic dermatitis is associated with considerable morbidity, and its prevalence has been increasing over the past few decades. The increasing prevalence of AD has been linked in part to changes in early-life microbial exposure, sometimes discussed under the "hygiene hypothesis." As one of the most common skin disorders globally, atopic dermatitis poses a significant clinical and economic burden on affected patients.
4.5 Atopic Comorbidities
As one of the most common skin disorders globally, the effects of AD are not limited to the intense pruritus that characterizes eczematous lesions but are associated with risks of other systemic disease, including progression to other allergic comorbidities. Children with eczema are more likely to develop other atopic conditions such as asthma, rhinitis, and food allergies. Though distinct, these disorders have common genetic risk factors and environmental triggers.
5. Nutrients, Herbs, and Natural Ingredients
The following sections separate traditional use — recorded historical or ethnobotanical practice — from scientific evidence, which is graded for study type and strength. A 2023 systematic review published in JMIR Dermatology that searched PubMed, Scopus, and MEDLINE (1993–2023) and included 18 studies involving 881 patients concluded that overall, there is weak evidence to support any one nutritional supplement intervention for the alleviation of AD symptoms, though multiple trials showed promise for specific interventions, and the most evidence was found for the effectiveness of probiotics on the clinical course of AD.
5.1 Vitamin D
Overview: Vitamin D is a fat-soluble secosteroid synthesized in the skin upon ultraviolet B exposure and also obtained from dietary sources. It has multiple immunomodulatory and barrier-supportive roles.
Scientific Evidence: Vitamin D has received the most consistent research attention of any single micronutrient in AD. A 2014 randomized, double-blind, placebo-controlled trial published in the Journal of Allergy and Clinical Immunology tested vitamin D3 at 1,000 IU/day for one year in 116 children with AD. Results showed significantly reduced SCORAD index scores and lower rates of flares compared to placebo. A 2016 Iranian RCT using 1,600 IU/day for 60 days found statistically significant SCORAD improvement in adults with moderate AD. A 2020 meta-analysis of 9 RCTs in the Journal of Dermatological Treatment found that vitamin D supplementation significantly reduced SCORAD severity scores in AD patients compared to placebo.
A systematic review and meta-analysis published in Evidence-Based Complementary and Alternative Medicine (2019), searching PubMed, Embase, and Cochrane (through January 2019) and including 10 RCTs with 456 patients, found that compared to controls, the SCORAD index or EASI decreased in the vitamin supplement group (mean difference −5.96, 95% CI: −7.69 to −4.23 for vitamin D3). This study suggests that vitamin supplements could be important therapeutics to help manage eczema patients.
A separate systematic review drawing on 45 RCTs (4,127 patients across 18 countries, published through October 2023) found moderate evidence for vitamin D supplementation improving the SCORAD index in deficient patients (mean difference −6.2, 95% CI −10.1 to −2.3; p=0.002). Omega-3 fatty acids and zinc showed no clinically meaningful benefits in that review. The authors concluded that evidence for most supplements remains low-quality, with vitamin D being the only intervention showing statistically significant but context-dependent effects.
Evidence strength: Moderate, derived from multiple RCTs and meta-analyses. Evidence is most consistent when baseline vitamin D status is low. Results across trials are not entirely uniform, reflecting variation in dosing, duration, and population.
5.2 Omega-3 Fatty Acids (Fish Oil / EPA and DHA)
Overview: Omega-3 polyunsaturated fatty acids (PUFAs), principally eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are found in fatty fish and marine oils.
Proposed mechanism: EPA and DHA from fish oil compete with arachidonic acid (AA) for incorporation into cell membrane phospholipids. Replacing AA with EPA shifts the balance of eicosanoids produced during inflammation toward less inflammatory series-3 prostaglandins and series-5 leukotrienes, reducing the intensity of the inflammatory cascade in AD.
Scientific Evidence: The evidence base for oral omega-3 supplementation in AD is mixed. The evidence for fish oil in AD is mixed. A 2012 Cochrane review of fish oil and EPO for eczema found insufficient evidence to recommend either. The Cochrane review on dietary supplements for established atopic eczema (Bath-Hextall et al., 2012), which included 11 RCTs with 596 participants, examined fish oil among other interventions; two of the 11 studies assessed fish oil versus olive oil or corn oil placebo, alongside zinc sulphate, selenium, vitamin D, vitamin E, pyridoxine, sea buckthorn oil, hempseed oil, and DHA as individual comparisons. The review did not identify adequate evidence to recommend any single supplement definitively. In a more recent randomized controlled trial, a product containing omega-3 fatty acids, omega-6 fatty acids, and vitamin D improved a range of clinical outcomes in young children with atopic dermatitis.
Evidence strength: Preliminary to mixed. Individual trials show benefit; pooled data remain inconsistent. The combination of omega-3s with vitamin D may be more promising than omega-3s alone, but further adequately powered RCTs are needed.
5.3 Evening Primrose Oil and Borage Oil (Gamma-Linolenic Acid / GLA)
Traditional use: Evening primrose oil (EPO) has been used for centuries to support hormonal balance, treat various skin conditions, and relieve symptoms related to menopause and PMS. Its application to inflammatory skin conditions, including eczema, became particularly popular from the early 1980s onward, based on the premise of a potential deficiency in the conversion of linoleic acid to GLA in atopic individuals.
Botany and composition: Evening primrose is a plant native to North and South America that also grows throughout Europe and parts of Asia. Evening primrose oil is extracted from the seeds of the Oenothera biennis plant. The oil is most notable for its high content of gamma-linolenic acid (GLA), an omega-6 fatty acid that plays a crucial role in maintaining the health of skin cells and reducing inflammation. Borage oil (Borago officinalis) contains an even higher proportion of GLA than EPO.
Scientific Evidence: The most comprehensive evidence assessment comes from a Cochrane systematic review (Bamford et al., 2013) of oral EPO and borage oil for eczema. The review included 27 studies, with 1,596 adults and children from 12 countries. Of these, 19 studies compared EPO with a placebo and 8 used borage oil compared with placebo. All 27 studies evaluated overall improvement of eczema, but only 2 studies of EPO measured improvement in quality of life. There was no statistically significant advantage demonstrated for either EPO or borage oil compared to placebo.
The Cochrane review concluded that oral borage oil and evening primrose oil lack effect on eczema; improvement was similar to respective placebos used in trials. The Cochrane authors stated that there is no evidence that taking either evening primrose or borage oil is of benefit to eczema sufferers.
Evidence strength: Negative at this time. The most rigorous and comprehensive evidence review (Cochrane, 27 RCTs, 1,596 participants) found no clinically meaningful benefit for oral GLA supplementation in eczema over placebo.
5.4 Probiotics and Prebiotics
Traditional and historical context: Fermented foods containing live bacterial cultures have been consumed across cultures for millennia, though their use specifically for inflammatory skin conditions is a modern extrapolation from this tradition rather than a documented historical practice.
Scientific Evidence: Probiotics have received substantial research attention for both the prevention and treatment of AD. The most evidence within nutrition supplement research for AD was found on the effectiveness of probiotics on the clinical course of AD.
For prevention: A strong body of evidence supports the benefits of extensively hydrolyzed casein formula (EHCF) supplemented with Lactobacillus rhamnosus GG (LGG). Several large clinical trials consistently showed that EHCF + LGG reduced the incidence of other allergic manifestations (eczema, asthma, urticaria, rhinoconjunctivitis) and accelerated the acquisition of immune tolerance to cow's milk proteins.
For treatment: Probiotics showed inconsistent results in systematic review, with only specific strains (e.g., Lactobacillus rhamnosus GG) demonstrating modest efficacy in pediatric AD (p<0.05 in 3 of 12 trials). The probiotic evidence is most robust for prevention in high-risk infants and children. For adult treatment, results are more variable. A meta-analysis of 6 RCTs found that probiotics significantly reduced eczema severity in adults, with SCORAD scores dropping by an average of 7.9 points, and quality of life improving as well.
For prebiotics: A systematic review in 2013 examined whether prebiotics given to infants could prevent infant sensitization to dietary allergens. The authors concluded that prebiotic supplementation could potentially prevent eczema in infants up to two years of age; however, neonatal prebiotic supplementation did not prevent the development of food allergies.
Evidence strength: Moderate for prevention in high-risk infants, particularly with L. rhamnosus GG. Mixed and strain-dependent for treatment. Adult data are more limited. Heterogeneity across trials (strains, doses, populations, durations) limits firm conclusions.
5.5 Vitamin E
Traditional context: Vitamin E (tocopherol) has long been included in topical skin preparations for its antioxidant properties. Oral supplementation in atopic conditions is a more recent area of study.
Scientific Evidence: The 2019 systematic review and meta-analysis of vitamin supplements in eczema found that compared to controls, the SCORAD index or EASI decreased with vitamin E supplementation (mean difference −5.72, 95% CI: −11.41 to −0.03). However, the wide confidence interval indicates substantial uncertainty. Previous studies have suggested that vitamins, including vitamin E, may be useful in the treatment of atopic eczema; however, more evidence is needed before vitamin supplements can be recommended.
Evidence strength: Preliminary. The effect observed in the meta-analysis is based on a small number of trials with wide confidence intervals.
5.6 Vitamin B12 (Topical)
Scientific Evidence: Topical vitamin B12 (cyanocobalamin) has been examined in small studies. The 2019 meta-analysis of vitamin supplements in eczema included RCT data for topical B12 and found a mean difference in SCORAD of −3.19 (95% CI: −4.27 to −2.10) for vitamin B12, indicating a modest reduction in severity scores. Evidence remains limited to small trials.
Evidence strength: Preliminary, based on few small RCTs.
5.7 Zinc
Traditional context: Zinc oxide has been used topically in dermatological preparations for centuries and remains a standard ingredient in barrier creams.
Scientific Evidence: In the 45-RCT systematic review (4,127 AD patients), zinc showed no clinically meaningful benefits. The Cochrane review of dietary supplements for established atopic eczema included a comparison of oral zinc sulphate compared to placebo among its evaluated interventions, without identifying robust benefit. Zinc supports normal immune signaling and skin repair at a fundamental level. Correcting a true deficiency may help restore balance.
Evidence strength: Insufficient evidence to support routine oral zinc supplementation in AD. Correction of documented deficiency may be relevant on general nutritional grounds.
5.8 Colloidal Oatmeal (Avena sativa)
Traditional use: Oat preparations (Avena sativa) have been used topically since antiquity for soothing irritated and inflamed skin. Oat baths and oat compresses appear in European folk medical traditions and were historically used for a variety of itching skin conditions. Soaked linseeds or oats can be used as a poultice for painfully inflamed skin, and a cloth bag of oats in the bath is regarded as soothing and anti-inflammatory within herbal traditions.
Scientific Evidence: Colloidal oat has relatively consistent support for short-term itching and moisture support, and is commonly found in dermatology recommendations for symptom relief. Colloidal oatmeal is recognized by the U.S. FDA as a safe and effective skin protectant for topical OTC use. The active constituents are thought to include avenanthramides (polyphenols with anti-inflammatory and antipruritic activity) and beta-glucan (a polysaccharide with moisture-retaining properties).
Evidence strength: Moderate for topical use as a skin protectant and short-term itch relief, with regulatory endorsement in the U.S. The evidence base for oral oat consumption in eczema specifically is limited.
5.9 German Chamomile (Matricaria recutita)
Traditional use: Matricaria flower (German chamomile) is externally used in traditional medicine for skin inflammations and irritations, bacterial skin diseases, nappy rash, cradle cap, eczema, wounds (including infected and poorly healing wounds), abscesses, frostbite, and insect bites. It is used in the form of baths, compresses or rinses, and poultices. Ancient Egyptians utilized chamomile for its therapeutic properties.
Scientific Evidence: The essential oil of chamomile and α-bisabolol demonstrated bactericidal and fungicidal activity in vitro (mainly against Gram-positive bacteria, Staphylococcus aureus, Bacillus subtilis, and the fungus Candida albicans). Chamomile's anti-inflammatory activity is attributed primarily to the constituent bisabolol and to the flavonoids apigenin and quercetin. Calendula and chamomile have mixed results in clinical trials; some trials report mild benefit for comfort while others show little difference versus placebo. These well-known medicinal plants, including chamomile, witch hazel, and marigold, have achieved only a low level of evidence for their efficacy because only a few high-quality clinical studies have been performed.
Rare cases of contact allergy to chamomile have been reported.
Evidence strength: Low to preliminary. In vitro and animal data are supportive. Clinical evidence from high-quality controlled trials in eczema specifically is sparse.
5.10 Calendula (Calendula officinalis)
Traditional use: Calendula officinalis (marigold) is native to the Mediterranean countries and has characteristic yellow-orange flower heads. Active ingredients of the calendula flower include triterpene saponins (oleanolic acid glycosides), triterpene alcohols (α-, β-amyrins, faradiol), and flavonoids (quercetin and isorhamnetin). Calendula flower is used in traditional medicine as compresses for poorly healing wounds, bruises, rashes, boils, and dermatitis. Application in children under 6 years of age is generally not recommended.
Scientific Evidence: Calendula and chamomile have mixed results; some trials report mild benefit for comfort while others show little difference versus placebo. In vitro studies suggest anti-inflammatory effects related to the flavonoid and triterpene content. High-quality human RCTs in atopic eczema specifically are limited in number and size.
Evidence strength: Low. Traditional use is well documented; controlled clinical trial evidence in AD specifically remains sparse.
5.11 Licorice Root (Glycyrrhiza glabra / Glycyrrhiza uralensis)
Traditional use: The Greeks employed licorice root for its soothing properties. The preservation of herbal knowledge through texts such as the "Chinese Materia Medica" has contributed to its documented therapeutic use. Licorice root preparations have been used topically across multiple traditional systems for inflammatory skin conditions.
Scientific Evidence: Licorice-derived compounds, particularly glycyrrhizinic acid and licochalcone A, have been studied in controlled trials. In a placebo-controlled study with 26 adults, a cream with licochalcone A as an anti-inflammatory ingredient showed anti-inflammatory effects superior to placebo. A herbal composition containing glycyrrhizinic acid (0.6%) and licorice extract (0.1% Glycyrrhiza uralensis root extract) as main active ingredients displayed anti-inflammatory effects in a placebo-controlled double-blind UV-erythema study, and was found to be as effective as 1% hydrocortisone acetate. The licorice-based product also reduced the severity score in 10 patients with AD treated twice daily over 2 weeks in a non-interventional pilot study. Several clinical trials demonstrated the anti-inflammatory activity of liquorice root to be effective in the topical treatment of atopic eczema.
Evidence strength: Preliminary to low, primarily from small controlled trials. The data support a plausible anti-inflammatory mechanism and provide tentative clinical support for topical preparations, but large, well-powered RCTs are lacking.
5.12 Witch Hazel (Hamamelis virginiana)
Traditional use: Hamamelis virginiana (witch hazel) is a high shrub, or small tree, native to North America. Its bark and leaf preparations have been used by indigenous North American peoples and later adopted in European dermatological practice. Tannins from witch hazel have been empirically used in dermatology, and several plant compounds remain in topical treatments — including tannins from oak bark, black tea, or hamamelis bark for oozing eczema.
Scientific Evidence: Witch hazel is astringent and antimicrobial, and has demonstrated clinical efficacy in treating atopic eczema. Witch hazel ointment has been identified as an effective and safe treatment for eczema in children. These findings are supported by small clinical studies rather than large-scale RCTs. The tannin content of witch hazel is regarded as the key bioactive component responsible for astringent and anti-inflammatory properties.
Evidence strength: Low to preliminary clinical evidence; well-established traditional and ethnobotanical use, with some supporting small trial data.
5.13 St John's Wort (Hypericum perforatum)
Traditional use: Topical preparations of Hypericum perforatum have been used in European herbal medicine for wound healing and inflammatory skin conditions.
Scientific Evidence: St John's Wort cream has been shown to improve atopic eczema in a clinical trial. The evidence is based on a limited number of small controlled studies. Hypericin and hyperforin are regarded as the principal bioactive compounds with anti-inflammatory properties.
Evidence strength: Preliminary. A small number of clinical trials demonstrate a topical benefit signal, but the evidence base is insufficient to draw definitive conclusions.
5.14 Traditional Chinese Herbal Medicine (Zemaphyte and Related Formulas)
Traditional use: Chinese medicine for eczema may include creams, lotions, pills, teas, acupuncture, and acupressure to calm down the overactive immune system that causes eczema flares. Some practitioners using Chinese medicine have reported success treating patients whose eczema had not responded to standard Western medicine.
Scientific Evidence: A 2023 systematic review (18 studies, 881 patients) concluded that overall, there is weak evidence to support any one nutritional supplement intervention for the alleviation of AD symptoms, though multiple trials showed promise for supplements such as Zemaphyte and other herbal compounds. Zemaphyte is a specific standardized Chinese herbal formula whose small-scale RCTs showed benefit in pediatric and adult AD; however, concerns about hepatotoxicity with certain herbal preparations have been raised in the literature, and the original product was withdrawn from the UK market.
Evidence strength: Preliminary for specific standardized formulations. The heterogeneity of Chinese herbal medicine preparations, combined with limited high-quality trial data, means that generalizations are not supportable.
6. Dietary and Lifestyle Factors
6.1 Food Allergies and Elimination Diets
Immune system dysregulation, particularly an overactive response to environmental allergens, also contributes to eczema. Common food allergens including cow's milk, eggs, peanuts, tree nuts, wheat, soy, and fish are identified triggers in a subset of patients with AD, particularly children. However, true IgE-mediated food allergy as a driver of AD must be distinguished from coincidental sensitization. Unguided broad food elimination diets risk nutritional inadequacy, particularly in children, and are not supported by evidence as a general strategy.
Both the European Academy of Allergy and Clinical Immunology and the American Academy of Pediatrics advise a normal diet without restriction for allergenic foods for mothers who are pregnant or breastfeeding.
6.2 Mediterranean Diet
The Mediterranean dietary pattern — characterized by high consumption of vegetables, fruits, legumes, nuts, and fish — has been widely studied in allergic disease. However, the vast majority of studies showed no significant effect of the Mediterranean diet on preventing atopic eczema, rhinitis, or atopy. A 2017 PMC review noted that while adherence to the Mediterranean diet by children appeared to have a protective effect on asthma and wheezing symptoms, adherence to the Mediterranean diet by children seems to have a protective effect on asthma/wheezing symptoms after adjustment for confounders, but by contrast, the vast majority of the studies showed no significant effect of the Mediterranean diet on preventing atopic eczema, rhinitis, or atopy.
6.3 Breastfeeding
The relationship between breastfeeding and eczema risk is contested in the literature. The view that breastfeeding reduces the risk of atopic disease in the child is widely accepted and promoted; however, published research shows conflicting results on the effect of breastfeeding on atopic diseases. A large cohort study (5,676 children) found that breastfeeding was not associated with current eczema. Compared with children who had never been breastfed, the adjusted odds ratios for current eczema at any age were 1.02 for breastfeeding 0–3 months, 0.97 for 4–6 months, and 0.98 for more than 6 months. A separate birth cohort study found that each additional month of breastfeeding was associated with increased eczema odds in a high-risk population, underscoring the complexity of this relationship and the importance of confounding by parental atopy.
6.4 Gut Microbiome Modulation Through Diet
The use of prebiotics, probiotics, or synbiotics has been investigated for their potential benefits on the host in order to prevent and/or treat food allergies. The consumption of prebiotics has been suggested to provide more favorable microbial colonization patterns and potentially allow for the development of tolerance and the prevention of allergy. There are limited studies investigating the role of prebiotic supplementation on food allergy prevention specifically.
Dietary diversity, fiber intake, and fermented food consumption are proposed as relevant lifestyle factors for supporting a diverse gut microbiome. The delayed colonization of Bifidobacteria, limited microbial diversity, and early enrichment of Escherichia coli and Klebsiella in the gastrointestinal tract of infants with AD during the early postnatal period may serve as a composite predictive biomarker for AD but would require further validation in other cohorts.
6.5 Psychological Stress
Psychological stress is a significant environmental factor influencing the course of AD, a chronic inflammatory skin condition marked by pruritus and recurrent eczematous lesions. Stress is thought to modulate immune responses through neuroendocrine pathways. The skin and the nervous system share a common developmental origin (neuroectoderm), and there are direct bidirectional connections between the central nervous system and skin immune cells, a field termed psychoneuroimmunology. The relationship between stress and AD flares is clinically observed and supported by prospective cohort data, though the mechanistic details in humans are still being elaborated.
6.6 Sleep and Exercise
AD has significant bidirectional associations with sleep disturbance, driven primarily by nocturnal pruritus. Evidence regarding the association between lifestyle factors and eczema is a recognized area of inquiry, with factors including smoking, alcohol consumption, stress, physical activity, body mass index, diet, and sleep studied in relation to eczema prevalence, incidence, subtype, severity, and prognosis. Exercise may trigger flares through sweating and skin microtrauma in some individuals, while regular moderate physical activity may benefit immune regulation more broadly. The evidence is primarily observational.
6.7 Skin-Focused Lifestyle Factors
Beyond nutrition, several lifestyle modifications are widely discussed in clinical dermatology literature in relation to eczema management. These include: avoidance of harsh soaps, detergents, and synthetic fragrances that disrupt skin barrier integrity; use of fragrance-free emollients applied to damp skin; temperature regulation (overheating and sweating are documented triggers); and management of environmental allergens such as house dust mites, animal dander, and mold. Defective permeability barrier function enables enhanced penetration of environmental allergens into the skin and initiates immunological reactions and inflammation, confirming that barrier dysfunction is crucially involved in the pathogenesis of AD.
7. Summary of Evidence Quality
- Vitamin D: Multiple RCTs and meta-analyses; moderate evidence of benefit particularly in vitamin D-deficient individuals. Context-dependent.
- Probiotics (select strains): Moderate evidence for prevention in high-risk infants; mixed and strain-dependent for AD treatment. Most consistent data for L. rhamnosus GG.
- Colloidal oatmeal (topical): Moderate evidence for short-term itch relief and skin protection; FDA-recognized skin protectant.
- Omega-3 fatty acids: Mixed; individual trials show benefit but pooled Cochrane review findings are insufficient for a recommendation.
- Vitamin E and B12: Preliminary; based on small RCTs with wide confidence intervals.
- Zinc: Insufficient evidence for routine supplementation; no clinically meaningful benefit identified in the largest systematic review.
- Evening primrose oil / borage oil (oral GLA): Negative evidence from Cochrane review (27 RCTs, 1,596 participants); not recommended.
- Licorice root (topical): Preliminary; small controlled trials show anti-inflammatory signal comparable to low-potency corticosteroids in limited study populations.
- Chamomile, calendula, witch hazel, St John's Wort: Low clinical evidence; strong traditional use and in vitro support; sparse high-quality RCT data.
- Chinese herbal medicine (standardized formulas): Preliminary benefit signal from small RCTs; safety concerns with some preparations require consideration.
- Mediterranean diet: No consistent evidence of protection against eczema specifically, despite benefits documented for asthma in some cohorts.
References
- StatPearls – Eczema (NCBI Bookshelf / NIH)
- NIAMS – Atopic Dermatitis: Symptoms & Causes (NIH)
- Atopic Dermatitis: A Review of Diagnosis and Treatment (PMC, 2024)
- StatPearls – Atopic Dermatitis (NCBI Bookshelf)
- What is "eczema"? – PMC 2025
- The etiopathogenesis of atopic dermatitis: barrier disruption, immunological derangement, and pruritus (PMC)
- Atopic Dermatitis: A Disease of Altered Skin Barrier and Immune Dysregulation (PMC)
- The immunological and structural epidermal barrier dysfunction and skin microbiome in atopic dermatitis – an update (PMC)
- Atopic dermatitis: immune deviation, barrier dysfunction, IgE autoreactivity and new therapies (ScienceDirect)
- The role of the skin microbiome in atopic dermatitis (PMC / NIH)
- The microbiome in patients with atopic dermatitis (PMC / NIH)
- Understanding the role of Staphylococcus aureus in atopic dermatitis (PMC)
- Skin and gut microbiome in atopic dermatitis (PMC / NIH)
- Gut Microbiota and Food Allergy: A Review of Mechanisms and Microbiota-Targeted Interventions (PMC)
- Assessment of the Effectiveness of Vitamin Supplement in Treating Eczema: A Systematic Review and Meta-Analysis (PMC)
- Clinical Efficacy of Nutritional Supplements in Atopic Dermatitis: Systematic Review (JMIR Dermatology, 2023)
- Dietary supplements for established atopic eczema – Cochrane review (PMC / NIH)
- Bath-Hextall et al. – Dietary supplements for established atopic eczema (PubMed, Cochrane, 2012)
- Bamford et al. – Oral evening primrose oil and borage oil for eczema (Cochrane, 2013)
- Bamford et al. – Oral evening primrose oil and borage oil for eczema (PubMed)
- Oral evening primrose oil and borage oil for eczema (PMC / Cochrane)
- NCCIH – Evening Primrose Oil: Usefulness and Safety
- Medicinal plants used in treatment of inflammatory skin diseases (PMC)
- New Herbal Biomedicines for the Topical Treatment of Dermatological Disorders (PMC)
- What Are the Effects of a Mediterranean Diet on Allergies and Asthma in Children? (PMC)
- Association between breastfeeding and eczema during childhood and adolescence: A cohort study (PMC)
- Lifestyle factors and hand eczema: A systematic review and meta-analysis of observational studies (PMC)
- Examine.com – Omega-3s, omega-6s, and vitamin D for pediatric eczema (RCT Summary)
Go back