Eczema, medically known as atopic dermatitis, affects roughly 1 in 10 adults and up to 1 in 5 children at some point, and it rarely shows up alone — itchy, dry, inflamed skin is often accompanied by a weakened skin barrier that lets moisture out and irritants in. While prescription creams and dermatologist care remain the backbone of treatment, a growing body of nutrition research points to specific nutrients and habits that can meaningfully reduce flare frequency and severity when used alongside standard care. Here is what the evidence actually supports, and what is still unproven.
Quick Facts
- It's a barrier problem first: most atopic dermatitis involves a genetically weakened skin barrier (often linked to filaggrin gene variants) that lets water escape and allergens in.
- Daily moisturizing works: a large 2025 randomized trial found that full-body emollient use from early infancy meaningfully lowered the risk of developing eczema.
- Vitamin D has real trial support: supplementation has been shown in multiple controlled trials to measurably reduce eczema severity scores.
- Not every "natural" remedy holds up: evening primrose oil, borage oil, and oral zinc have each been tested in controlled trials and shown no meaningful benefit.
- Omega-3 fats show modest, real promise: several small-to-moderate trials report reduced severity scores with fish-oil-derived DHA/EPA, though results are not universal.
Understanding the Skin Barrier
Healthy skin depends on a tightly packed outer layer of cells held together by lipids and structural proteins — often compared to bricks and mortar. In atopic dermatitis, this "mortar" is frequently compromised, partly due to variants in the gene for filaggrin, a protein essential for keratinocyte structure and for producing the skin's natural moisturizing factors. A weaker barrier means faster water loss, drier skin, and easier entry for irritants and allergens, which helps explain why atopic skin is so reactive and itch-prone even between visible flares.
Where Nutrition Fits In
Because eczema involves both a structural skin problem and an overactive immune response, nutrients that support barrier lipids or calm inflammatory signaling are the most plausible dietary levers. Omega-3 fatty acids are best studied here, since they are incorporated into cell membranes and can shift the balance of inflammatory signaling molecules. Vitamin D plays a separate role, supporting keratinocyte function and immune regulation in the skin. Zinc is involved in wound healing and skin integrity, though as the evidence section below shows, supplementing it orally has not translated into clear symptom relief.
Triggers Beyond Diet
Nutrition is only one piece. Hot showers, harsh soaps, wool or synthetic fabrics, sweat, low humidity, stress, and airborne allergens (dust mites, pet dander, pollen) are all well-documented flare triggers. Identifying and reducing exposure to a person's specific triggers, alongside any nutritional support, is typically where the biggest day-to-day improvements come from.
What the Evidence Actually Shows
Daily emollient use in infancy can reduce the risk of developing eczema. Evidence level: Well-established. A large, pragmatic randomized trial (the CASCADE trial, published in JAMA Dermatology in 2025) followed 1,247 infants and found that daily full-body moisturizer application starting around 9 weeks of age reduced cumulative eczema incidence by age two, with the strongest effect in infants without a family history of atopic disease.
Vitamin D supplementation can reduce eczema severity scores. Evidence level: Promising. A systematic review and meta-analysis in Nutrients pooling multiple randomized trials found that vitamin D supplementation (roughly 1,600 IU/day for around three months) was associated with a clinically meaningful drop in SCORAD severity scores, and atopic dermatitis patients as a group tend to have lower circulating vitamin D than healthy controls.
Omega-3 (DHA/EPA) supplementation may modestly improve symptoms. Evidence level: Promising. A randomized, double-blind trial published in the British Journal of Dermatology found that 5.4g/day of DHA improved SCORAD scores over eight weeks compared to a control fat, and a 2024 triple-blind placebo-controlled trial in children (Nutrients) reported reduced SCORAD, itch, and topical steroid use after four months of omega-3/6 supplementation. Not every trial has shown a benefit, so this is considered promising rather than settled.
Oral probiotics may help modestly, particularly for prevention. Evidence level: Promising. A 2018 Cochrane review of probiotics for treating existing eczema found only limited, inconsistent benefit for established disease, but separate meta-analyses suggest probiotic supplementation during pregnancy and early infancy is associated with a reduced risk of a child later developing eczema.
Evening primrose oil, borage oil, and oral zinc do not show clear benefit. Evidence level: Not supported by current evidence. A Cochrane review covering 27 trials and nearly 1,600 participants found no meaningful improvement in eczema symptoms from oral evening primrose or borage oil. Similarly, a controlled trial of high-dose oral zinc sulfate in children with atopic eczema (European Journal of Clinical Nutrition) found no significant improvement in severity, itch, or sleep disturbance compared to placebo.
Practical Steps That Match the Evidence
Rebuild the Barrier First
Apply a fragrance-free emollient at least once daily, ideally within a few minutes of bathing while skin is still damp, to lock in moisture. Choose thick creams or ointments over light lotions, and keep showers short and lukewarm rather than hot, since heat strips protective skin lipids.
Consider Vitamin D Status
If sun exposure is limited or a blood test shows low levels, a vitamin D supplement in the range studied in trials (around 1,000–2,000 IU/day) is a reasonable, low-risk addition to discuss with a clinician, particularly during winter months.
Add Omega-3s Through Food or Supplements
Fatty fish two to three times per week, or a fish oil supplement providing DHA and EPA, mirrors the doses used in trials showing modest improvement. Effects, when present, typically take several weeks to become noticeable.
Track and Reduce Personal Triggers
Keep a simple log of flares alongside soaps, fabrics, foods, stress levels, and weather to spot patterns. Switching to fragrance-free laundry detergent and skincare products is one of the highest-yield, lowest-effort changes most people can make.
Safety and Who Should Be Cautious
Nutritional support is meant to complement, not replace, dermatologist-directed treatment, especially for moderate-to-severe eczema or when skin shows signs of infection (increased pain, spreading redness, warmth, or pus). High-dose fish oil can have a mild blood-thinning effect and should be used cautiously alongside anticoagulant medication. Vitamin D supplementation above 4,000 IU/day should generally be guided by blood testing, since excess intake can raise calcium levels over time. Zinc supplementation at high doses can interfere with copper absorption and cause gastrointestinal upset, which is one more reason the evidence does not currently support routine use for eczema.
ⓘ Infants, pregnant or breastfeeding individuals, and anyone with widespread, infected, or rapidly worsening eczema should be evaluated by a physician or dermatologist before starting any new supplement regimen.
Frequently Asked Questions
Can diet alone cure eczema?
No. Diet and supplements can meaningfully reduce severity and flare frequency for some people, but eczema is a chronic condition driven by genetics, immune function, and skin barrier biology, so it typically requires an ongoing management plan rather than a single fix.
How long before omega-3 or vitamin D supplementation shows a difference?
Most trials measuring improvement used supplementation periods of two to three months before reassessing severity scores, so it's reasonable to give either approach at least that long before judging its effect.
Are food allergies the main cause of eczema?
Not usually. While some children with moderate-to-severe eczema also have food allergies, most eczema is not caused by a specific food, and unsupervised elimination diets can lead to unnecessary nutritional gaps without improving skin symptoms.
Is it worth trying evening primrose oil if other things haven't worked?
Based on the largest and most rigorous trials to date, evening primrose and borage oil are unlikely to help, and continuing to invest in them instead of barrier repair or evidence-supported nutrients is probably not the best use of time or money.
Does moisturizing really prevent eczema, or just soothe it once it starts?
Both. Emollients soothe active flares, but the 2025 CASCADE trial specifically found that starting daily moisturizing in early infancy, before any eczema appeared, lowered the chance that eczema developed in the first place.
Scientific References
- Koch C, Dölle S, Metzger M, et al. "Docosahexaenoic acid (DHA) supplementation in atopic eczema: a randomized, double-blind, controlled trial." British Journal of Dermatology. 2008;158(4):786-792.
- Niseteo T, Hojsak I, Ožanić Bulić S, Pustišek N. "Effect of Omega-3 Polyunsaturated Fatty Acid Supplementation on Clinical Outcome of Atopic Dermatitis in Children." Nutrients. 2024;16(17):2829.
- Hattangdi-Haridas SR, Lanham-New SA, Wong WHS, Ho MHK, Darling AL. "Vitamin D Deficiency and Effects of Vitamin D Supplementation on Disease Severity in Patients with Atopic Dermatitis: A Systematic Review and Meta-Analysis in Adults and Children." Nutrients. 2019;11(8):1854.
- Makrgeorgou A, Leonardi-Bee J, Bath-Hextall FJ, Murrell DF, Tang MLK, Roberts A, Boyle RJ. "Probiotics for treating eczema." Cochrane Database of Systematic Reviews. 2018;(11):CD006135.
- Bamford JTM, Ray S, Musekiwa A, van Gool C, Humphreys R, Ernst E. "Oral evening primrose oil and borage oil for eczema." Cochrane Database of Systematic Reviews. 2013;(4):CD004416.
- Ewing CI, Gibbs ACC, Ashcroft C, David TJ. "Failure of oral zinc supplementation in atopic eczema." European Journal of Clinical Nutrition. 1991;45(10):507-510.
- Moosbrugger-Martinz V, Leprince C, Méchin MC, Simon M, Blunder S, Gruber R, Dubrac S. "Revisiting the Roles of Filaggrin in Atopic Dermatitis." International Journal of Molecular Sciences. 2022;23(10):5318.
- Simpson EL, Michaels LC, Ramsey K, et al. "Emollients to Prevent Pediatric Eczema: A Randomized Clinical Trial." JAMA Dermatology. Published online July 23, 2025.
Disclaimer
This article is for educational purposes only and is not intended as medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider or dermatologist before starting any new supplement, changing your skincare routine, or making changes to the management of a diagnosed skin condition, especially if you are pregnant, breastfeeding, immunocompromised, or managing eczema in an infant or child.
