Nutritional Supplements for Eczema Relief - Review Analysis

review PMID: 38019566

Quick Summary: Researchers reviewed studies on supplements for eczema (atopic dermatitis). They found some evidence that vitamin D might help, especially if you're low on it. Probiotics showed mixed results, and other supplements like omega-3s and zinc didn't seem to make a big difference. This review did not include apple cider vinegar.

What The Research Found

This review looked at many studies on different supplements for eczema. The strongest evidence was for vitamin D, which seemed to help people with low vitamin D levels. Some probiotics showed a small benefit in kids. Other supplements like omega-3s and zinc didn't show much improvement. Important note: This review did not study apple cider vinegar.

Study Details

Who was studied: People with eczema of all ages, from babies to adults.

How long: The studies lasted from a few weeks to several months.

What they took: The studies looked at vitamin D, probiotics, omega-3 fatty acids, zinc, and other supplements. The dosages varied.

What This Means For You

If you have eczema, this review suggests:

Vitamin D: If you're low on vitamin D, getting more might help. Talk to your doctor about getting your levels checked.

Probiotics: Some probiotics might help, especially in kids, but the results are mixed.

Other Supplements: Omega-3s and zinc didn't show much benefit in these studies.

Apple Cider Vinegar: This review did not study apple cider vinegar, so we can't say anything about its effectiveness for eczema based on this research.

Study Limitations

The studies used different supplements and doses, making it hard to compare results.

Some studies weren't very well-designed.

The review didn't look at the long-term safety of the supplements.

No studies on apple cider vinegar were included.

Key Findings

This systematic review analyzed 45 clinical trials evaluating nutritional supplements for atopic dermatitis (AD). No significant evidence supported apple cider vinegar (ACV) for AD management. The review found moderate evidence for vitamin D supplementation improving SCORAD (Severity Scoring of Atopic Dermatitis) index in deficient patients (mean difference -6.2, 95% CI -10.1 to -2.3; p=0.002). Probiotics showed inconsistent results, with only specific strains (e.g., Lactobacillus rhamnosus GG) demonstrating modest efficacy in pediatric AD (p<0.05 in 3 of 12 trials). Omega-3 fatty acids and zinc showed no clinically meaningful benefits. 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.

Study Design

This was a systematic review (not a primary clinical trial) adhering to PRISMA guidelines. Researchers screened 1,287 articles from PubMed, EMBASE, and Cochrane Library (inception to October 2023), ultimately including 45 randomized controlled trials (RCTs) involving 4,127 AD patients across 18 countries. Studies evaluated diverse supplements including vitamins (D, E, B12), probiotics, omega-3, zinc, and others. No studies on apple cider vinegar met inclusion criteria. Patient demographics varied widely: 58% pediatric participants (ages 6 months–18 years), 42% adults, with moderate-to-severe AD defined by SCORAD >40 in 67% of trials.

Dosage & Administration

Dosage details were extracted from included primary studies but varied significantly across supplements. Vitamin D trials used 1,000–4,000 IU/day orally for 8–24 weeks. Probiotic regimens ranged from 10⁹–10¹⁰ CFU/day of single/multi-strain formulations for 4–16 weeks. Omega-3 doses spanned 0.5–5.7 g/day. Apple cider vinegar was not evaluated in any included study, so no dosage data exists within this review's scope.

Results & Efficacy

Vitamin D demonstrated the strongest evidence: 7 of 11 trials showed significant SCORAD improvement in deficient patients (p<0.05), with pooled analysis confirming efficacy (MD -6.2, 95% CI -10.1 to -2.3; p=0.002). Probiotics showed statistically significant but clinically marginal effects in only pediatric subgroups (mean SCORAD reduction 3.1–5.4; p<0.05 in positive trials). Omega-3 and zinc showed no significant improvements in primary endpoints (p>0.05 across 9 and 5 trials respectively). Heterogeneity was high (I²>75%) for most meta-analyses, limiting definitive conclusions.

Limitations

Major limitations included high heterogeneity in supplement formulations, dosages, and AD severity across studies. 62% of included trials had high risk of bias (primarily due to inadequate blinding). Publication bias was evident in funnel plots for vitamin D analysis. The review excluded non-English studies and did not assess long-term safety. Crucially, apple cider vinegar was absent from all analyzed literature, reflecting a research gap rather than evidence of inefficacy.

Clinical Relevance

Supplement users should not expect ACV to treat eczema based on current evidence. Vitamin D supplementation may benefit AD patients with documented deficiency, but self-dosing without testing is not supported. Probiotic effects are strain-specific and modest at best. The review underscores that most supplements lack robust evidence for AD management, and patients should prioritize evidence-based therapies (e.g., topical calcineurin inhibitors) over unproven supplements. Clinicians should screen for vitamin D deficiency in refractory AD cases before considering supplementation.