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Head-to-head evidence comparison — which supplement is right for you?
PEA vs Vitamin D3: Vitamin D3 has the stronger overall evidence (7.5 vs 7.5/10); they're alternatives for pms relief — the best pick depends on your goals. Take the 60-second quiz for a pick tailored to your goals.
Vitamin D3 wins 1 of 3 categories. Both are solid choices — the best pick depends on your specific goals.
Verdict
Too few graded studies
1 of 1 studies with measurable effects showed benefit.
Top outcomes
Verdict
Probably helps
7 of 14 studies with measurable effects showed benefit.
Top outcomes
Shared outcomes (1)
Outcomes where both PEA and Vitamin D3 have evidence — compare verdict strength side-by-side.
600-1200mg
Two divided doses a day, as in the knee osteoarthritis and burning mouth trials, Or 400 mg three times a day (1,200 mg a day)
Micronised or ultramicronised PEA
2000-4000 IU daily
Morning with breakfast
D3 (cholecalciferol) softgel or liquid
and 1 more not shown
2-8 weeks
4-8 weeks
Ongoing
4-8 weeks
4-8 weeks
2-4 weeks
4-8 weeks
Extended Treatment with Micron-Size Oral Palmitoylethanolamide (PEA) in Chronic Pain: A Systematic Review and Meta-Analysis
Nutrients (2024) · Meta analysis · n=742
These two obtained scores corresponded to a 35.1% pain intensity reduction within the first month, followed by a further 35.4% during the second month.
Palmitoylethanolamide in the Treatment of Chronic Pain: A Systematic Review and Meta-Analysis of Double-Blind Randomized Controlled Trials
Nutrients (2023) · Meta analysis · n=774
PEA was found to reduce pain scores relative to comparators in a pooled estimate, with a standard mean difference of 1.68 (95% CI 1.05 to 2.31, p = 0.00001).
Navigating agitation in neurodevelopmental disorders: A comparative study of pharmacotherapies via network meta-analysis in children and adults with autism spectrum disorder or intellectual disabilities
Journal of psychopharmacology (Oxford, England) (2025) · Meta analysis · n=2503
Importantly, these treatments were generally well-tolerated, with no significant increase in all-cause dropouts compared to placebo, highlighting their suitability for clinical use in managing agitation in individuals with ASD or ID.
Vitamin D supplementation vs. placebo and incident type 2 diabetes in an ancillary study of the randomized Vitamin D and Omega-3 Trial
Nature communications (2025) · Rct · n=22220
Ancillary analysis of VITAL: 22,220 adults without T2D randomized to vitamin D3 2000 IU/day or placebo, with a meta-analysis of 3 additional trials.
Vitamin D Supplementation for Patients with Dysmenorrhoea: A Meta-Analysis with Trial Sequential Analysis of Randomised Controlled Trials
Nutrients (2024) · Meta analysis · n=687
TSA revealed that the current RCTs provide sufficient information.
Vitamin D and respiratory tract infections
BMJ (2017) · Meta analysis · n=11321
25 RCTs, 11 321 participants aged 0 to 95 years. Vitamin D reduced acute respiratory tract infection overall (adjusted OR 0.88, 95% CI 0.81 to 0.96).
Both points come from a meta-analysis of double-blind cholecalciferol trials in people aged 60 and over (PMID 15886381). Trials at 700 to 800 IU a day cut hip fracture risk by 26% (RR 0.74) and non-vertebral fractures by 23%, plotted at 800 IU. Trials at 400 IU a day showed no benefit (hip fracture RR 1.15), and the WHI trial of 400 IU with 1,000 mg calcium did not significantly reduce hip fracture (PMID 16481635). Most of these trials also gave calcium, and the Cochrane review found vitamin D alone unlikely to prevent fractures while vitamin D with calcium gave a small reduction (PMID 24729336). Doses above 800 IU were not compared, so no optimal dose or ceiling is set.
AI-estimated from published studies. Interpret as directional guidance.
Vitamin D3 has a higher evidence score (7.5/10 vs 7.5/10) and wins in 1 of 3 categories.
For pms relief, Vitamin D3 has a higher relevance score (78 vs 65).
No documented interaction was found in the data searched. This does not establish that this exact combination is safe.
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The right pick depends on your goals. Answer a few quick questions for a personalised recommendation — or dig into the full evidence on each.