We use essential cookies (authentication, your saved goals/stack) by default. With your permission we’ll also enable privacy-respecting analytics (Vercel Web Analytics, anonymous load-time metrics) and error-replay diagnostics (Sentry — DOM snapshots only when an error fires) so we can fix bugs faster. Learn more about cookies
Head-to-head evidence comparison — which supplement is right for you?
Elderberry vs Vitamin D3: Vitamin D3 has the stronger overall evidence (7.5 vs 6/10); they're alternatives for support immune system — the best pick depends on your goals. Take the 60-second quiz for a pick tailored to your goals.
Vitamin D3 wins 2 of 3 categories. Both are solid choices — the best pick depends on your specific goals.
Verdict
Likely helps
4 of 4 studies with measurable effects showed benefit.
Top outcomes
Verdict
Probably helps
13 of 23 studies with measurable effects showed benefit.
Top outcomes
600-900mg extract daily during illness
At first sign of symptoms, Multiple times daily during illness
Standardized extract (syrup or capsules)
2000-4000 IU daily
Morning with breakfast
D3 (cholecalciferol) softgel or liquid
and 1 more not shown
When taken at symptom onset
During illness
4-8 weeks
4-8 weeks
2-4 weeks
4-8 weeks
Genus Sambucus: Exploring Its Potential as a Functional Food Ingredient with Neuroprotective Properties Mediated by Antioxidant and Anti-Inflammatory Mechanisms
International journal of molecular sciences (2024) · Review
In vivo studies using animal models of neurodegenerative diseases, such as Alzheimer's and Parkinson's, have shown that Sambucus compounds can improve cognitive function, motor performance, and neuronal survival while attenuating neuroinflammation and oxidative damage.
Label compliance for ingredient verification: regulations, approaches, and trends for testing botanical products marketed for "immune health" in the United States
Critical reviews in food science and nutrition (2024) · Review
Meanwhile, consumers showed increased attention to dietary supplement ingredient labels, especially concerning authenticity and ingredient claims.
Select Dietary Supplement Ingredients for Preserving and Protecting the Immune System in Healthy Individuals: A Systematic Review
Nutrients (2022) · Systematic review
Immune health products represent approximately 10% of all US dietary supplement sales.
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) · Meta analysis · n=5205
Mean body mass index (BMI) was 27.5 kg/m2 (SD = 5.3), with 51% female and 17% Black race/ethnicity.
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
12% reduction in respiratory infections overall
Based on limited studies showing 2-4 day reduction in illness duration. Evidence primarily from small RCTs with methodological limitations. Effectiveness may vary significantly between individuals.
Meta-analysis showed 12% overall reduction in respiratory infections, with greater benefits in severely deficient individuals. Daily dosing more effective than bolus. Conservative estimate assumes most users not severely deficient.
AI-estimated from published studies. Interpret as directional guidance.
Vitamin D3 has a higher evidence score (7.5/10 vs 6/10) and wins in 2 of 3 categories.
For support immune system, Vitamin D3 has a higher relevance score (92 vs 80).
No known interactions between Elderberry and Vitamin D3 have been documented in our database. However, always consult a healthcare provider before combining supplements.
Zinc timing, vitamin D, the real vitamin C effect — and the elderberry caution.
The honest tier list — proven staples vs situational vs mostly marketing. The hub the other guides feed into.
On Ozempic/Wegovy/Mounjaro? What actually helps — muscle preservation, GI relief, nutrient gaps (no upsell).
Tired? Why most "energy" pills only work if they fix a deficit — and how to find yours first.
The right pick depends on your goals. Answer a few quick questions for a personalised recommendation — or dig into the full evidence on each.