Best Vitamin D for Immunity
Evidence-based ranking of vitamin d options for immunity. Updated February 2026.
Vitamin D3
Score: 9.3/10. Foundation for immune health, especially in winter
Complete Rankings
Foundation for immune health, especially in winter
PROS
- Critical for immune function
- Most people deficient
- Very safe
CONS
- • Needs testing for optimal dose
- • Takes time to raise levels
Fighting colds, supporting immune cell function
PROS
- Shortens cold duration
- Critical for immune cells
- Cheap
CONS
- • Can cause nausea
- • Depletes copper long-term
Daily immune support, especially during stress
PROS
- Antioxidant
- Supports white blood cells
- Very safe
CONS
- • GI issues at high doses
- • Modest effect size
Flu season, acute illness support
PROS
- Reduces flu duration
- Natural antiviral
- Pleasant taste
CONS
- • Must be cooked/processed
- • Limited research outside flu
Quick Comparison
| Supplement | Score | Dose | Onset | Cost |
|---|---|---|---|---|
| Vitamin D3 | 9.3 | 2000-5000 IU daily | 4-8 weeks to optimize levels | $ |
| Zinc | 8.9 | 15-30mg daily (up to 75mg when sick) | Days when sick, weeks for prevention | $ |
| Vitamin C | 8.5 | 500-1000mg daily | Ongoing support | $ |
| Elderberry | 8 | 150-300mg extract daily | Days when sick | $$ |
Common Questions
Based on clinical evidence, Vitamin D3 ranks as the top choice for immunity. It scores 9.3/10 due to Critical for immune function and Most people deficient. Foundation for immune health, especially in winter.
Related Guides
Get Personalized Recommendations
Tell us your goals and get a custom supplement plan
No spam. Unsubscribe anytime. We respect your inbox.
How We Rank
Our rankings are based on: clinical evidence quality (40%), effect size (30%), safety profile (20%), and value (10%). We analyze meta-analyses and RCTs from PubMed, Cochrane, and peer-reviewed journals.
Disclaimer: This is educational content, not medical advice. Consult a healthcare provider before starting any supplement regimen.