Comparison
Compare evidence before buying.
Side-by-side scores from cited research. Narrow by category, then pick the exact products you want to weigh against each other.
All productsSupplements (20)Skincare (17)Fitness (16)Sleep (15)Heart Health (10)Cognitive Enhancement (8)Nutrition (8)Recovery (8)Bone & Joint Health (5)Mental Health (5)Metabolic Health (5)Immune Health (4)Biomarker Testing (3)Wearables (3)Gut Health (2)Hormonal Health (2)Oral Health (2)Respiratory Health (2)Vision Health (2)Air Quality (1)Blood Testing (1)Cold Therapy (1)Ergonomics (1)Hair Health (1)Microbiome Testing (1)Red Light Therapy (1)Saunas (1)Water Quality (1)Women's Health (1)
Choose products to compare3/4 selected
| Product |  Vitamin D3 5000 IU + K2 (MK-7) 100mcg Sports Research · Immune Health |  Axwell Vitamin C Serum for Face – 10% Vitamin C + Niacinamide – Daily Glow & Radiance Facial Serum with Hyaluronic Acid – Hydrating Skin Care for Even Tone (1 fl oz) AXWELL · Skincare |  Optimum Nutrition Serious Mass, Weight Gainer Protein Powder, Mass Gainer, Vitamin C and Zinc for Immune Support, Creatine, Chocolate, 6 Pound (Packaging May Vary) Optimum Nutrition · Supplements |
|---|---|---|---|
| Evidence Score | 77Strong | 66Good | 53Emerging |
| Safety Score | 59Good | 66Good | 66Good |
| Effectiveness | 77Strong | 60Good | 43Emerging |
| Research Confidence | 68Good | 68Good | 73Strong |
| Product Fit | 74Strong | 53Emerging | 39Limited |
| Evidence directness | Ingredient-level evidence | Direct product evidence | Direct product evidence |
| Papers indexed | 3 | 5 | 5 |
| Top verified claim | Delivers a supplemental dose sufficient to raise low serum vitamin D over weeks. | Improves skin hydration and moisture retention | Supports maintenance of muscle mass during aging |
| Price | $21.95 | $27.99 | $44.00 |
| Open evidence page | Open evidence page | Open evidence page |
Scores reflect cited research, not medical advice. Highlighted cells mark the strongest score per row among the products shown.