Nature's Bounty
Adequate vitamin D3 supplement with standard potency, but lacks third-party testing verification and contains several synthetic additives.
Evaluated Feb 15, 2026
·AI-evaluatedThorne
NSF certified with third-party testing and minimal, clean ingredients without artificial additives.
Nordic Naturals
Third-party tested with organic olive oil base and no artificial colors or preservatives.
Garden of Life
Whole food-based formula with organic ingredients and third-party testing verification.
Contains synthetic additives and artificial colors but uses cholecalciferol (D3)
No clear third-party testing verification or COA availability
Uses bioavailable D3 form in oil-based softgel for better absorption
Clear potency labeling but limited information about sourcing and testing