There is no single “best brand” for everyone; the right decision is driven by quality criteria, not the logo. Key markers to look for include: (1) clear labeling of elemental magnesium per serving, (2) transparent identification of the exact form (glycinate/bisglycinate and whether it is a blend), (3) minimal unnecessary additives, and (4) credible manufacturing standards with ideally third-party testing for purity and contaminants. Elemental magnesium per capsule/tablet also matters because it makes dosing more predictable. Some products are “buffered,” meaning they may contain mixed magnesium forms, which can change tolerability or effects. Choose based on your goal (sleep, cramps, general support), tolerance, and budget. If you have kidney disease or take multiple medications, selecting supplements with clinical guidance is the safest approach.