Memory is shaped more by a “brain-health ecosystem” than by any single supplement: sleep, physical activity, glucose control, B vitamins, omega-3s, stress management, and cardiovascular health are key. Magnesium supports nervous system function, so correcting low intake may indirectly help concentration and overall mental performance. A realistic goal is not “magnesium boosts memory for everyone,” but ensuring adequacy as part of a broader plan. If supplementing, start with a modest dose, choose a well-tolerated form, and consider kidney health and medication interactions. Persistent forgetfulness or cognitive symptoms that affect daily life should be evaluated by a clinician.