Fact check: What are proven treatments and evidence-based therapies for dementia and how do they compare to over-the-counter supplements?

1. What researchers claim about supplements and nutrition — promising signals but disappointing trials

Systematic reviews and expert reviews describe nutritional factors as plausible modifiers of dementia risk, but randomized trials of dietary or single‑nutrient supplements produce largely null results, limited by trial design, heterogeneity, and biomarker shortcomings. One major review urged better trial methods—integrating dietary patterns, genetic stratification, and biomarkers—to detect possible preventive benefits rather than relying on simplistic supplement trials that have repeatedly failed to show cognitive improvement. A protocol for network meta‑analysis aims to rank supplements for mild cognitive impairment or Alzheimer’s disease but reflects ongoing uncertainty and the need for higher‑quality trials. Clinical nutrition guidelines recommend oral nutritional supplements to treat malnutrition, not to reverse cognitive decline, underscoring that nutrition care is essential for general health but not proven as a cognitive therapy ^{[4] [5] [3]}.

2. The pharmacologic toolbox: modest, specific, evidence‑based benefits

High‑quality comparative reviews find cognitive enhancers such as cholinesterase inhibitors (donepezil, galantamine) and memantine provide measurable but modest benefits for symptomatic Alzheimer’s dementia; network meta‑analysis of cognitive enhancers confirms efficacy with an established safety profile to guide use. Effect sizes are not large—clinical gains are modest and balanced against side effects—yet these agents remain the primary evidence‑based pharmacologic options for symptomatic management. For behavioral and psychological symptoms, atypical antipsychotics show small benefits for agitation or psychosis but carry safety concerns; antidepressants such as mirtazapine have failed to show efficacy and may increase risk in some trials. Pharmacologic therapy is targeted and incremental, not curative ^{[1] [2] [6]}.

3. Non‑drug interventions outperform supplements for behavior and quality of life

Recent systematic reviews highlight non‑pharmacologic interventions—music therapy, personalized music, lighting adjustments, and person‑centered digital programs—as consistently effective and safer alternatives for agitation and BPSD (behavioral and psychological symptoms of dementia). Trials show modest but reproducible reductions in agitation without the adverse events seen with many drugs. One 2025 review found drugs had mixed results while structured non‑drug programs delivered benefit with fewer harms, reinforcing guidelines that prioritize non‑drug strategies first for behavioral issues. This evidence places person‑centered environmental and psychosocial care at the center of practical dementia management, with supplements largely absent from these treatment recommendations ^{[6] [2]}.

4. How guidelines treat nutrition versus cognitive claims — prevention versus care

Expert guidance separates nutritional care for preventing malnutrition and dehydration from claims that nutrition or supplements modify dementia trajectories. The ESPEN guideline recommends adequate staffing, appetizing food, and oral nutritional supplements to improve nutritional status but explicitly states these interventions are not proven to correct cognitive impairment or prevent decline. That distinction matters clinically: ensuring hydration and weight stability reduces complications and improves quality of life, but the same interventions are not evidence‑backed dementia therapies. Current guidelines therefore endorse nutrition as essential supportive care, not as a substitute for evidence‑based pharmacologic and psychosocial treatments ^[3].

5. Comparing risk, effect size, and evidence quality: why supplements lag

Across systematic reviews, effect sizes for approved drugs and non‑drug therapies are small but confirmed in multiple trials, while OTC supplements show inconsistent or null results with low overall quality of evidence. Supplements face problems of heterogeneity in composition, dosing, trial populations, and outcomes, producing underpowered studies and contradictory findings. Safety profiles for many OTC products remain underreported, and interactions with prescription drugs pose additional risks in older adults. The balance of current evidence supports using proven drugs and non‑pharmacologic interventions first, treating supplements as unproven adjuncts pending higher‑quality trials ^{[1] [4] [2]}.

6. Practical takeaways for clinicians and families navigating choices today

Clinicians should prioritize evidence‑based pharmacologic therapy where indicated, structured non‑drug approaches for behavior, and rigorous nutritional care to prevent malnutrition, while counseling families that OTC supplements lack reliable evidence for cognitive or behavioral benefits. Ongoing trials and planned network meta‑analyses may clarify which supplements, if any, warrant routine use, but current guidelines and reviews recommend caution and shared decision‑making. For now, the highest‑value actions are validated treatments and supportive care measures; supplements remain an area of research rather than a substitute for proven dementia management ^{[6] [5] [3]}.