Omega-3 Fatty Acids in Alzheimer’s Disease Prevention Among Elderly Women: Mechanisms of Action, Clinical Evidence, and the Critical Role of Early Intervention

Introduction: Alzheimer’s disease (AD) is the most common cause of dementia in older people, characterised by progressive cognitive decline, memory loss and impaired executive function. Its pathophysiology includes beta-amyloid plaque accumulation, tangling of Tau proteins, chronic neuroinflammation and dysfunction of the glymphatic system. Older women, especially postmenopausal women, are at increased risk for AD due to estrogen deficiency and metabolic changes. Purpose: The purpose of this narrative review was to investigate the protective role of omega-3 fatty acids, in particular docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), in the prevention or slowing of AD progression in older women. The review focused on the nutritional, neuroprotective and anti-inflammatory effects of omega-3 and the interaction of these substances with hormonal and genetic factors. Methods: A comprehensive text search was conducted across PubMed, Scopus, Web of Science, Google Scholar, and ScienceDirect databases for articles published to 2025. Seventy-eight quality English-language studies involving human and animal models were selected for qualitative analysis. Results: The findings indicate that DHA and EPA may reduce inflammation in the brain, promote integrity of the neuronal membranes and facilitate clearance of neurotoxic proteins such as beta-amyloid. These benefits are especially important in women after the menopause. Regular intake of omega-3 fatty acids via diet or supplements has been associated with improvements in memory, attention and reduced cognitive decline. In addition, genetic variations such as the allele APOE-ϵ4 can modulate individual responses to omega-3 supplementation. Conclusion: In conclusion, omega-3 fatty acids are a promising, non-invasive and cost-effective strategy to reduce the risk of Alzheimer’s in ageing women. Monitoring of omega-3 levels and their integration into public health strategies after menopause is strongly recommended. Plain Language Summary: This narrative review examines whether omega-3 fatty acids, in particular DHA and EPA, may be involved in the development of Alzheimer’s disease in the elderly, with a focus on its biology, cognition and clinical consequences. Why this study was conducted? Alzheimer’s disease is the leading cause of dementia in the elderly, and is driven by beta amyloid plaques, tau tangles, chronic neuroinflammation and glymphatic dysfunction. Postmenopausal loss of estrogens and metabolic changes increase the risk in older women, and the use of omega-3 is highlighted as a potential and achievable intervention. What the researchers did and found? Methods: A narrative review of 78 English-language studies (human and animal) to 2025, retrieved from PubMed, Scopus, Web of Science, Google Scholar, and ScienceDirect. Key findings : DHA and EPA can reduce inflammation in the brain, strengthen the neuronal membranes and help to clear beta-amyloid from the blood. Regular intake of omega-3 (diet or supplementation) has been associated with improved memory and attention and slower cognitive decline, especially in postmenopausal women. Genetic factors, especially APOE-ϵ4, may modulate the omega-3 response; some genotypes may be more beneficial than others. The benefits may depend on the continuous intake and may interact with hormonal and metabolic states. Implications of these results: Omega-3 is a promising, non-invasive and cost-effective strategy for potentially reducing the risk of Alzheimer’s disease and improving cognition in older women. Public health strategies could include monitoring of omega-3 status and the promotion of dietary and supplemental sources, taking into account individual genetic and hormonal predispositions. Keywords: Alzheimer’s disease, women, postmenopausal, aging, neuroinflammation, omega-3 fatty acids, DHA, EPA