Dementia Prevention Through Lifestyle Modification and Physical Activity: A Literature Review

Dementia is one of the most pressing health challenges in ageing populations. The World Health Organization (WHO) estimated that in 2019 about 55.2 million people were living with dementia, with projections rising to 65.7 million by 2030. Although no curative treatment currently exists, growing evidence highlights the key role of lifestyle-related factors in preventing dementia and delaying cognitive decline. This review synthesizes current knowledge on modifiable risk factors and outlines the pathophysiological mechanisms of its main subtypes, with a particular focus on physical activity. Literature was reviewed on the impact of physical activity, dietary patterns, sleep quality, cognitive stimulation, social interaction, and stress reduction on cognition and dementia risk. While most studies emphasize the neuroprotective role of physical activity, not all support a direct causal link. Additional emphasis is placed on the benefits of the Mediterranean diet and cardiometabolic disease prevention, both consistently associated with reduced dementia risk, especially of vascular origin. The DASH diet, designed to reduce hypertension, has also been linked to cognitive benefits. The review further highlights the importance of adequate sleep, sufficient vitamin D levels, and regular participation in intellectually and socially engaging activities. Concerns are also raised about excessive screen time and low-quality digital content, which may negatively impact cognitive health. The overall evidence supports integrated health and social strategies promoting healthy lifestyle behaviours as effective, scalable, and realistic approaches to lowering dementia risk and enhancing cognitive resilience in older adults.