Dementia prevention requires moving beyond individual choice: the costs of effort and time intersect with social determinants of health.

Social determinants of health strongly influence modifiable risk factors for dementia, yet prevention frameworks list only individual-level behaviours and conditions, overlooking the impact of social and environmental factors on the risk of dementia. In this perspective, we introduce the concept of non-monetary costs as a central mechanism through which social determinants shape modifiable risk factors by influencing individuals' ability to adopt healthy behaviours. Drawing from economic theory, we define non-monetary costs as the time and metabolic cost, perceived by individuals as physical and cognitive effort, required to engage in healthy behaviours. Under adverse social determinants of health, individuals effectively lack choice, as the non-monetary costs required to engage in healthy behaviours become prohibitively high. We propose a framework that links social determinants of health adversity to increased dementia risk through non-monetary costs. We apply this framework to each of the fourteen modifiable risk factors for dementia identified by the Lancet Commission, demonstrating how these costs systematically elevate risk in populations facing social adversity. Finally, we explore the implications of incorporating non-monetary cost assessments across research, interventions, clinical care, and public policy. We propose that quantifying and addressing these costs is essential for designing equitable, scalable, and contextually grounded strategies for dementia prevention across socially diverse populations.