White matter hyperintensities—bright lesions visible on brain MRI scans originating from small vessel damage—demonstrate measurable contribution to Alzheimer's disease progression beyond their previously understood role as incidental age-related findings. These vascular-origin markers appear earlier in disease development than classic amyloid and tau pathology, suggesting a window for intervention. The vascular hypothesis of cognitive decline gains substantial support through this connection, positioning cerebrovascular health as a potentially modifiable risk factor rather than merely a comorbid condition. For health-conscious adults, this represents a paradigm shift toward preventive strategies targeting cardiovascular wellness—through blood pressure management, exercise, and anti-inflammatory approaches—as neuroprotective measures. The finding bridges two major theories of neurodegeneration: vascular dysfunction and protein aggregation. However, the observational nature of current evidence limits causal interpretation, and therapeutic trials specifically targeting white matter lesion reduction remain preliminary. This vascular-cognitive connection may prove especially relevant for individuals with hypertension, diabetes, or other cardiovascular risk factors, potentially expanding the population who could benefit from early intervention beyond those with genetic Alzheimer's predisposition.