Midlife Vitamin D Levels Tied to Lower Dementia Risk, Study Shows

A Neurology study of 793 adults in their 30s–40s followed for 16 years found higher vitamin D in midlife associated with lower brain tau protein, a dementia-related marker, though amyloid levels weren’t affected and causality isn’t proven. With roughly 60% worldwide deficiency, researchers advise correcting vitamin D deficits and adopting brain-healthy habits—diet (fatty fish), regular physical activity, social and cognitive engagement, and managing vascular risks like diabetes, high blood pressure, and cholesterol—to support cognitive health later in life.