A groundbreaking study published in *The Journal of Prevention of Alzheimer’s Disease* has unveiled a concerning trend in China: the growth rate of young-onset dementia (YOD) is now significantly outpacing that of late-onset dementia (LOD). The research, which analyzed data from the Global Burden of Disease study spanning 1990 to 2021, highlights a critical shift in the burden of dementia across age groups. While the total number of LOD cases remains higher, the incidence and prevalence of YOD—defined as onset before age 65—have surged more sharply since 2012. This alarming trend underscores the urgent need for early intervention and preventive measures. Dr. Han Ying, a leading cognitive disorders specialist at Xuanwu Hospital in Beijing, emphasized that dementia prevention must begin as early as age 40, particularly for individuals in the prime of their careers and family responsibilities. The study also identified key modifiable risk factors for both YOD and LOD, including tobacco use, high fasting plasma glucose, and high body mass index (BMI). Notably, these risk factors exhibit significant gender-based variations, with tobacco use posing a greater threat to men and high glucose levels and BMI affecting women more severely. Dr. Han urged the public to adopt healthier lifestyles and prioritize brain health from midlife to mitigate these risks.