New 'Triple Threat' Cause of Dementia Discovered

University of Michigan researchers followed people from age 18 through their 50s and 60s, tracking people with 'triple threat' habits - smoking daily, binge drinking or using cannabis frequently. A daily smoking habit in young adulthood predicted worse self-reported memory by age 50, regardless of whether the person had quit by age 35. For binge drinking and cannabis, the harm to memory was indirect: heavy use in young adulthood raised the odds of developing a substance use disorder by midlife, and that disorder directly damaged cognitive health.