Vitamin B₁₂, Folic Acid, and the Prevention of Dementia

Finding treatments for the prevention of dementia is an important challenge for medical research.1 Dementia currently affects about 4.5 million persons in the United States, and many more have cognitive impairment. The disorder is characterized by an insidious and progressive loss of memory and higher intellectual function, which ultimately leads to the inability of affected persons to live independently. The population distribution of cognitive impairment shows a continuum of severity, with dementia at one extreme of the distribution.1 Longitudinal, population-based studies of people who are 70 years of age or older show that cognitive function declines abruptly and irreversibly at . . .