Elderly people with higher levels of vitamin B12 had lower risk for dementia and mental (cognitive) impairment in a new study. Researchers from the University of Michigan in Ann Arbor, followed 1,405 Mexican-Americans aged 60 to 101 for an average of 4.5 years and found that those who had higher levels of vitamin B12 had lower levels of a risk factor—homocysteine—for Alzheimer’s disease, dementia and cognitive impairment. Those who had high homocysteine levels were 139% more likely to develop dementia and cognitive impairment, and those who had both high homocysteine levels and low vitamin B12 levels had even greater risk of cognitive decline.