Additional Study Information: MAP is a research study looking at whether metformin can help prevent memory decline for people with mild memory concerns. You may be able to join if: you are 55-90 years old, you or your loved ones have noticed some changes in your memory, and you are not already being treated for diabetes or dementia. Potential benefits: You will receive some of your blood test results. We can also share these results with your healthcare provider. Your participation may improve the prevention of dementia for future generations.