Can anyone help me decipher my MRI?

I am a 53 yr. old female who recently went to my family physician because I have been having headaches almost daily for a month. She ordered an MRI and there are no tumors but the results of the MRI showed cardiovascular changes in my brain. The test results say there are mild scattered subcortical gliosis likely secondary to chronic small vessel ischemic changes. No recent infarct, abnormal parenchymal enhancement, intracranial mass lesion, or mass effect. My Dr. told me that I need to make changes or a stroke or dementia could be in my future. He wants to put me on a daily aspirin and cholesterol meds. My question is can anyone tell me more about these test results and does this treatment sound right? He also mentioned diet changes and more exercise. Also he did say the headaches are not being caused by any of this. Any advice?