My neurologist said my mri indicated significatly more white matter on my brain for my age than normal. what does that mean?

Do you mean: more white matter signal abnormalities? There are many possibilities depending on the size/distribution of the lesions and your clinical picture, including demyelinating processes like multiple sclerosis, vasculitis, chronic small vessel vascular disease, and Lyme disease. You need to discuss the findings more fully with your neurologist. Take care.

Good: This is not a problem as best I can say,. Did your neurologist say it was a problem?