This study aimed to characterize the white matter biochemical profile of healthy elderly subjects, mild cognitive impairment (MCI) subjects, and early Alzheimer's disease (AD) patients. We used proton magnetic resonance spectroscopy ((1)H-MRS) to measure myo-inositol, creatine, N-acetylaspartate (NAA) and choline levels from a volume of interest located in the paratrigonal white matter bilaterally. A significantly higher myo-inositol/creatine ratio was found in MCI subjects and AD patients than in controls. The NAA/creatine ratio was reduced in AD patients in the left hemisphere compared to control subjects. The choline/creatine ratio was not significantly different among the three groups. These data suggest that MCI is different from normal brain aging, having a white matter biochemical pattern similar to AD.