A high body mass index is known to play a role in a variety of chronic diseases, which makes it an important biomarker. Using a 3D two-point quantitative mapping method, changes in several parameters including relaxation times, H2O and magnetisation transfer measures were investigated in lean and obese subjects. Preliminary results show a significant increase of H2O in corpus callosum (p<0.05), thalamus (p<0.005) and white matter of temporal lobe (p<0.05) with increasing BMI. Changes in the other parameters did not reach significance. These findings suggest the existence of regional low-grade brain inflammation in obesity.