In this paper, the benefits of using MIMO in body-centric wireless communication channels are evaluated by quantifying the correlation and capacity increase of various on-body channels for both the narrowband and the ultrawideband (UWB) frequency range. The correlation between the sub-channels are evaluated and the achievable channel capacity of a 2×2 MIMO on-body channel is compared to the SIMO and SISO case. It is found that narrowband MIMO outperforms narrowband SIMO and SISO after a certain signal-to-noise (SNR) level, with an average improvement of 1.5 bps/Hz versus SIMO and 2.5 bps/Hz improvement versus SISO for the Wrist-Waist channel. For the UWB scenario, the average improvement of MIMO versus SIMO and SISO is 4 bps/Hz and 5.5 bps/Hz, respectively, for the Wrist-Waist channel.