You can get human body model in Ansys EM 18 version. Best alternate way is design homogeneous body model with electrical equivalent properties of tissues. I think this will help you. if you want further doubts see the paper..
I would to share a research article written with the title "Optimal design of 6.1 GHz UWB antenna for off body communication"...with deals with the design of 6.1 GHz Ultra Wide Band (UWB) antenna for off body communication is fabricated and measured. The overall dimension of proposed antenna is 7×4×1 mm and mould by FR4 epoxy substrate material with dielectric loss tangent of 0.02..This work exclusively deals with SAR of on-off body communication..
You can check my research gate page...to get more info on it..
ANSYS HFSS version 18 has built-in human body parts and head phantoms with homogeneous permittivity and other properties. which can be readily used with any antenna for SAR simulations.