Abstract: Models of light interaction with matter usually rely on subsurface scattering approximations based on the use of phase functions - notably, the Henyey-Greenstein phase function and its variations. In this paper, we challenge the generalized use of these approximations, especially for organic materials, and propose the application of a data-oriented approach whenever reliable measured data is available. Our research is supported by comparisons involving the original measured data that motivated the use of phase functions in algorithmic simulations of tissue subsurface scattering. We hope that this investigation will help strengthen the biophysical basis required for the predictable rendering of organic materials.