diff --git a/code/material.f90 b/code/material.f90
index 4b9974e11..5002a08e9 100644
--- a/code/material.f90
+++ b/code/material.f90
@@ -1261,9 +1261,8 @@ subroutine material_populateGrains
        textureOfGrain = 0_pInt
        orientationOfGrain = 0.0_pReal
 
-       grain = 0_pInt
        texture: do i = 1_pInt,myNconstituents                                                       ! loop over constituents
-         grain            = grain + NgrainsOfConstituent(i-1_pInt)                                  ! set microstructure grain index of current constituent
+         grain            = sum(NgrainsOfConstituent(1_pInt:i-1_pInt))                              ! set microstructure grain index of current constituent
                                                                                                     ! "grain" points to start of this constituent's grain population
          constituentGrain = 0_pInt                                                                  ! constituent grain index