I personally don't bother that much about this in FbL, since I see it as a light survival game (compared to MYZ). One method that I think has been mentioned is to cap the number of steps that you can carry. The average number of rations (rolls) is:
d12: 11 rations (always at least four rations)
d10: 7,5 rations (always at least three rations)
d8: 4,5 rations (always at least two rations)
d6: 2 rations (always at least one ration)
If using the Alien variant instead, the average number of rations (rolls) is:
4d6: 11 rations
3d6: 9 rations
2d6: 6,5 rations
1d6: 3,5 rations
This way you only are guarantied one ration because you can roll multiple ones in a roll, but the chance of that is very small.