This chapter explores bioaccumulation from food because of the importance of the route of exposure, especially in terrestrial systems where food can be the predominant source of contaminants to biota. Assimilation of a contaminant from food by individuals is one metric for estimating contaminant transfer between members of different trophic levels. It can be quantified as already described for bioavailability from food and used to estimate the magnitude of trophic transfer between the levels represented by the food item and consumer. In field surveys, the prevalent method for determining trophic status is gathering and integrating information from the natural history literature. This is adequate for interpreting results of some field surveys. Assimilation studies of metals and metalloids have used the twin tracer technique and single isotope differences between ingested and egested element.