Food expenditures and subsistence quantities of poverty status and non-poverty status US households are analysed within a Linear Expenditure System that postulates subsistence quantities to be linear combinations of demographic variables. Using the US Bureau of Labor Statistics' 1992 Consumer Expenditure Survey and Detailed Monthly Consumer Price Indices, this article obtains expenditure elasticities, own-price elasticities and subsistence quantities for each income group across nine broadly aggregated food commodity groups. Elasticity estimates and subsistence quantity estimates differ across income groups, supporting the premise that policies targeted at specific income groups should be based on the target group's elasticity estimates rather than average population elasticities. Parameter estimates are then used to simulate how subsistence quantities and own-price elasticities can be expected to vary according to the demographic composition of the household within a specific income group.