This study uses the panel data of a randomized experiment from the Mexican PROGRESA program to evaluate the impact of drought on total calorie availability and the mitigating effects of PROGRESA on food consumption in periods of drought. Drought reduced total expenditures and total food expenditures but increased the total availability of calories. This paradox can be explained by the impact of drought on the composition of calories
that is, it reduced the consumption of expensive calories in such foods as vegetables, fruits, and animal products but increased calories consumed from cheaper sources, such as grains. This study finds that PROGRESA can completely mitigate the negative effects of drought on calorie availability from vegetables, fruits, and other sources. However, PROGRESA cannot mitigate the impact of drought on calories available from grains. The analysis also shows that, during drought, households who increase their consumption of grains get them mainly from purchased sources rather than from home production. In these circumstances, decreased total expenditures and increased purchases of grains suggest that grains are inferior goods in rural Mexico. The Engel curve analysis further proves that grains are inferior goods.