Questions have arisen as to the effect of diversion of soybean oil to biodiesel.  It is estimated that in 2020, 43 percent of U.S. soybean oil was used to produce vehicle fuel.  Since the fall of 2020, soybean oil prices have doubled.

A study conducted by an agricultural economist commissioned by the biofuels industry projected that a 20 percent increase in diversion of soybean oil to biofuels increased the wholesale price of cooking oil by 4.4 percent but less than one percent for frying oil, and margarine.

With respect to egg production, increased demand for soy oil depresses the price of soybean meal based on supply to demand relationships. However increased diversion of soy oil to biodiesel creates a demand for soybeans to be crushed and thereby raises the price of soybeans. In response, farmers tend to plant more beans at the expense of corn acreage resulting in higher prices of corn and DDGS. Diversion of food to fuel increases the cost to produce livestock and eggs. Biofuels derived from corn and soybeans represent a tax on all who eat. The effect of drought in the U.S. or any noteworthy reduction in world supply of feed commodities due to weather or conflict accentuates the deleterious impact of biofuels.