The use of glucagon-like peptide-1 (GLP-1) receptor agonists for weight loss is reshaping food demand, particularly for protein. This research estimates how GLP-1 use alters protein demand curves using methods of causal inference applied to structural demand modeling. Data from a public survey are balanced via matching to address endogenous selection into GLP-1 treatment. Demand shifts and rotations are then estimated using a discrete choice model and an Almost Ideal Demand System. GLP-1 use increases willingness-to-pay for most evaluated protein products, though the effects vary by product and outlet. Own-price elasticities for several retail products become up to 0.22 more inelastic. Our findings of shift effects of GLP-1 use on protein demand indicate externalities that are internal to the U.S. food system and that extend beyond simple consumption changes.
