Challenges in studying meat consumption?

Studying meat consumption presents several challenges, particularly in isolating its effects from other factors. As discussed by Andrew Huberman, most studies find advantages among non-meat eaters in terms of lifespan or disease incidence. However, attributing these benefits directly to the absence of meat is complicated because people who choose not to eat meat often make other health-conscious decisions that are difficult to measure (1). Additionally, defining what constitutes 'meat' varies significantly, ranging from processed deli meat to grass-fed game, adding another layer of complexity to studies on meat consumption (1).