Epidemiology can only establish association, not causation, making it difficult to definitively link specific foods like red meat to cardiovascular disease.

“so epidemiology cannot differentiate from those two things it doesn't know which of those things could be doing it so you could also associate ice cream or you could associate mayonnaise or you could associate french fries with cardiovascular disease but epidemiology cannot draw a causative inference it can only tell us what are associated then we must test this with an interventional study”