The primary argument for insect farming is environmental: promoters argue that insects have a smaller resource and carbon footprint than other animals raised for meat. This argument rests on insects' incredible efficiency: in theory, they can convert just 2.3 pounds of dry food waste into a pound of edible meat.
But this isn’t what the industry is actually doing. Most insect farms use grains, not food waste, likely for the same reasons most chicken and pig farms do: grains are cheaper, safer, easier to source, and spur faster growth. The few large insect farms marketing their use of “food waste” seem to actually be using high-quality agricultural byproducts, like corn meal and distillers grain, which would otherwise be fed to farm animals.
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