The preprint study, which has yet to undergo peer review, concludes that the energy needed and greenhouse gasses emitted during all stages of production of lab-grown meat is far greater than traditionally raised beef.

Researchers conducted a life-cycle assessment of the energy needed and greenhouse gases emitted in all stages of production and compared that with beef. One of the current challenges with lab-grown meat is the use of highly refined or purified growth media, the ingredients needed to help animal cells multiply. Currently, this method is similar to the biotechnology used to make pharmaceuticals. This sets up a critical question for cultured meat production: Is it a pharmaceutical product or a food product? –UC Davis

"If companies are having to purify growth media to pharmaceutical levels, it uses more resources, which then increases global warming potential," according to lead author and doctoral graduate Derrick Risner, of the US Davis Department of Food Science and Technology. "If this product continues to be produced using the "pharma" approach, it's going to be worse for the environment and more expensive than conventional beef production."

The scientists considered the 'global warming potential' to be the carbon dioxide equivalents emitted for each kilogram of meat produced – and found that the global warming potential of lab-based meat using these purified media is up to 25 times greater than the average for retail beef.