Controversial new lab-grown meat has been slammed by nutritionists and farmers skeptical of its nutritional value – and whether it should even be labelled as beef or chicken.

The US Department of Agriculture and the Food and Drug Administration have given the green light to two companies, UPSIDE Foods and GOOD Meat, to sell their products — which are cultivated in a lab rather than coming from slaughtered animals — in the US.

The meat is created from live stem cells taken from the muscle and skin of real live animals, which are then cultivated in a bioreactor, a process which emulates conditions in an animal’s body and feeds the cells nutrients in order to “grow” the meat.

But that process leaves a bad taste in many professionals’ mouths.

“I’d rather eat my shoe than lab-grown meat,” said well-known nutritionist and food author Diana Rodgers in an interview with The Post.

She argues the best type of meat comes from farms where animals are allowed to graze and raised outside of the industrial food system, where animals are brought up in over-cramped conditions and pumped full of hormones.

It’s also expensive, Rodgers pointed out. A pound of cell-cultured meat would cost about $17 to make, compared to $2 for regular meat, according to Bon Appetit.

By the time lab-grown beef gets onto a plate at a restaurant that could could turn into a $100 burger, the publication calculated.

Because of a lack of available nutritional information on lab-grown meat, Rodgers could not say how healthy cell-cultured meat is.

“We just don’t know,” Rodgers explained. “I have yet to see a life cycle assessment on the production of it. We don’t have any public data.”

“McDonald’s is still better because the meat is a better option for vitamins,” she added.

For its part, the National Cattlemen’s Beef Association is pressuring the FDA to stop the companies producing the lab-grown meat from using conventional names — claiming the description ‘beef’ should be reserved for meat which comes from animals raised as livestock.

GOOD Meat told The Post its product is made of chicken cells, salt and a combined base product of wheat and soy, but there is no nutritional label available for it at this time, as its product will only be available at restaurants for now.

Washington DC eatery China-Chilcano, a José Andrés restaurant, and Michelin starred Bar Crenn in San Francisco will be to first to serve up the alternative protein.

“GOOD Meat cultivated chicken is high in protein, including essential amino acids,” a spokesman said in an emailed response.

“It is also high in B vitamins and is produced in an antibiotic-free environment. The specific nutrition profile varies for each of our consumer products. We use unmodified (non-GMO) chicken cells, which occur naturally in animals. Our manufacturing process doesn’t use antibiotics either.”

UPSIDE Foods explained their product is real meat, digested by humans just like any conventional meat.

The lab grown meats are not to be confused with meat alternatives offfered by companies such as Beyond Meat or Impossible Foods, which re-create the taste and textures of meats using plant products.

The company shared a memo from the FDA which says its cell meat, which comes from adult chickens or fertilized eggs, is as safe as regular chicken.

UPSIDE also shared the 140-page document it had submitted to the FDA, where it painstaking details how its chicken is made, how the cells are harvested and its genetic amendments.

However the documents do not include nutritional information.

“They’re taking mono-crop plant sources, taking them into a factory and using high-energy processes to convert them into meat,” said Rodgers.

She insisted food in its most natural state is the healthiest and most nutritious — pointing to what what regenerative farmers like Thomas Locke is doing on his farm north of Dallas.

He practices what most people would consider good-old fashioned farming, where the animals he raises graze green pastures. He plants crops that will restore the soil and let it heal from past use of chemicals or man-made fertilizers.

“The answer is not going to be found by making fake meat in a vat; it’s going to be found by re-embracing the laws of nature,” Locke said.

He pointed to a UC Davis study that concluded the carbon footprint of cell-cultured meat could actually be worse than industrial meat production.

Lab-grown meat companies often market themselves as a more Earth friendly option than industrial beef production.

“There’s so much money to be made in fake meat,” the Texas farmer said. “Silicone Valley and venture capitalist have invested billions of dollars in this and they’re not doing it out of the goodness of their hearts. They’re doing it because they’re planning on making so much money of it.”