With the National Cancer Institute's warning this week that red meat is bad for people, a nutritionist from University of North Carolina at Chapel Hill added his view that it's also unhealthy for the planet.
Barry Popkin, a professor of nutrition, in an editorial published this week in the Archives of Internal Medicine, makes the case to ratchet back meat production and consumption.
"The costs may be greater for the planet than for people," Popkin says, noting that increased demand for beef, pork and other red meats strains environmental systems, particularly scarce water resources that get diverted to livestock.
Is meat bad? Here's how scientists at the National Cancer Institute came to their conclusion: The study surveyed 500,000 people between the ages of 50 and 71 about their eating, exercise, smoking, drinking and other health habits.
People had higher death rates from cancer and heart disease if they were in the group that ate a lot of red meat; processed meats such as bacon and hot dogs were especially troublesome.
A slightly reduced risk of death was noted among people who ate white meat.
Popkin's commentary, which immediately drew criticism from meat producers, accompanies a study in the same journal that links high meat consumption with increased death rates from cancer and heart disease among older Americans.
The individual costs of eating meat must also be measured against the global consequences, Popkin argues. He says large-scale industrial meat production takes too much energy, food and water to remain practical.
Although he doesn't advocate vegetarianism, he says people can help themselves, and the global environment, by scaling back their appetite for meat.
Beef and pork producers counter that they are being unfairly targeted.
Dr. Jennifer Greiner, a veterinarian and director of science and technology for the National Pork Producers Council, says the health studies divert attention from obesity, inactivity and a lack of access to good care that are equally important to health.
A spokesman for the National Cattlemen's Beef Association said ranchers are good stewards of the environment and should not be lumped in with agricultural interests in areas such as South America, where great swaths of rain forest are wiped out to create cropland and pastures.
"The fact is, beef production is very sustainable," said Daren R. Williams, executive director of communications for the cattlemen's group. "We're taking inedible forage land and turning it into one of nature's best-tasting multivitamins."