There is a growing consensus that red meat, one of the bedrocks of the American diet, is also a leading cause of premature deaths in the United States:

An estimated 30 percent of the earth’s ice-free land is directly or indirectly involved in livestock production, according to the United Nations Food and Agriculture Organization, which also estimates that livestock production generates nearly a fifth of the world’s greenhouse gases – more than transportation does.

The study of more than 500,000 middle-aged and elderly Americans found that those who consumed about four ounces of red meat a day (the equivalent of about a small hamburger) were more than 30 percent more likely to die during the 10 years they were followed, mostly from heart disease and cancer. Sausage, cold cuts and other processed meats also increased the risk.

Previous research had found a link between red meat and an increased risk of heart disease and cancer, particularly colorectal cancer, but the new study is the first large examination of the relationship between eating meat and overall risk of death, and is by far the most detailed.

“The bottom line is we found an association between red meat and processed meat and an increased risk of mortality,” said Rashmi Sinha of the National Cancer Institute, who led the study published yesterday in the Archives of Internal Medicine.

In contrast, routine consumption of fish, chicken, turkey and other poultry decreased the risk of death by a small amount.

Not only is the consumption of red-meat products bad for human health, its production is wreaking havoc with the environment, because it:

• Uses over 90 percent of the agricultural land area in the United States — over half of the total land area of the country
• Uses hundreds of billions of gallons of water every day for crop irrigation
• Uses more energy per capita than the less developed countries spend per capita on energy for all purposes
• Produces soil erosion amounting to several billion tons of soil lost every year
• Is the major contributor to deforestation in the United States and in the tropical forests of Central and South America, where forests are being chopped down at the rate of 25 to 100 acres per minute

Despite the damage it causes human health and the global environment, the consumption of meat is rising throughout the developing world:

The world’s total meat supply was 71 million tons in 1961. In 2007, it was estimated to be 284 million tons. Per capita consumption has more than doubled over that period. (In the developing world, it rose twice as fast, doubling in the past 20 years.) World meat consumption is expected to double again by 2050, a projection that one expert, Henning Steinfeld of the United Nations, said was resulting in a “relentless growth in livestock production.”

Americans eat about the same amount of meat daily as they have for some time, about 8 ounces, or 230 grams, roughly twice the global average. At about 5 percent of the world’s population, Americans grow and kill nearly 10 billion animals a year, more than 15 percent of the world’s total.

Growing meat uses so many resources that it is a challenge to enumerate them all. But consider: An estimated 30 percent of the earth’s ice-free land is directly or indirectly involved in livestock production, according to the United Nations Food and Agriculture Organization, which also estimates that livestock production generates nearly a fifth of the world’s greenhouse gases – more than transportation does.

Of course, the reality is that nothing short of a shortage of meat, and the attendant escalation in price that would result, can slow the trend toward increased meat consumption worldwide.

On the other hand, there are few simpler (and cheaper) means available to Americans who want to improve their own personal health, as well as the health of the planet, than reducing or eliminating beef and pork from their diets.