I gave up eating meat my junior year of college and since then I’ve been nearly ever flavor of vegetarian possible — from nearly vegan, which means not eating any animal products including milk or eggs, to not eating red meat but partaking of pretty much everything else.
One of the best changes that came from my initial decision was that it forced me to think more about what I ate. I couldn’t just mindlessly snarf down pizza while studying, I had to pause to consider the toppings. Some of favorite fast food crutches — Whoppers with cheese, Arby’s beef and cheddars — had to go, and in the early ’90s, there weren’t many drive-thru replacements for them. It was years until the advent of the ubiquitous veggie burger.
Since I’ve had about 20 years of practice explaining my diet to hosts and dining companions, I’ve gotten used to the frequent questions about why I don’t eat meat.
By way of explanation, I’ll point to a few recent articles about the American farming system:
* The New York Times wrote about flaws in U.S. inspection of beef
This lengthy article probes many reasons for outbreaks in food poisoning, including:

“the potential for contamination is present every step of the way, according to workers and federal inspectors. The cattle often arrive with smears of feedlot feces that harbor the E. coli pathogen, and the hide must be removed carefully to keep it off the meat. This is especially critical for trimmings sliced from the outer surface of the carcass.
Federal inspectors based at the plant are supposed to monitor the hide removal, but much can go wrong. Workers slicing away the hide can inadvertently spread feces to the meat, and large clamps that hold the hide during processing sometimes slip and smear the meat with feces, the workers and inspectors say.”

* President Obama bans “downer” cows from the food supply
AP reported on the president’s move in March:

The Obama administration on Saturday permanently banned the slaughter of cows too sick or weak to stand on their own, seeking to further minimize the chance that mad cow disease could enter the food supply.
The Agriculture Department proposed the ban last year after the biggest beef recall in U.S. history. The recall involved a Chino, Calif., slaughterhouse and “downer” cows.

What’s a downer cow? It’s an animal unable to stand on its own. Here a Humane Society video shows how such a cow might be treated when taken to slaughter.

[youtube=http://www.youtube.com/watch?v=zhlhSQ5z4V4]

* Undercover video shows male chicks ground up alive at an egg farm
This graphic video shows live chicks being tossed into a conveyor to be sent to death because they won’t lay eggs.
[youtube=http://www.youtube.com/watch?v=JJ–faib7to&feature=player_embedded]
Yes, to be honest, I still eat eggs. But that video has given me pause and I’m eating less.
* A New York Times magazine article about why the author gave up meat
Jonathan Safran Foer writes about his bumpy path to becoming a vegetarian, including the deep social and family connections he had with meat, beginning with a babysitter pointing out when he’s 9 that the chicken he’s eating used to be a chicken.
Later in the piece, he writes:

According to reports by the Food and Agriculture Organization of the U.N. and others, factory farming has made animal agriculture the No. 1 contributor to global warming (it is significantly more destructive than transportation alone), and one of the Top 2 or 3 causes of all of the most serious environmental problems, both global and local: air and water pollution, deforestation, loss of biodiversity. . . . Eating factory-farmed animals — which is to say virtually every piece of meat sold in supermarkets and prepared in restaurants — is almost certainly the single worst thing that humans do to the environment.
Every factory-farmed animal is, as a practice, treated in ways that would be illegal if it were a dog or a cat. Turkeys have been so genetically modified they are incapable of natural reproduction. To acknowledge that these things matter is not sentimental. It is a confrontation with the facts about animals and ourselves. We know these things matter.

The locavore eating movement is borne in part from people considering the implications of their eating decisions, including where and how food is grown.
I once had a political science professor who said he believed Americans would eat a lot less meat if they had to kill the animals themselves, instead of having it served up in a tidy little package divorced from what happened prior. I think being a conscious consumer requires thinking about what preceded a dinner and deciding whether you support it.
It’s not that I don’t know barbecued ribs taste great, or that I don’t miss salami. But when I consume those things, I endorse with my purchase everything that happened before my meal, and I can’t in good conscience do that.
Have you made any changes to your diet as a result of ethics or implications? Have you started eating more organic produce, for example, or given up veal or foie gras?