At the debate on the health and ethics of eating meat last week, John Mackey and I argued that Stanford students could not ethically defend meat consumption and that eating meat is unhealthy.

Stanford student Ken Qin wonders why the topic is being debated and suggests that the discussion itself smacks of implicit bigotry.

In fact, the opposite is true: A fair-minded discussion of whether we should eat meat simply acknowledges that there are elements of meat production that are not immediately obvious. Upon closer examination, we find that raising animals for food violates at least three basic ethical precepts held by most (or perhaps all) members of the Stanford community.

First, eating meat is vastly wasteful. I imagine there are many readers who are concerned about the amount of food that is thrown away on campus, and yet eating meat is far more wasteful. In fact, eating meat entails throwing away 90 percent of the calories that went into its production, because the process requires at least nine calories in corn, wheat, and other feed to produce one calorie of meat. So each time someone consumes meat, they are essentially throwing away 8 calories for every calorie consumed.

This was my point in the article cited by Mr. Qin: Eating meat actually contributes to global poverty. As global hunger group Oxfam America explained, “eating less meat is a simple way to reduce the pressure on global resources and help ensure that everyone has enough to eat. To say it simply, eating less meat helps fight hunger.”

Second, eating meat is also extremely harmful environmentally. The United Nations looked at the process of meat production and came to the conclusion, which was spelled out over more than 400 pages, that meat production is “one of the top two or three most significant contributors to the most serious environmental problems, at every scale from local to global.”

On the issue of climate change, the U.N. study notes that meat production produces more CO2 than all planes, cars, buses, semi-trucks, and other forms of transportation combined. A study in the journal Nature points out that the most efficient meat produces 40 times more CO2 equivalent per calorie of protein than legumes, including soy. So each time any of us eats meat, we are doing exponentially more damage to the climate than if we were to choose plant-based foods instead.

Finally, eating meat causes animals to suffer and die. While it’s true that factory farms are especially egregious and that animals from such farms are treated in ways that would warrant felony charges were dogs or cats similarly abused, at the end of the day, there is absolutely no difference between eating a dog or a pig, a cat or a chicken.

For the same reason most readers would balk at the idea of eating Fido, no matter how well-treated he was, we should be similarly revolted by the idea of eating any animal. In short, eating meat entails eating an animal who has interests and a personality, and ethologists tell us that chickens and pigs outperform both dogs and cats on tests of behavioral and emotional complexity.

And for what?

Eating meat is linked to heart disease, cancer, diabetes, and obesity. According to the American Dietetic Association, plant-based diets are healthier than diets that include meat, dairy, and eggs. Not only are plant-based diets able to prevent some of the biggest killers in the western world, they can even be used to treat health problems like heart disease, obesity, and diabetes.

At the beginning of my presentation on the ethics of meat consumption, I asked the audience if they agreed that we should all be making decisions that align with ethical values favoring the environment, equity for the global poor, and kindness toward animals. Every single hand went up in response to all three questions.

So the question of whether we eat meat comes down to this: Should we be supporting a product that involves immense environmental harm, drives up food prices such that more people starve, and kills animals — and all while harming our own health.

That seems like a discussion that’s worth having, and I thank the Stanford community for inviting it.

Contact Bruce Friedrich at brucef ‘at’ thegoodfoodinstitute.org.