Vegans are a group of people who, by definition, are vegetarians that eat only plant products and don't use anything derived from animals, such as leather.

So what is it about this movement that draws such ire from people? Exploding in popularity among all sorts of people -- from politicians to celebrities to school children and athletes -- veganism has moved from the fringe into the mainstream. Now, some vegans are self-righteous, lecturing, soap-boxing, holier-than-thou activists. Trust me, I have been a committed vegan for more than 25 years and there are those within the movement that cause me to roll my eyes and pray that no one is listening.

However, most of the vegans I know are soft-spoken, loving, kind, compassionate and committed to living a life that is kind to all beings and to the planet. It's a powerfully simple sentiment imbued with only good intentions.

And yet, this gentle movement that promotes the consumption of a plant-based diet, living a healthier life and leaving a lighter footprint on the planet evokes rage like I have never seen. Just read the comments on this very website whenever an article talking about veganism is posted. They can make your hair curl! The rage and indignation over someone's endorsement of a plant-based diet is mind-boggling to me.

It has made me stop and think what this rage is all about. Being openly vegan all these years, I am often in the company of people who feel the need to justify their food choices. I wish I had a nickel for every "I don't eat as much red meat as I used to" that I hear during a social gathering.

As a food and health activist, I am deeply committed to healthy food choices for all people. Wholesome foods and clean water are the birthright of all Americans ... all world citizens. But because as a society we depend so heavily on an animal-based diet, no small number of people are denied that very basic right. But I am not sure that the anger is about guilt or justification.

Georges Ohsawa, a Japanese philosopher once said that when we take more than our fair share of food, we damage all of humanity with our greed. In my view, when we choose to eat commercially manufactured meat (yes, manufactured because there ain't anything natural about factory farming), we contribute to world hunger. We deprive people of food because acre after acre of land is farmed to produce animal food and animals for food.

You can say we should be eating like our Paleolithic ancestors. You can say that commercial agriculture is also to blame for the razing of land and pollution (you would be right, but not to the degree animal food production does). You can say that it's different for you because you only eat meat from a small family farm and meat production is the lifeblood of the small rural farm. Without meat, they would go under (a stretch ... there are lots of things they can grow besides producing meat and dairy, but farmers produce what the market demands). I don't believe that any of these things prove that we are not overly dependent on animal products as a society.

According to the Food and Agriculture Organization, "producing animal-based food is typically much less efficient than the harvesting of grains, vegetables, legumes, seeds and fruit for direct human consumption." The chefs, farmers and sustainable food producers at Sustainable Table add that most water pollution from industrial farms results from the storage and disposal of animal waste.

Ultimately, producing meat is not so healthy for the planet. And for us? Well, not so much either.

So is it collective guilt that makes people so mad at vegans and the idea of eating a plant-based diet? I have seen mean-spirited comments on blogs posts supporting veganism that range from telling the author to "man up" to vegan members of food co-ops being accused of having "an agenda" because they do not want to sell meat. The comments range from fear-mongering warnings about vitamin B-12 deficiency (and other nutritional deficits of a plant-based diet) to the rationalization that "animals, including their use as food, are a necessary component of sustainable agriculture" according to a UN report -- a quote that is taken out of context.

The UNEP report from June 2010 calls for reduced meat consumption and a move toward a plant-based diet to curb pollution and sustain population growth. http://www¬.unep.fr/s¬hared/publ¬ications/p¬df/DTIx126¬2xPA-Prior¬ityProduct¬sAndMateri¬als_Report¬.pdft

So I am back to my original question: Why do people get so mad at the idea of living a healthy, compassionate life and not harming animals or other living things in the process of doing so?

I know there will be comments on this piece about how unhealthy a vegan diet is for people. There may even be links to the recent New York Times article that gorillas in Uganda do not experience obesity or other 'lifestyle' diseases because of their high protein diet, with an intake of protein akin to an Atkins-style diet -- 17 percent of their daily calories to be exact.

And where does that protein com from? "Protein-rich leaves dominate the gorilla's diet." Not so Atkins-like after all. You won't see gorillas chowing down on Big Macs (without the buns, in true Atkins style). And while the typical high protein diet, like the one developed by Dr. Atkins also supports the eating of green leafy veggies, it's hardly that diet that keeps gorillas from the grips of obesity. It's the plants they eat.

In the end, I have come to the conclusion that the derision and ire evoked by articles about veganism is simply a reaction to expressing an opinion that differs from the mainstream. I believe these reactions will continue to proliferate as long as we keep being told that meat is a necessary component of human health.