Kelly and Rick Mooney are avid University of Oregon tailgaters.

Kelly brother “Mad Dog” wrestled there, and back in the day both the Cowboys and the Redskins drafted her dad, Duck guard, “Big Guy” Maloney. Kelly didn’t do sports, but she did do brew. She was U of O Beer Bong Champion, 1986.

Rick heli-skis and races cars, as did his oil-and-gas entrepreneur dad. Kelly and Rick have an aviation-obsessed, football-playing son, a go-cart racing daughter and two adorable dogs.  They also happen to be vegans.

The popularity of eating vegan -- no meat, fish, dairy, eggs, honey -- has exploded in recent years.  According to a new Gallup poll 2 percent of Americans say they are vegans, eschewing all products made with and from animals, even bees.

Celebrities and politicos, such as Anne Hathaway, Bill Clinton and Michelle Pfeiffer proudly discuss their plant-based dietary habits, and veganism has even spread into space, as NASA scientists work on a vegan menu for the astronauts who will blast off to Mars on a trip planned for 2030.

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But as the popularity of veganism grows, some warn of the faddish hype of veganism, adding that their public image is militant as they preach the sins of consuming animals and their by-products for commercial, dietary or environmental reasons.

As more Americans switch to veganism, determining its benefits  --both in terms of health and taste --can be confusing.

We talked to four experts who weighed in on the pros and cons.

Well, they’re not switching for taste, says Nina Planck, who like the meat and poultry she devours, was farm-raised. “Vegan food is lousy,” says Planck, author of the popular Real Food (Bloomsbury USA) cookbook series. “They have bad taste in food.”

She says veganism is about replacing what’s at “the center of plate” with substitutions “like soy turkey” or “soy cheese.” Plus, she says, vegans annoyingly “tweak worldwide classics, like pesto.” They’ll use “raw spinach, raw cashews and canola oil” instead of the Parmesan, basil, pine nuts and olive oil of traditional pesto. “Why?” she asks.

Wild About Greens (Sterling) author Nava Atlas acknowledges vegan meat and dairy substitutes, but points out that veganism embraces meat-free elements from many cultures. She points to Italian pasta, Middle Eastern hummus and Southwestern rice, beans and tortillas. “There’s an integrity to vegan cooking that doesn’t require substitutes.”

Vegans get protein from quinoa, a South American grain, tofu, soy and almond milks, beans, peas, nuts, lentils and whole grains. Learning to cook with them “expands your whole culinary palate,” she says, proving that plant-based cooking is more than “a narrow path of vegetable and starches.”

Planck’s beef with veganism goes beyond taste. It doesn’t do a body good, she argues. Especially at key stages of life “including, fertility, breast feeding and infant development, veganism is harmful to health,” she says.

Grains and vegetable oils (corn, soybean, canola) are our main sources of omega-6s, says Planck. Too much omega-6 can ignite the inflammatory conditions that contribute to cancer, heart disease and diabetes. Veganism excludes omega-3 (from fish), B-12 (from meat) and vitamin D (from dairy) says Planck, and “doesn’t sustain good health over the long run without synthetics.”

“That’s a complete myth,” says vegan nutritionist Julieanna Hever, author of The Complete Idiot’s Guide to Plant-Based Nutrition (Alpha Penguin). Yes, vegan diets lack natural B-12, she says, but there are as many poor omnivorous diets as vegan ones. Flax and walnuts provide omega-3s, she says, and fortified soy and almond milks, and cereals, supply D.

Meat’s vital nutrients come with steroids, hormones, antibiotics and pesticides. “You can’t change that,” says Hever. “That animal spent its life eating those things,” she says. Don’t eat the animal and you avoid the health issues eating the animal causes: obesity, high-blood pressure, etc.

Explaining that she’d have to pry a burger-and-shake out of her cold, dead hands, Hever good-naturely says that’s okay as long as her diet is “ninety-percent plant-based.”

Vegans’ “do no harm” animal credo, which doesn’t distinguish between animals as pets and animals as commodities, does convince some omnivores to switch teams.

Will Harris III isn’t buying it. Animals are sacrificed “for purpose of giving nutrition to people,” says Harris, fourth-generation owner of Bluffton, Georgia’s White Oak Pastures, the only American farm with its own USDA-inspected red meat and poultry slaughter plants.

He understands that some people can’t get past the idea that animals can be raised and humanely slaughtered. “We evolved, or were created, to eat meat,” he says. He says we have teeth for tearing and “our eyes are mounted in front like predators, not the side, like prey.”

Harris acknowledges studies showing that meat consumption contributes to cancer and cardiovascular disease. “I defer to the science,” he says, but says those studies are based on industrially-raised livestock.

They’re based on industrial animals eating corn and soy and “dying of obesity and inactivity,” he says. Studies show that organic, free-range, grass-fed animals like Harris’ contain B and C vitamins, beta-carotene, amino acids, omega-3s and are lower in fat. “All the work that shows that meat is bad for you isn’t done with the kind of meat I raise,” he says simply.

Vegan diets with their compassionate stance towards animals are gaining traction. Convert Kelly Mooney is holding fast for now. Based largely on veganism’s compassionate stance towards beer.