Yet when Michael Pollan speaks in Salt Lake City on Thursday, he'll do so not in a cramped bookstore or a snoozy university classroom but at glittering, 2,768-seat Abravanel Hall, where tickets are selling briskly at $10 a pop. Such mass appeal is extraordinary for a literary author, even one with the top-selling nonfiction book in the country.

That's because Pollan writes about food - a subject everyone relates to and has strong opinions about. His 2006 book, The Omnivore's Dilemma, followed four major food chains from their origins to their final stages on the dinner table. His new best-seller, In Defense of Food: An Eater's Manifesto, poses that Americans would be healthier if they ate less processed, prepackaged food and more fresh meat, fish, fruits, vegetables and whole grains - in other words, the stuff our great-grandparents would recognize as food.

"I don't think it's just me," says Pollan of his skyrocketing popularity. "There is something going on the culture around food right now. There is a movement rising. I've been speaking all over the country in the last two months, and the audiences have been huge, and the fervor, the energy surrounding this issue is really astonishing. There is deep concern about food. There's this sense that the industrial food chain is not serving us well."

Pollan blames this unease on several factors: One is the corporate food industry, which he says in recent decades has emphasized processed - and highly profitable - food products that are low in nutrients but high in sugar and fat. Another is confusing nutrition science, much of it funded by the food producers themselves, that promotes "healthy" alternatives, such as margarine, that end up being more harmful to us than the foods they were intended to replace.

No coincidence: Pollan believes that decades of cheap industrial food and unreliable nutrition science - he calls it "nutritionism" - have combined to make Americans increasingly overweight and more susceptible to such illnesses as diabetes and heart disease. At the same time, he says, the food industry's powerful lobbies have kept the government from labeling certain foods as unhealthy.

In Defense of Food's most alarming statistic might be this: In 1960, Americans spent 17.5 percent of the national income on food and 5.2 percent on health care. Today, spending on food has dropped to 9.9 percent of national income, while health-care spending has climbed to 16 percent. To Pollan, that's not a coincidence.

"If we could spend more to eat healthy food, we could, I am certain, spend less on health care. Because eating this cheap food is contributing to this public health crisis," he says by phone from his home in Berkeley, Calif., where interviewers have been known to peek in his fridge to see if he practices what he preaches.

"We've seen that the government really cannot speak plainly about food, because the food industry does not allow it. If the government had to pick up the tab for all the obesity and diabetes and heart disease that the food industry is causing, we'd hear very different messages. The government would have a very strong interest in getting out the truth about how to eat. They'd have to say that, or they'd go broke."

Fresh sources: Pollan believes that more and more Americans, driven by health and environmental concerns, are beginning to question where their food comes from and what's in it. He cites the growing popularity of organic foods, farmers' markets and CSAs (community-supported agriculture, in which people subscribe to a small farm and receive a weekly box of produce) as evidence that people are yearning for fresh, local sources of food. Pollan gets most of his food from farmer's markets, CSAs and his own garden, although he visits supermarkets for such staples as cat food and laundry detergent.

Admittedly, that's easy for him to say: Pollan lives in San Francisco's East Bay, where the weather is mild and farmer's markets operate year-round. It's a lot tougher to find fresh, organic food when you live in colder climates or rural areas with no Whole Foods. Healthy food also costs more, which prices it out of reach of lower-income consumers.

"That's the big challenge of this [food] movement - how to make it affordable to the people who need it the most," says Ian Brandt, chef and owner of Sage's Cafe, a Salt Lake City restaurant that serves organic vegetarian cuisine. "Try telling a poverty-stricken neighborhood to eat less canned food . . . when they're struggling to survive."

But Pollan suggests that people who spend more for fresh, healthy food over the long term will save money on doctors' bills. He recommends that people without year-round farmers' markets compensate by buying fresh food in season and preserving it through canning or freezing. And he believes healthy food can still be found around the perimeters of conventional supermarkets, which tend to line their walls with fresh meat and produce.

"We're a culture that consumes too much of the wrong things and not enough of the right things," agrees Steve Rosenberg, owner of Salt Lake City's Liberty Heights Fresh market and an avid reader of Pollan's books. "No matter how you eat, there's something you can take from [In Defense of Food] that will improve your health and the quality of your life."

Common sense: Pollan's advice is more common-sensical than groundbreaking and can be summed up by the first seven words of his new book: "Eat food. Not so much. Mostly plants." By "eat food," he means fresh food instead of processed "edible foodlike substances." By "not so much," he means to avoid overeating, which can contribute to such diseases as diabetes. And by "mostly plants," he means leafy vegetables rich in antioxidants.

He also urges Americans to savor the pleasures of food by eating more meals around a table, as opposed to in front of a TV or in the car, and to eat more leisurely - perhaps an impossibility in today's time-pressed society.

But Pollan is reluctant to dictate anybody's menu. No vegan ascetic, he owns a microwave and admits to having a spray can of whipped cream in his refrigerator. Asked what he'd request for a last meal, he envisions a grass-fed sirloin steak, new potatoes, sauteed greens and a few glasses of cabernet.

"I don't feel a journalist can tell you how to eat. What I want to do is give people some tools, so they can make their own decisions," he says. "I don't think we can wait for the [food] industry or the government to rescue us. We have to rescue ourselves. We need to change. And hopefully in 100 years we will have turned away from this diet and gone back to a way of eating that left us much more healthy."

griggs@sltrib.com