FEW FOOD writers have done more to make vegans both cheer and grumble than Mark Bittman.

Certainly, the guy knows food, particularly the plant-based kind. He's a columnist for the New York Times Dining section and the lead food writer for the Sunday magazine. He writes for the Times opinion page and blogs, too. He also wrote the best-seller How to Cook Everything.

Leafy greens are a trendy topic now, but Bittman wrote the book on 'em back in 1995 (see here). He's done a vegetarian cookbook and has examined some of the problems associated with overconsumption of meat.

Last July, he slammed the dairy industry, busting the ad claim that drinking milk prevents osteoporosis and sharing how his heartburn disappeared when he went milk-free.

But Bittman is neither vegan nor vegetarian, which frustrates many animal-free foodies who'd love to count the outspoken straight-shooter as one of our own.

With his new book, VB6 (Clarkson Potter), Bittman pumps up that jam by suggesting that readers eat completely plant-based - until 6 p.m., when they can literally pig out. The book's full subtitle, Eat Vegan Before 6:00 to Lose Weight and Restore Your Health . . . for Good, marks its straightforward focus on health, although there's enough consideration of wider concerns to keep ethical vegans cheering - and grumbling.

An unprocessed life

When his doctor said to him, after some troubling blood work, "You should probably become a vegan," Bittman searched for a regimen that could improve his numbers and his weight while still allowing him to indulge in the foods he enjoyed most.

His only-after-6 approach isn't quite that simple, of course. The book could be called VUB6, because he also emphasizes unprocessed foods. It's not as though he's suggesting you eat Tofurky sausage for breakfast and Tofutti pizza for lunch, then fall "back" into an eat-everything dinner.

And even the B6 part has some wiggle room, as the plan is designed for individual customization. In an email exchange, I asked him how he went from one simple idea to a system whose kinks he'd worked out to the point that it was book-worthy.

"Really, I just started, plunged in without much of a clue," Bittman wrote back. "I believe any similar strategy that got me eating more plants and less other stuff would've worked. But this was easy and fine - after six weeks, I'd lost a bunch of weight and after 12 weeks my blood levels were all good. Both of those were stable for five years, and that's when I decided to write a book about it."

You can cheat here and there, and he does, but it's a sliding scale, he said. "To the extent I'm really strict about it, my weight stays down. When I cheat, it creeps up - which to me is a pretty good indication that it's sensible."

This positive-feedback loop helps make a plan like VB6 easier to adopt. Plus, many people find eating mostly whole, plant-based foods and less salt, sugar and dairy turns up your taste buds.

When I asked whether his palate had changed, Bittman wouldn't go that far, "but my satiety levels are different. I can make a stir-fry with very little meat or fish and think it's great. I really have adapted to the 'meat as treat' thing. I don't like dairy nearly as much as I used to, except good cheese. The rest of it I could take or leave."

More this, less that

VB6 indicts the high-fat, high-processed, high-meat standard American diet as a junk habit we need to break, Bittman said in his email: "The science tells us we should be eating more vegetables and other unprocessed plant foods, and less of everything else. That is pretty much established. If you eat less junk and fewer animal products, and in place of those you eat plants, you're better off."

Bittman said he is presenting one strategy for doing that. "You can do it religiously, you can do it casually, or you can figure out another strategy: vegan except weekends, vegan after 9 a.m., vegan except Tuesday and Thursday - whatever. The idea is to shift the percentage of calories you get from unprocessed plants to as high a percentage as you can. Bearing in mind, again, that vegans eat junk food, too."

Fair enough. But couldn't similar results be achieved with an all-vegan plan that's unprocessed before 6, then pig out on vegan junk food after?

Sure, Bittman said.

A little bit pregnant?

So, if VB6 is good as far as it goes, why not go all the way? I was going to ask him, but Bittman had already answered that question in a blog post, "Why I'm Not a Vegan."

Some fans, he noted, had been grumbling, "Isn't being a part-time vegan like being a little bit pregnant?"

"Obviously not," he responded.

To him, vegan means plant-based eating, which one can start, stop and restart at will. As for the 1944 Donald Watson definition - completely forgoing animal use - Bittman's not ready to go zero-hog, waiting for "the emerging dominance of a morality that asserts that we have no right to 'exploit' our fellow animals for our own benefit," or other trends that would make "universal, full-time veganism" a good blanket recommendation.

"VB6 is about changing your diet," he told me. "It's permanent and it's huge. Ethics enters into it, of course . . . we should not be torturing animals or treating them like widgets."

And then there's the planet: "Animal production as it stands now is probably the biggest agricultural threat to the environment," he noted.

VB6's health-motivation strategy could help people address these other issues by changing to more positive habits. "I'm more focused on real food than on pure veganism," Bittman said. "Junk food, highly processed food - animal or not - is really the biggest problem in health."

And if people cut down their meat and dairy intake, who'll complain? He reminded me that "any strategy that reduces animal consumption is a good thing."

Very true. And the more people eating animal-free for whatever reason, the more menus will adapt. Which leaves vegans like me with less to grumble about.


A VB6 Day

Mark Bittman's new book, VB6, includes a 28-day, meal-by-meal plan to keep daily food choices fun, varied and nutritious. Here are some options, referencing recipes in the book:

BREAKFAST: Hot oatmeal; blueberry smoothie; homemade cold cereal with almond milk; or Scrambled Tofu With Tomatoes.

LUNCH: Chickpea Ratatouille and a salad; Creamed Mushrooms on Toast (see recipe); Now-or-Later Vegan Burgers on Daily Salad Bowl; or Vegetable Miso Soup With Squash and Tofu.

SNACK: Homemade Tortilla Crisps; Spiked Guacamole; Kale Chips Lacinato; Beet Candy; Tofu Jerky.

DINNER: Sweet Potato Frittata, with or without bacon; Fisherman's Stew; Hurry Curry With Brussels Sprouts, Red Peppers and Green Beans with D.I.Y. Crusty Bread; or Shrimp Tabouleh With Cooked Kale.

DESSERT: Frozen fruit or sorbet; sweetened yogurt; popcorn.

Have a question for Mark Bittman? Drop it in the comments section of this story and we'll run his answers early next week on The Conversation blog on PhillyDailyNews.com.

Vance Lehmkuhl is a cartoonist, writer, musician and 12-year vegan. "V for Veg" chronicles plant-based

eating in and around Philadelphia. VforVeg@phillynews.com or @V4Veg on Twitter.