EVERY MORNING, subscribers to the Hungry Girl newsletter receive a peppy e-mail full of low-calorie eating tips in which "Chew the Right Thing" is a regular feature, "OMG" is a favorite expression and "two yums up" is the ultimate product endorsement. Each e-mail - chatty, informal and packed with capital letters and exclamation points - sounds like it was written for a friend.

But Lisa Lillien, known to her occasionally fanatic readers as Hungry Girl, has a lot of friends: over 735,000.

"I'm a very casual person," Lillien said. "The voice of Hungry Girl is basically me."

She recently released "200 Under 200" - that's 200 recipes under 200 calories each - the follow-up to her 2008 bestseller.

Lillien's enthusiasm in her e-mails is genuine: She said she enjoys prowling the aisles of supermarkets to hunt for new featured foods. She hardly needs to. Each week, she receives 20 to 30 boxes full of products from companies hoping that she'll give them a write-up and send her subscribers - whom Lillien calls "a powerful group" - rushing to the store to follow Hungry Girl's trusted advice.

In the past, subscribers have successfully lobbied Almond Breeze to create a new product and Trader Joe's to recall a snack with incorrect nutritional information. House Foods, makers of the low-calorie tofu noodles that, Lillien wrote, "WILL change your life," now proudly sports a "Hungry Girl-approved" logo on its packaging.

Back in 2002, Lillien did not yet have an army of calorie-counters she could mobilize with a single sentence, but she did have an idea.

Some have perpetuated a storybook narrative of a random, diet-conscious woman whose e-mail to 75 friends became a surprise hit, but the phenomenal success of Hungry Girl was no happy accident. Lillien, formerly a vice president of new media at Warner Brothers, recognized what she saw as a void left by mainstream nutritional advice, and she jumped at the opportunity.

"Most of the information about eating better is brought by nutritionists or dieticians, and it's not fun [or] realistic and relatable," Lillien said. "I wanted to create a brand in this space that would address every woman's needs."

At first, five new people would subscribe each day, then 10, then 100. Now, Lillien estimated, between 700 and 1,200 new people sign up for Hungry Girl every day.

As Lillien is the first to admit, she is neither a chef nor a nutritionist. Instead, she attributes Hungry Girl's explosive growth to what she claims is her secret weapon: "I think I have universal taste buds," she explained.

"I can taste something and say, 'Everybody is going to love this,' or I can taste something and say, 'I like this, but only 20 percent of people will like this.' "

Lillien spends day after day in the Hungry Girl test kitchen with her nine-person staff, trying out recipes and sampling new foods.

She does accept money from advertisers and frequently endorses specific brand products but insists that she only recommends foods that fit her criteria: "Does it taste good? What's the nutritional profile? Do you get a lot of bang for your calorie buck?"

Lillien does not seem concerned by her promotion of calorie consciousness.

"I think it's great to be calorie conscious," she said. "People shouldn't be obsessed with it, but they should be aware of how many calories they're eating."

However, nutrition professionals don't necessarily think that hundreds of thousands of people should base their dietary plans on the advice of someone with no formal training.

Elizabeth Emery, a registered dietician and assistant professor of nutrition at the LaSalle University School of Nursing and Health Sciences, recently spent some time on Hungry Girl's Web site and said she was not impressed.

"Giving the message that as long as you control your calories you'll be OK ignores basic nutritional needs," she said. "Being thin is not the same as being healthy."

Emery also bemoaned Lillien's emphasis on processed foods, pointing to a Hungry Girl recipe for a banana smoothie with diet hot chocolate mix.

"What's wrong with bananas and milk or yogurt?" Emery asked. "Why do you have to add the diet hot chocolate mix? I wish that she would offer more tips on cooking without having to have something processed in everything she ate."

Lillien brushes aside such criticism, explaining that she offers a more realistic alternative for ordinary people who are trying to eat healthier.

"There are always going to be the purists who don't believe in any packaged food," Lillian said , "but people are going to eat packaged foods anyway, and they need help."

She mentions occasionally on Hungry Girl that she herself often will snack on an apple rather than a packaged bar, for example. But Lillien said she thinks that's too much of a leap for people who have eaten processed foods all their life.

"Someone needs to be the bridge between the complete 'shop the perimeter of the store' people and the full-on 'I'm eating a giant package of Oreos every day' people," Lillien said. "There's got to be a happy medium."

Lillien's massive and growing base of subscribers every day tells her that she's doing something right.

"People will come up to me and start to cry and hug me," Lillien said. "They say they feel like I'm their friend because I e-mail them every day." *

Lisa Lillien will talk about her new cookbook, "200 Under 200," at Wegman's, 2100 Route 70 West, Cherry Hill, at 6 p.m. tomorrow. For more information, go to www.hungry-girl.com.