Mary Aalborg-Volper in Cloverdale slowly lost 35 pounds on the 17 Day Diet by Dr. Mike Moreno, which cuts out sugar and limits carbohydrates for 17 days.

"Then you add things back and learn about portion control," she said, adding that the latter is the most challenging part of the diet.

Of course, with any diet there are as many doubters as believers.

Regarding the 5:2 diet, Santa Rosa dietician and teacher Jill Nussinow questions if "a diet of only 600 calories a day is appropriate. Most people need a minimum of 1,200 calories a day."

Nussinow, known as "the Veggie Queen," said when choosing a diet, "let it be something you can follow for your entire life. Make it a lifestyle, not as something to go on and then go off."

Avoid any plan, she said, that promises you can safely lose 5-10 pounds per week and lose weight only from certain parts of your body. And like most nutritionists, she approves of any diet that says "no" to processed food.

Nussinow used to teach the McDougall diet (no meat, lots of carbohydrates, little fat), which she endorses because "it allows a person to eat a lot of nutritious food," but she notes its high-carb content doesn't work for all.

As for the Paleo, she said, "The entire premise is wacky, but if people get good results and can maintain their health, good for them."

<i>Susan Swartz is a freelance writer and author based in Sonoma County.</i>