Every year dozens of new diet books hit the shelves. In 2011, three new books aimed at helping you shed the pounds made it onto bestseller lists.

Those books: the Dukan Diet, the 17 Day Diet.. and The Spark.

The Dukan Diet made waves last year after Kate Middleton's mother reportedly used the diet to get into shape before the royal wedding.

Created by Dr. Pierre Dukan, it is split into 4 phases:Phase 1: Attack- 1 to 10 days of eating only meat and oat bran. Phase 2: Cruise- brings in veggies.. but no fruit. Phase 3: Consolidation- adds fruit and gives you one cheat meal a week.Phase 4: Stabilization.- six days a week of sensible eating, and one 'attack' day, eating only protein.

Ronni Litz Julien, a nutritionist, likes the way the diet uses oat bran. but she says other parts are tough to chew.

"It does talk about eating 100 foods as much as you want, but we don't really want to learn that, said Julien. "The focus is eating when your hungry and stopping when you're not."

The 17 Day Diet was created by Dr. Michael Moreno.

Books sales took off after he was featured on a few medical talk shows.

This diet also goes through different cycles, like the accelerate cycle, which involves eating less carbohydrates. The activate phase starts something called "carb cycling," which is said to reset your metabolism.

Julien tells Local 10 that is a myth.

The Spark is written by Chris Downie, who decided to take his hugely successful website SparkPeople.com and turn it into a book.

It's a diet plan similar to the USDA food pyramid.

Calorie restrictions are based on whether you choose a 'moderate' or 'aggressive' weight loss plan.

Of all the diets, this one was Ronni's favorite.

But if you are looking to take the weight off for good in 2012, she says you may want to put the books down, and try instead to make manageable food changes on your own terms.