"Dukan Diet" Causing Buzz after Kate Middleton, J-Lo Slim Down

Her Royal Highness Catherine Duchess of Cambridge slimmed down so much before the Royal Wedding, she had to get her ring refitted.

Her secret to dropping the pounds? Reportedly, the Dukan diet, with results many envy.

The diet--also linked to celebs like Penelope Cruz and Jennifer Lopez--is a low-fat, high-protein regimen, often compared to Atkins. “It’s not necessarily new. It’s just kind of the same thing, just repacked in a different way,” said Lisa Cimperman, a dietician with University Hospitals.

The Dukan diet is split into four phases.

First, the attack phase: you eat nothing but lean protein, a little oat bran and lots of water.

Second, the cruise phase: you stick with lean protein, add more oat bran and mix in non-starchy vegetables every other day.

Third, the consolidation phase, you get to add two slices of bread, an apple and a slice of cheese. You also get two "celebratory meals" in which you can mostly eat what you want.

And fourth, the stabilization phase, where you can eat a number of foods-even fried chicken and mac ‘n cheese.

Plans like Dukan can offer quick results, but dieticians argue they can come with a number of risks.

“It could potentially lead to diabetes later in life or even hyperlipidemia. Some of those diets do not meet the recommendations of the American Heart Association. They’re higher in fat, they’re higher in protein. They promote weight loss. But that’s also something that we’re striving to avoid in terms of heart disease,” said Elizabeth Pash, Manager of Nutrition Therapy at Cleveland Clinic.

Dietician Cimperman says the South Beach diet is a better option for a low-carb, high protein diet. She says it focuses on eating good carbs and good fats.

But as you know,  always check with your doctor before starting any weight loss program.