The Skinny on No-Carb Diets

Princess-to-be Kate Middleton's mother, Carole, prepared for Kate's royal wedding with the high-protein, low-carbohydrate Dukan Diet. Created by nutritionist Pierre Dukan, the strict regimen consists of four stages during which followers eliminate all carbohydrates, then slowly phase healthy starches back into their diet. Carole allegedly lost 4 pounds in the first four days of the diet; though it showed swift results, carb-cutting diets like the Dukan Diet can lead to a number of health problems, including kidney failure, high cholesterol, osteoporosis, kidney stones, cancer and a malfunctioning metabolism. Drastically restricting carbohydrates can also send the body into an altered metabolic state called ketosis, which changes the body from a carbohydrate-burning engine to a fat-burning engine.

"It's absolutely OK to want to look great for an event," Dr. Travis says. "But there's a healthy and an unhealthy way to do it."

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