A couple who went on Mount Sinai's South Beach Diet last year has about 100 pounds of evidence to prove that the diet works.

Karen Leibowitz, who lost 40 pounds, has a closet full of clothes that don't fit. She used to wear sizes 14 and 16. Now she wears a size 8.

Leibowitz's husband, Burt, said that the diet helped him drop from a size 44 to sizes 38 or 40. He lost 52 pounds.

"I was pleasantly surprised, because over a number of years, I'd been on so many different diets," Burt said. "I would lose the weight, but then I'd cheat and get right back to my former weight and even go heavier."

But Mount Sinai's South Beach Diet was different. The Leibowitzes said that the food was good. They also said that because there are plenty of choices, they ate a variety of food, and the pounds fell off.

"The fact that you don't get hungry on the diet made all the difference in the world," Karen said. "And you didn't have to count portions or calories. There are just certain foods you could eat and certain foods you couldn't."

The Leibowitzes couldn't eat carbohydrates like white potatoes, white rice, enriched bread and pasta. But they could eat huge portions of low-fat proteins like chicken, fish and steak. Also, lots of fiber-rich vegetables are encouraged. And later, the Leibowitzes added brown rice, whole-wheat bread and sweet potatoes to the menu.

The diet's founders claim that by eliminating starches and sugars, you can stabilize blood sugar levels. Burt said that staying away from sugar made a big difference.

"And you don't get the cravings for the carbohydrates, so you don't get hungry at night and you don't raid the refrigerator," Burt said. "You can stay on the diet because you feel satisfied and you feel full."

It took the Leibowitzes nine months to lose the weight. And today, they continue to eat many of the things that they learned about on Mount Sinai's South Beach Diet. Instead of eating baked potatoes, they have sweet potatoes. And when they order sushi, they get it with brown rice. For the Leibowitzs, the diet has become a way of life and a way to look and feel better.

"We will treat ourselves to no-sugar-added ice cream ? We don't feel like we're missing anything," Karen said. "You know, we feel so much better and feel we look better so we're willing to change our lifestyle."

You'll have a chance to talk to the diet experts Thursday. The doctor who created the diet will be on "Daybreak" starting at 5:30 a.m. Also, our live phone bank starts Thursday night at 5.

Click10 is making your Mount Sinai's South Beach Diet experience interactive. Get your questions about the diet answered by Kristi Krueger on Monday nights from 6:30 to 8. Click here to join the discussion and see what questions she has already answered.