AceShowbiz -

Everyone knows that Kim Kardashian is struggling to lose her weight after she gave birth to son Saint in December last year. The mother of two reportedly eats 1,800 calories a day to lose 28 pounds of her weight although she already managed to lose 42 pounds during the past three months.

Kim's Atkins nutritionist, Colette Heimowitz, opened up about what the "Keeping Up with the Kardashians" star did to lose her weight. She told Redbook that Kim went on a strict diet as she focused on eating proteins like eggs, chicken or meat and healthy fats while avoiding sugar.

"The secret is to pick high-fiber carbohydrates that slow the release of sugar into the bloodstream. Instead of white rice you have a little brown rice," Colette explained. "Instead of a white potato you could have a yam. And [when you want] dessert, you can make one with Splenda instead of sugar." She also said that Kim stayed away from "sugar, sweets, cakes, crackers, white flour, white rice."

Kim, who is a serious cheese lover, had to control her desire to eat the dairy product. "[Kim] is limited to four ounces of cheese a day," Colette said. "These things aren't unlimited, but she can have them - just enough to keep you satisfied."

Colette went on saying that the key to successful dieting was controlling your desire to eat. "A low-calorie diet leaves you hungry all the time, and you need to not be hungry in order to be successful," she said. "When you have adequate calories, protein, fat and high-fiber carbohydrates [in your diet], you won't be tempted to add something."