1. Get in balance.
Eat a diet that's 45 percent carbs, 30 percent protein, and 35 percent good-for-you fats—olive oil, fish, or nuts. "Eating too little fat makes you feel deprived," Forberg says. "Sprinkle almonds on your salad, put Parmesan cheese on your whole-wheat pasta, or slice avocado on your sandwich. Fat is a flavor carrier that helps other foods taste more robust."
2. Avoid anything artificial.
Stick with real foods, such as vegetables, fruits, nuts, lean meats, low-fat dairy, and whole-grain pasta, rice, and bread. "The idea is to get the biggest nutrient bang for the calorie buck. Processed foods contain a lot of junk. Real foods are antioxidant-rich and fiber-filled."
3. Pile on the green stuff.
"The bulk of your diet should be vegetables, such as tomatoes, mushrooms, zucchini, spinach, and other greens," says Forberg. Vegetables are high in fiber and water, which fill you up. "You'll be surprised by how much you can eat when you follow this plan."
4. Keep a food journal.
"People who write down what they eat after every meal lose twice the weight of those who don't."
5. Set healthy limits.
"On the show, we recommend women consume 1,200 to 1,500 calories a day and men 1,600 to 2,400, depending on their size," says Forberg. "If you're super-tired, eat a little more. This is about making a lifestyle change and doing something that's sustainable."
6. Never let yourself get famished—or too full.
"When you're super-hungry, you choose the wrong foods and eat too much. Stop when you're comfortably full. You should never have to unbutton your pants!"