I heard someone that i should eat protein for losing weight . but some said i should eat starches instead of protein...which is correct?

Complex: The answer is really both. Weight loss diets by design have less calories than you need to maintain your current weight but as you lose weight your body and metabolism adjust to slow down weight loss. Lean protein helps maintain muscle mass during weight loss but complex carbohydrates are important for proper hormone functioning therefore both have a role in healthy weight loss.

Protein: There are 2 goals. First - your calories IN have to be less than your calories OUT. Even if the calorie is super healthy, if it's a calorie your body doesn't need it will store it as fat. Second, you want to keep you blood sugar levels relatively stable. So eating plenty of complex carbs along with protein and fiber is your best bet.

Less calories: To lose weight, eat less calories than you need in a day. You should eat enough protein to prevent muscle breakdown. The starches you eat, you need the energy for the body to run. You also need at least a teaspoon of healthy oils a day to prevent a fatty acid deficiency and to help absorb vitamins A, D, E and K. A nutrition professional can help you determine how much starch and protein you need.