How do you calculate the calories needed to lose weight or dry yourself? 1 g protein = 4 calories 1 g carb = 4 calories 1 g fat = 9 calories Consider that you are 100 kilos Your need for calories will be 100 * 33 = 3300 calories daily For healthy weight reduction and drying, you should eat protein, complex carbohydrates and healthy fats. Your need for protein will be 100 x 3 = 300 grams protein per day To find out how many calories you'll get from protein, you multiply the result by 4