how to calculate protein needs for underweight people
1 Body Fat Calculator. 2  Though not as accurate as using calibers, this is a quick and easy estimate of your percent body fat. 3  Nutritional Calculator. 4  This calculator will determine your calories, protein, fat, and carbohydrate needs in relationship to weight loss, maintenance or weight gain. Nutritional Calculator. 2  This calculator will determine your calories, protein, fat, and carbohydrate needs in relationship to weight loss, maintenance or weight gain. 3  Food Planning Calculator. 4  This calculator was developed to use food groups to meet your nutritional needs.