losing muscle mass = losing weight What you are defending is fitness, what we are discussing is weight loss If you are 580 pounds heavy, restricting the numbe

losing muscle mass = losing weight What you are defending is fitness, what we are discussing is weight loss If you are 580 pounds heavy, restricting the number of calories you consume is far more important than making sure x% of your calories are from fats/carbs/proteins. The only bearing food choice has on this matter is how full you will feel, and that is matter of personal preference and a small bit of choosing more protein rich foods, but if you don't mind feeling hungry you can lose weight just as well on 3 snickers bars as 3 chicken breasts with rice. see http://www.boredpanda.com/what-200-calories-look-like/ http://www.boredpanda.com/what-200-calories-look-like/ for a visualization of how healthier foods will make you feel more full. for example, 200 calories of M&Ms is 40 grams, the same number of calories from apples is 385 grams - almost 10 times as much physical stuff occupying your stomach