Yeah, notice how MyProAna take a delusional approach to weight loss?  They make it hard for themselves by "it has to be light foods and you have to feel hungry" rules--instead of feeling full so you aren't obsessed with food and don't overeat.  If you're an actual anorexic and your goal weight is a BMI of 15 or below, sure, soup cans and protein are too high-calorie for that, but if you're a fat wannarexic who wants to become human again, they're just going to binge later.