Starvation mode a myth or not?

this is very dependent on what you refer to as 'starvation' - i'm a big advocate for fasted cardio first thing in the AM upon waking only on the premise that you have an adequate diet/nutritional plan. In reference to people 'starving' themselves to lose weight then you will in fact lose muscle before you lose fat, this can often result in what could be called, skinny fat, whereby you may have the image of a smaller frame though your overall body composition is in fact more fat than muscle, you will then find it harder to 'tone up' as you cant tone muscle that isnt there. I do feel there is a place for fasted cardio, fasted weight programs though it must equally be balanced with an adequate nutritional plan to accommodate and prevent your muscles going catabolic.