I recognise what they are talking about here. Although technically I’m not sleep deprived I am usually extremely tired and the worse I am (the more I try to live normally) the hungrier I get. It’s absolutely an observable phenomenon – D will tell you. I’ve explained it thusly before “it’s like my body is trying to convince me that if I could just get enough/the right fuel in, I won’t be tired anymore”. It makes sticking to a healthy diet with CFS/ME extremely difficult.