Anecdata, but an acquaintance of mine struggled with lifelong anorexia. Severe enough that he was hospitalized a few times. With great effort he could cling to the bottom of the "normal BMI" range, but his life was generally ruled by the eating disorder - he couldn't have meals with people, he had to do various exercise rituals.
He was an early participant in one of these psychedelic studies a few years ago. After the first treatment, he said he couldn't really tell if it had any effect. But six months later, he was totally changed - able to function almost normally.
We should exercise our usual amount of skepticism about miracle treatments, but my hope is that his experience can be replicated.