I have not noticed hairloss. I am not sure if some are more susceptible to it, but that may be a thing. I also know there are many who truly have 1 meal after breaking their fast. I don’t do this, I eat almost past being satiated. It is one of those things where my eyes are bigger than my stomach situation. But I typically go 60-85 hours between eating, so I really can’t do much damage, although I don’t always feel great after eating, lol.
Basically, even though there is a large deficit because max I typially eat for the week is 5000-6000, and that is upper limit territory. I feel eating all that food split in two days per week gives some assurance to my body versus taking those same weekly caloric amounts and breaking them into daily rations, say 750-850 calories daily doing OMAD.