Well metabolic damage is very real imo. As is the ability to speed up your metabolism through feeding. Just because you may not have noticed it I think it's well documented. Some people go very low calorie and high expenditure and hold onto weight as their bodies go into starvation mode. Whilst it can be relatively easy to get back from that there can be long term damage for some people.
elvia, can you expand on this (metabolic damage) in your experience? for the longest time i was so scared of "damaging my metabolism" by hard dieting on very low calories, but over the years I've done crazy diet/training regimens, (such as psmf diets while training (hard) 7 days a week along with working an extremely physical job for 8-10 weeks at a time and I've just never seen the "metabolic damage" that some people speak of. I've observed the same thing with a number of guys who I train with.
I know I'm just one guy, an everybody is different, but I just don't think it's that easy for someone who isn't super lean to really damage their metabolism, as they still have plenty of bodyfat to feed off of.
Yes, if someone is extremely lean and is doing a huge workload of training/cardio, and on extremely low calories for extended periods of time throughout the year, year after year, yes, I can see some possible metabolic damage happening, but outside of that, I'm skeptical..
Curious as to your thoughts and experiences on why you think metabolic damage is a very real thing?