My smart watch measures the time I am in different stages of sleep. Over the last 3 days, my REM sleep has been about 3%, and normal is 15-25%. I read on Wikipedia that some anti-depressants suppress REMS sleep. I don’t think we have knowledge enough yet to say what this information means to my health. I do feel really bad when I first awaken every day, and on my weekends I like to sleep 12 hours.
I believe REM sleep is where you get most of your recharge. I have only hit REM a few times in 20 years. I have a brain injury, and that seems to affect me quite markedly