Originally Posted by
Amethyst Star
I'm more of a sweeter-coffee-drink person when I'm getting something fancy, but I'll drink everything from drip coffee to americanos to mochas to blended drinks.
Caffeine affects people in different ways. I've found that personally, I have a burst of energy about 10 or 15 minutes after I start drinking the coffee, but then about 7 or 8 hours later, I get another boost of energy. I'm not sure if it's a "crash recovery", but nonetheless there it is. That's why I try not to let myself drink much with caffeine after about 2 or 3pm. As for affecting your REM, it just depends on how you're affected by coffee. I don't think it'd affect your REM persay, but it could give you a rough time falling asleep and frustration sometimes causes you to sleep lighter. For me that means average dreams.
I gave up coffee for 40 days and it wasn't as hard as I thought. Granted I was drinking about 2-4 shots per day, not as much as you (depending on how big your cups are), but I've also been blessed in that I don't usually get really grumpy or suffer from headaches if I go without caffeine. Again, it just affects people differently.
Sometimes I just like to give my stomach a break from all the crap I throw down into it, so I'll take a day off of coffee... like today. Which in hindsight, with only 3 hours of sleep may not have been the best idea.