Scary thought: Going cold turkey with coffee has had very similar effects on me (after 2 weeks of 1-2 cups a day; 2-4 shots/day).
I've also had a similar feeling of deadness when I stopped eating meat, dairy and anything with additives for 6 weeks. The first week or so I was completely useless - this could have also been due to me trying to feel my way through to a balanced diet.
So much of what we consume ends up having all sorts of unknown effects on us and the minute we stop consuming them we really feel it - it's easier to never stop.
One bonus of cutting certain stimulants out of my life has been that I've ended up feeling much better.
The last time I got rid of coffee (back on it now), I switched to a high caffein tea and then steadily walked my way to low / no caffein teas. It is really, really hard to get going with cold drinks in a ND / MN winter.
I'd add, cinnamon naturally "perks" one up for the most part. I used to add cinnamon to my coffee (to avoid sugar), but works as well for tea, or your hot water, lemon and honey for a non-caffeinated morning (or afternoon slog) beverage.
I went cold turkey from all caffeine. One day, almost 10 months ago I said enough is enough and quit. While on caffeine I was always highly irritated, and was snappy with people. I just couldn't get enough caffeine to feel good, and was always tired.
When I went off I was dead to the world for about 2 - 3 weeks. I had a splitting headache which no medicine seemed to fix, and felt laggy. But after those 3 weeks I started to feel better. I had more energy, I was a lot less irritated and was happier in general. I was able to contain angry outbursts and in general have changed entirely. I have more energy now than when I was binging caffeine. I can stay awake longer, fall asleep faster, and I feel refreshed when I do get at least 6 hours of sleep.
Not drinking any soda has also helped in other ways. I no longer have a real need for sugar throughout the day and don't have nearly the same headaches I used to get from not getting my sugar fix. Since I have also lost a major source of calorie intake I have started to lose weight.
I don't drink anything with HFCS in it, soda's with natural sugars every so often (maybe once or twice a month), but mostly I drink water. I drink a glass or two of milk a day as well. One thing I have noticed is that living in America is that soda is pushed with every single meal. It doesn't matter where you go, what soda would you like with that.
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Since you mentioned no longer eating meat ... I have recently started eating a lot less meat, and even in the past week have stopped eating meat altogether, and I have yet to feel a real difference. It does make it a lot harder to think of meals to make though as I have been eating meat my entire life and it is an integral part of any meal my family used to make. Will see what happens in a couple of weeks from now :-)
"When I went off I was dead to the world for about 2 - 3 weeks.... Not drinking any soda has also helped in other ways. I no longer have a real need for sugar..."
You may be misattributing. Caffeine withdrawal is a matter of days [1]. 5 tops and I'm usually done in 2 or 3. (I've dropped cold turkey three times now, and each time I've personally experienced a marked decrease in my ability to function, but I've got various other possibly mitigating circumstances. I'm planning on trying again with my latest set of circumstances to see if it helps any as soon as my infant is no longer an infant.) Dropping that much sugar out of your diet can definitely take substantial time to acclimate to. (But it's a great thing to acclimate to.) You sound a lot more like someone who has gone through adjustment to a much lower carb lifestyle than someone who has gone off caffeine.
I went from drinking four liters of mountain dew, 6 cups of coffee and taking 500 mg No-Doze caffeine pills to nothing.
It is possible that lower carb may have had something to do with it. One thing I did notice though is that in compensation I was eating a LOT more candy at first. I'd eat gummi worms and haribo gummi bears by the kilo. The local gas station started giving me discounts on swedish fish! Luckily I eased off that after about a month, and now I eat very little to almost no candy.
One thing I would note is that it has changed how I taste sugar. A lot of sugary drinks such as juice (even natural sugars) will quickly taste too sweet. I also find it harder to eat candy because it just has this disgustingly sweet taste to it. The other thing is that with drinking water with my meals instead of soda I am finding that a lot of foods are over salted, and could do with half the salt and still taste just as great. My personal believe is that people want taste even after making their taste buds taste something really sweet like soda.
I've also had a similar feeling of deadness when I stopped eating meat, dairy and anything with additives for 6 weeks. The first week or so I was completely useless - this could have also been due to me trying to feel my way through to a balanced diet.
So much of what we consume ends up having all sorts of unknown effects on us and the minute we stop consuming them we really feel it - it's easier to never stop.
One bonus of cutting certain stimulants out of my life has been that I've ended up feeling much better.