Finnish people drink a lot of coffee; in my place of work it's a mug (0.2 litres) every two hours or so during a twelve hour shift. Some people there have been doing that for over a decade and apparently their dosage and consumption interval has remained the same, keeping blood caffeine levels quite steady.
Same here, but I take that 0.2 litres every hour during a 9-10 hour workday.
I have noticed that if I don't get caffeine, I have a headache within a day. It lasts for about 3 days, or up to week. Then the cold turkey is over. I switched to green tea for 1.5 years when living in Asia (quite bad coffee, sorry) and then started again with coffee.
Decaffeinated is not popular here (e.g. our office does not have it) but Finnish coffee is no espresso so it's not that strong in caffeine. I prefer espresso beans though, not the light roast that is typical here.
> What happens when you develop a tolerance to caffeine after prolonged use? Study doesn't really explain that.
I've seen a couple of studies on the effects of coffee/caffeine on alertness. They showed that initial usage produced heightened alertness, but the body adapts relatively quickly, resulting in lower baseline alertness and a need to use caffeine to reach an alertness level roughly matching (or often not quite matching) the original pre-caffeine baseline.
So: you start drinking coffee, you get short-term alertness, long-term you have to keep drinking it to get back to the alertness you started with before you started drinking coffee.
When I develop a tolerance? Considering I can and sometimes do finish an entire pot after 10pm, especially if I'm going out on the weekend. Yet afterwards I can still shut my eyes and fall asleep within half an hour.
So your worries are well founded as drinking so much has given me the powers to turn Coffee into Water
That's what I was wondering about too. I remember reading that tolerance to caffeine, regarding alertness, develops very quickly - around 12 days. It would be most interesting to know if the same happens to the effect on memory and mood.
I'm sure many drugs / stimulants make you feel better in short term but what about the long term?