Does caffeine really *work*?

As I’ve progressed through another night of what appears to be insomnia without sleeping I have to wonder, does caffeine really work for any of you?

I’m always hearing about people getting charged for the day with coffee, tea et cetera.

Well I’ve drank 3-4 cups of coffee in a single sitting, I’ve done 3+ cans of red bull et cetera when I REALLY need energy and it just doesn’t seem to work for me. Am I an exception? Does caffeine work but doesn’t help much against extreme exhaustion? Or maybe it is working it’s just the effects are overstated by the general public?

I think people have a variety of reactions to caffeine. Some people can have a couple of cups of coffee after dinner without affecting their sleep, some would be up all night. I’ve definitely gotten the shakes after drinking a pot of coffee, but I don’t particularly notice getting energized after my morning cup.

FTR, I would avoid caffeine after noon if you’re having trouble sleeping. No sense making it harder on yourself to sleep.

I’ve been there, done that!
At one time I drank a pot of coffee at midnight while studying.
Then one holiday season on Friday, school all day, worked midnight shift, slept and studied Saturday. Worked midnight shift, slept and studied Sunday. Worked midnight shift, school and no sleep Monday. Worked midnight shift Tuesday AM and was literally going to sleep stand up about 2 AM. Up to this point I had been drinking coffee in normal amount. At this point I downed a “No-Doz” (citrated caffeine) tablet which had not effect …for about 30 minutes. Suddenly it was as if a mule had kicked me and I was wide awake. school all day and another midnight shift w/No-Doz. Wed. no school so went home to fall into bed and get some fitful rest. Worked midnight shift through New Years. I’ve was hyper sensitized to caffeine for a long time afterwards. Even today no coffed after 4 or 5 PM
It seems to me that you are already saturated with caffeine. That would account for the insomnia and the failure of caffeine to ‘get you going’ in the morning.
Try avoiding any and all caffeine for a week and see if it doesn’t result in sleeping better.

It works up to your (or my) tollerence level and everyone’s reaction to it is different.

You might try Yerba Mate (tea like drink), which contains a compound simular to caffiene, but not exactly the same, IIRC called martiene.

Yes, it works. And it’s the devil.

Caffeine does absolutely nowt for me.

I can sup espresso by the gallon and there’s no effect, either physically or psychologically.

I felt the same way about caffeine…doesn’t affect me…until I went off of it. Now that I’m caffeine-free, I really notice the loss of it. I get drowsier in the afternoon, and sometimes it’s harder to get going in the morning. I think I’m definitely better off without it, because I’m reacting to my natural rhythms now, but there are days when I really miss that extra boost. And for the record, I never drank that much caffeine, because I don’t drink tea or coffee.

This month’s National Geographic’s cover story is about caffeine. I haven’t read it yet, but there might be answers in there as to why some people react differently.

You’re up night after night after drinking coffee and you want to know if caffeine “works”? :smack:

When caffeine works for me, I know I’m really tired. On a day to day basis, no, I can’t tell that it affects me. But after a red-eye transatlantic flight, when I’ve been up for 40 hours and then can only sleep for 4, suddenly, coffee does miracles.

It does take away some of my headaches.

MY SO goes to bed at night with a diet coke. She even has it on her nightstand. If I had a diet coke before I went to bed I’d be climbing the walls! The funny thing is that back home in Ireland everyone drinks tea before going to bed.

Just a little anecdote, I had insomnia last night myself and watched the Surreal life for hours on end :wally

I’ve known people who got sleepy from coffee. It’s not unlike (if not the same) as the effect on some people who calm down when taking Ritalin, which is actually a stimulant for most people.

So it would not be surprising if there are in-between people- for whom coffee has little effect.

Caffeine really does not work all that well when you are drinking a couple pots of coffee per day. There is never any reason to consume more than 300mg of caffeine over the course of an average day.

Low-dose repeated caffeine administration for circadian-phase-dependent performance degradation during extended wakefulness. (pubmed)

When you get into the higher dosage range, caffeine starts to impair performance. It’s hard to ignore the somatic effects of 5 cups of coffee in as many hours.

I was going to mention this months National Geographic article. It was a fantastic article, not only do they now have panty hose that has caffeine intertwined into the leggings, but they also give some startling facts about the drug. It is the most widely used psychoactive drug on the planet. And it does effect everyone who takes it in whatever form. However, the ways in which it effects us varies like the wind. Some people (like my father) can have a cup of Joe at 11 p.m. and promptly go to sleep and sleep soundly all night. Others have a cup of coffee at night to stay awake. the release of dopamine in everyones system varies widely and effects us all differently. Think of Child A who takes a ritalin and it calms her down, whereas Child B takes a ritalin and is bouncing off the walls. SO it does not surprise me at all that the OP has no effect from the caffeine, they are not alone.

Yeah, the effects vary widely from person to person. Me, I feel almost no “high” after drinking caffeine, but I do notice a significant “low” a while later, especially if I’ve been drinking a lot. I remember one time in my poorer days when the local store had 24-packs of Mt. Dew on sale for $2 each. I went for a week drinking a can every couple of hours. After three or four days, I was so tired I could barely keep my eyes open.

OTOH, a friend of mine at work starts bouncing off the walls whenever she has some. She doesn’t have to tell me - it’s blatantly obvious. It’s like she becomes a completely different (and more obnoxious) person.

How Caffeine Works.

I can tell you that on New Years Day I had a cherry coke at lunchtime. I was up until 2:00am because I couldn’t sleep. I normally try to avoid caffeine at all costs so when I have a little it hits me hard.

I should also add that I don’t feel like caffeine makes me any “less tired.” Instead, it just makes me less “sleepy.” In other words, I still feel tired, I just can’t sleep.


I find that caffeine doesn’t energise me very much. I feel much the same on days when I don’t have any caffeine as on the days I drink 7 or 8 cups of coffee. Most weekdays I drink at least 3 cups.

You may find that if you put sugar in your coffee (or consume sugar from any other sources) that you will be hit with an energy slump shortly afterwards. Sugar consumption causes a spike in your blood sugar levels which is quickly followed by a slump as insulin is mobilised to remove the extra glucose from your blood.

Everybody else is posting their anecdotes, why shouldn’t I…

I get my best results from caffeine when I drink it in moderation (one or two cups) and not too frequently (no more than 4 days a week). It gives me a real boost in mood and concentration after breakfast or lunch. Gets me productive, sets my toes to tapping, etc.

If I drink it after 2pm then I have problems sleeping. If I drink it more than 4 days a week, or more than 2 cups a day, then I start having problems with jitteriness, “crashing”, irritability, etc.

When you’re fatigued your body produces a chemical called adenosine. This travels around your system and binds to receptors nerves which respond by slowing down your bodily functions.

Caffeine is chemically similar to adenosine. It will bind to the same receptor nerves and block the adenosine from triggering those nerves. However caffeine does not produce the slow-down response that adenosine does. So essentially, you’re just as fatigued but the caffeine prevents your body from knowing it’s fatigued.

But it’s not nice to fool with Mother Nature. If the receptors are regularly blocked, your body responds by creating new receptor nerves. So the same amount of caffeine that used to block all your receptors and keep you from feeling tired is no longer enough. The adenosine in your body finds receptors to trigger and you feel tired normally even though you’re cranked on caffeine.

The good news is that if you reduce your caffeine intake, the receptors will decrease in the same manner as they increased. But basically, caffeine can only be a short term solution to avoiding fatigue.