Your brain on -- and off -- caffeine

May 01, 2009
coffee

Ever miss your daily cup of coffee and subsequently get a pounding headache? According to reports from consumers of coffee and other caffeinated products, caffeine withdrawal is often characterized by a headache, fatigue, feeling less alert, less energetic and experiencing difficulty concentrating.

Researchers from the University of Vermont College of Medicine and Johns Hopkins School of Medicine sought to investigate the biological mechanisms of withdrawal in a paper published recently in the online edition of the scientific journal Psychopharmacology. They looked at brain and blood flow during caffeine withdrawal to examine what was taking place physiologically during acute caffeine abstinence, including the likely mechanism underlying the common "caffeine withdrawal headache."

The group examined caffeine's effects in a double-blind study, which involved the administration of caffeine and placebo capsules. Each participant's response to the caffeine or placebo was measured using three different measures — brain electrical activity via electroencephalogram (EEG); blood flow velocity in the brain via ultrasound; and participants' self-reports of subjective effects via questionnaires.

The team demonstrated that stopping daily produces changes in cerebral blood flow velocity and quantitative EEG that are likely related to the classic caffeine withdrawal symptoms of headache, drowsiness and decreased alertness. More specifically, acute caffeine abstinence increased brain blood flow, an effect that may account for commonly reported withdrawal headaches. Acute caffeine abstinence also produced changes in EEG (increased theta rhythm) that has previously been linked to the common withdrawal symptom of fatigue. Consistent with this, volunteers reported increases in measures of "tired," "fatigue," "sluggish" and "weary." Overall, these findings provide the most rigorous demonstration to date of physiological effects of caffeine withdrawal.

The researchers also discovered a provocative and somewhat unexpected finding — that there were no net benefits associated with chronic caffeine administration.

"In addition to looking at caffeine withdrawal, this rigorous design also permitted comparison of chronic caffeine maintenance with chronic placebo maintenance, which provides unique information about the extent to which there are net beneficial effects of daily caffeine administration," said Stacey Sigmon, Ph.D., research associate professor of psychiatry at the University of Vermont and first author on the study. "In contrast to what most of us coffee lovers would think, our study showed no difference between when the participant was maintained on chronic placebo and when the participant was stabilized on chronic caffeine administration. What this means is that consuming caffeine regularly does not appear to produce any net beneficial effects, based on the measures we examined."

Source: University of Vermont

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User comments : 9

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deatopmg
1 / 5 (1) May 01, 2009
"What this means is that consuming caffeine regularly does not appear to produce any net beneficial effects, based on the measures we examined." COFFEE IS NOT PURE CAFFEINE!

This study used pure caffeine NOT coffee!! In the early 80's several potent opioids were discovered in coffee. At the time it was proposed that the withdrawal symptoms that coffee drinkers experienced on abstinence was due to opioid addiction. Obviously these researchers did not do a very good literature search.
daqman
not rated yet May 01, 2009
I once did the experiment. I found some OTC product (a diuretic I think) that was basically caffeine. I stopped drinking coffee and took the equivalent amount of caffeine with water. Ok, it's a sample of one but what I found was it was the coffee I crave not the caffeine. Strangely though decaf doesn't work for me even if I don't know it's decaf (getting my wife to make the drink and not tell me). So, either something else (other than caffeine) is lost in the decaf or there is something in coffee that enhances the effect of the caffeine.
bmcghie
not rated yet May 02, 2009
As a pretty hardcore coffee drinker (homemade americanos, lattes, and mochas) I would have to say I very rarely drink the coffee for the "caffeine boost." I drink coffee because I enjoy the flavor, and I find it relaxing to sit down with a warm cup of something. Tea is good too, but doesn't fill you up as much as a latte (whole milk is SO good).

I think most of us are aware that caffeine/coffee doesn't give a chronic beneficial effect. We drink it because we enjoy it, and unfortunately in some cases because quite a few of us have become habituated to getting the morning buzz, real or illusory.

^ dagman, have you tried different versions of decaf coffee? Supercritical CO2 extraction is commonly used, but also takes out other compounds and is probably why you end up unsatisfied. The Swiss Water Process is a little different, and is generally considered to make a better cup of decaf, but is much more expensive. The most expensive method uses organic solvents, but is generally discontinued because of contamination incidents in the past. Apparently it did the best job of ONLY taking out the caffeine, but quite often all of the solvent was not rinsed from the beans.

Bottom line? I'd say drink the damned coffee when you want to, enjoy it, and make sure you get your 8 hours every night so you don't think you need it to function in the morning.
superhuman
not rated yet May 02, 2009
This study used pure caffeine NOT coffee!! In the early 80's several potent opioids were discovered in coffee. At the time it was proposed that the withdrawal symptoms that coffee drinkers experienced on abstinence was due to opioid addiction. Obviously these researchers did not do a very good literature search.

Both effects and withdrawal symptoms of coffee have nothing in common with those of opioids.
Suzu
2 / 5 (1) May 02, 2009
I was heavy drinker of coffee, but decided to stop because I kept getting weird dizziness and a NEED to drink more of it, plus the pee smelled strongly after drinking coffee, which for some reason was a huge turn off.

Anyways quitting drinking coffee was worse than stopping smoking. Withdrawal was horrific, my head constantly hurt for 2 weeks straight after I stopped drinking coffee. Only reason I didn't resume drinking it again is because I was disgusted with how addictive coffee is to force me to have such a pita withdrawal and I was stubborn.
Roj
not rated yet May 02, 2009
Profit is maximized by packaging the low-cost Robusta variety of coffee beans, which have more caffeine, relative to high-cost Arabica varieties.

Unless roasting your own, even StarBucks consumers are lucky to taste an Arabica coffee bean (ie) Kona, much less a fresh roast less than two weeks old, according to professional roasters.

Further, the most common type of American drip brewing will extract more caffeine, relative to expresso (steam blasting) methods.

Anyone who loves coffee can avoid a great deal of caffeine by ordering Arabica varieties of beans or roast, and avoid drip brewing, or using the same grinds twice in expresso machines.

Since, I like my coffee black, a hyper sensitivity to caffeine (irritability) still requires the antidote; a cup of milk taken just before the coffee.

Perhaps not an antidote for everyone; neither is the temperature-controlled draft / craft beer everyone's after-work celebration (German: fireabend) A cultural antidote.
Shootist
5 / 5 (3) May 02, 2009

"Anyone who loves coffee can avoid a great deal of caffeine by ordering Arabica varieties of beans or roast, and avoid drip brewing, or using the same grinds twice in expresso machines."

The best coffee I ever had; my grandfather boiled his coffee on the stove, served it, still boiling, and drank it from the saucer.

Avoiding caffeine in coffee is like avoiding fat in yogurt or alcohol in beer. Why tamper with that which is already perfect?
BarrySpencer
5 / 5 (1) May 02, 2009
The article doesn't mention adenosine. Caffeine works by blocking adenosine receptors located on the surfaces of neurons. The nervous system adapts to caffeine, so that caffeine users can function fairly normally despite the interfering presence of caffeine. It is this adaptation that causes the nervous system to malfunction when caffeine is withdrawn.

The author wrote: "...acute caffeine abstinence increased brain blood flow, an effect that may account for commonly reported withdrawal headaches."

That's incorrect. Vascular dilation in the head is a symptom of caffeine withdrawal, not the cause of headache or other caffeine withdrawal symptoms.

The underlying cause of both the vascular dilation and the headache associated with caffeine withdrawal is adenosine. During caffeine withdrawal the concentration of adenosine in the head is elevated above normal. Adenosine is a potent vasodilator; adenosine applied to the skin, for example, causes localized pain and vasodilation.

Astoundingly, primary headaches such as migraine and tension-type headache have never been demonstrated to occur absent caffeine use/caffeine withdrawal. Which means it may be primary headache doesn't occur absent caffeine withdrawal. In other words: it may be migraine IS caffeine withdrawal headache.

That possibility isn't as far-fetched as it might seem. We know caffeine withdrawal can cause severe headaches indistinguishable from migraine. And caffeine use is commonplace enough to account for the high prevalence of migraine and other primary headaches. Also: administered caffeine often relieves migraine. Add those facts up and caffeine emerges as the most likely culprit behind migraine and the less-severe headaches called tension-type headaches.



Mauricio
not rated yet May 03, 2009
Caffeine binds to adenosine receptors. So when there is no caffeine, the receptors receive a high level of activation from adenosine. It seems that caffeine blocks the receptor for adenosine, it does not produce activation of it, whereas when adenosine is present, it activates the receptor and induces sleepiness.