Caffeine and its benefits in a moderate consumptionCaffeine and its benefits in a moderate consumption
Fabricia Nascimento GraçaFabricia Nascimento Graça
Slurped in black coffee orSlurped in black coffee or
sipped in green tea, gulpedsipped in green tea, gulped
down in a soda or knocked backdown in a soda or knocked back
in a headache pill.in a headache pill.

CocaCoca PlantPlant
LeafLeaf

It's hardly a coincidence that coffee and tea caught on inIt's hardly a coincidence that coffee and tea caught on in
Europe just as the first factories were ushering in the industrialEurope just as the first factories were ushering in the industrial
revolution. The widespread use of caffeinated drinks facilitatedrevolution. The widespread use of caffeinated drinks facilitated
the great transformation of human economic endeavor fromthe great transformation of human economic endeavor from
the farm to the factory. Boiling water to make coffee or teathe farm to the factory. Boiling water to make coffee or tea
helped decrease the incidence of disease among workers inhelped decrease the incidence of disease among workers in
crowded cities. And the caffeine in their systems kept themcrowded cities. And the caffeine in their systems kept them
from falling asleep over the machinery. In a sense, caffeine isfrom falling asleep over the machinery. In a sense, caffeine is
the drug that made the modern world possible. And the morethe drug that made the modern world possible. And the more
modern our world gets, the more we seem to need it. Withoutmodern our world gets, the more we seem to need it. Without
that useful jolt of coffee—or Diet Coke or Red Bull—to get usthat useful jolt of coffee—or Diet Coke or Red Bull—to get us
out of bed and back to work, the 24-hour society of theout of bed and back to work, the 24-hour society of the
developed world couldn't exist.developed world couldn't exist.
Caffeine the motor of modern society ?Caffeine the motor of modern society ?

Caffeine content inCaffeine content in
BeveragesBeverages

Tea (150 ml)
Black tea 40
Green tea 40
Decaffeinated black
tea
4
Iced tea, ready to
drink
30
Iced tea mix, unsweetened
13
Beverage Caffeine
content per
serving
(milligrams)
CaffeineCaffeine contentcontent inin
TeaTea

ModerateModerate consuptionconsuption

Two mugs of coffee or a mug of coffee and aTwo mugs of coffee or a mug of coffee and a
couple of Cokes during thecouple of Cokes during the dayday are all you needare all you need
to get you there. Itto get you there. It’’s considered as a moderates considered as a moderate
amount.amount.
RecreationallyRecreationally, caffeine is used to provide a "boost of, caffeine is used to provide a "boost of
energy" or a feeling of heightened alertness. It's often usedenergy" or a feeling of heightened alertness. It's often used
to stay awake longerto stay awake longer
40 min to absorb
after oral intake
Desire
for caffeine
12 hours to
eliminate
from the body
Excitment
readyness
Energy and
Adrenaline

ToleranceTolerance andand
SensitivitySensitivity

The addiction ? Taste or
Buzz?
Half of all American adultsHalf of all American adults
consume more than 300 mg ofconsume more than 300 mg of
caffeine per day.caffeine per day.

Caffeinne MoleculeCaffeinne Molecule
Caffeine blocks the hypnotic effect of adenosine andCaffeine blocks the hypnotic effect of adenosine and
keeps us from falling asleep. Caffeine has also beenkeeps us from falling asleep. Caffeine has also been
shown to enhance mood and increase alertness inshown to enhance mood and increase alertness in
moderate amountsmoderate amounts.
GuaranineGuaranine

Caffeine works in two ways :
- it blocks the Enzyme phosphodiesterase from removing the
secondary messenger cAMP, so the excitory signals from
adrenaline etc. persist much longer (recall that viagra works in
a similar manner)
- it blocks Adenosine receptors in the brain. Adenosine builds
up in the course of a day, and when levels are high enough,
the adenosine binds to receptors that cause nerves to release
inhibitory signals that lead to drowsyness and sleep.
Adenosine also causes a dilation of blood vessels to the
brain , presumably to provide more oxygen and nutrients to
-Adenosine-Adenosine
-Protein-Protein
spacefillspacefill
-Protein ribbons-Protein ribbons

The BonesThe Bones

Do not affect HeartDo not affect Heart

Caffeine is widely consumed throughout the world in behaviorally active doses.
Most of the data suggest that caffeine, in the doses that are commonly
consumed, acts primarily by blocking adenosine A1
and A2A
receptors. Caffeine
has a unique mechanism of action among all centrally stimulating drugs. It does
interact with the dopaminergic transmission, but the mechanism is very different
from that of other drugs such as cocaine and amphetamine. Caffeine does not
markedly increase the release of dopamine, and it does not lead to any
substantial increase in activation of D1
dopaminergic neurotransmission in
nucleus accumbens, in contrast to the other central stimulants. Instead it
increases transmission via cells equipped with dopamine D2
receptors in this
nucleus as well as elsewhere in the basal ganglia. The effect of caffeine in
nucleus accumbens is manifested as a decrease in activity of the cells involved,
whereas the effects of cocaine and amphetamine are associated with an
increased activity of the relevant cellular targets. Accordingly, the overall activity
of the nucleus accumbens is much less affected by caffeine than by cocaine,
nicotine, and amphetamine. Furthermore, the cells activated by cocaine possess
particularly dopamine D1
receptors, whereas those affected by caffeine possess
D2
and adenosine A2A
receptors. There is, however, very good evidence that D1
and D2
receptor-stimulating drugs interact and potentiate each other's actions.
Thus, the unique molecular and cellular actions of caffeine in the brain do not a
priori rule out a potential as an addictive drug, they only indicate that its
stimulant effects are different from those exerted by drugs such as cocaine and
Not anNot an addictiveaddictive
drug!drug!

Although there is a public perceptionAlthough there is a public perception
(especially in the US) that caffeine is(especially in the US) that caffeine is
detrimental to one's health, this has adetrimental to one's health, this has a
surprisinglysurprisingly weak basis in realityweak basis in reality..
One important aspect of caffeine use is that the margin for dose increases may be
limited by the biphasic effects of the drug. Reinforcement is observed with doses
even below 1 mg/kg, and doses above 10 to 15 mg/kg are usually aversive.
Similarly, doses that are behaviorally stimulant (increasing motor behavior) are
below about 30 mg/kg, and doses above 50 mg/kg are generally depressant in
these paradigms. Caffeine has important effects on alertness, and there is no
doubt that caffeine is widely consumed by subjects who need to stay awake.
Caffeine also has some poorly investigated analgesic actions that contribute to its
use. In some contexts there are performance-enhancing actions.
Tolerance develops to some caffeine effects but not to others. A complete effect
reversal, by contrast, tolerance to discriminative stimulant effects, motor stimulant
effects, and alerting actions develops more slowly and to a variable extent.
From the above considerations it is clear that caffeine cannot really be considered
a "model drug of dependence" (Holtzman, 1990). Its weak reinforcing properties are
due to a unique and atypical mechanism of action. The drug is self-limiting and
subjects do not gradually increase the dose, because tolerance development to
both the reinforcing and aversive effects is limited. There are few negative
consequences of caffeine use in moderation and the withdrawal affects are modest
and transient in the individuals that experience them. Caffeine will not be
designated a drug of dependence, it is different from drugs such as amphetamine,
morphine, ethanol, or nicotine, it is possible that, some quantitative criteria of

Fig. 1. Effect of caffeine on different
biochemical targets in relation to its levels in
humans. Note that caffeine is able to
significantly block adenosine effects on A2A
(most potent) and A1
receptors already at
the low concentrations achieved after a
single cup of coffee. To inhibit cyclic
nucleotide breakdown via inhibition of
phosphodiesterase, 20 times higher
concentrations are required; to block
GABAA
receptors, 40 times higher
concentrations; and to mobilize intracellular
calcium depots, concentrations of 100 times
higher are needed. These latter levels are
unlikely to be reached in humans by any
form of normal use of caffeine-containing
beverages (modified from Fredholm, 1980).
Caffeine do not harm if it isCaffeine do not harm if it is
consumed moderatelyconsumed moderately

GG uarana is found in many sodas, energyuarana is found in many sodas, energy
drinks, protein bars, and natural weight-lossdrinks, protein bars, and natural weight-loss
aids. It comes from the seeds of a woody vineaids. It comes from the seeds of a woody vine
native to Brazil named for, the Guarani people,native to Brazil named for, the Guarani people,
who process the seeds for use in food, drink,who process the seeds for use in food, drink,
and medicine. Guarana containsand medicine. Guarana contains
concentrations of naturally occurring caffeineconcentrations of naturally occurring caffeine
higher than that found in coffee, tea, cacao,higher than that found in coffee, tea, cacao,
and kola. Guarana is sometimes marketed as aand kola. Guarana is sometimes marketed as a
natural alternative to caffeine, but it's caffeinenatural alternative to caffeine, but it's caffeine
all the same.all the same.
Caffeine !Caffeine !
Guarana contains a high amount of guaranine, a chemical substance with theGuarana contains a high amount of guaranine, a chemical substance with the
same characteristics as caffeine.same characteristics as caffeine.
This makes Guarana a stimulant similar to coffee:This makes Guarana a stimulant similar to coffee:
quickens perceptionsquickens perceptions
delays sleepdelays sleep
helps with endurance based activitieshelps with endurance based activities
can help to recover from a hangovercan help to recover from a hangover
impairs the appetiteimpairs the appetite

Caffeine god effectsCaffeine god effects
Caffeine
moderated
consumed
Improve
Social
interactions
Self-limiting
Drug
with
analgesic
action
Is
antidepressant
Provide
Alertness
Takes Adenosine’s
place
Performance
Enhancing
.

Any Question or
Comments?Comments?
National Soft Drink Association
How much caffeine is in your soda? : http://www.nsda.org/health/caffeinecontent.asp
ific.org/publications/brochures/upload/Caffeine-and-Women-s-Health.pdf
The International Food Information Council Foundation
assesses the effects of caffeine on pregnancy, fertility, cancer, osteoporosis, and heart disease.
PubMed from the National Library of Medicine
www.ncbi.nlm.nih.gov/entrez/query.fcgi
Search for current studies on caffeine and health. Often only abstracts are available, but they provide a
good overview of the results of the studies.
Mayo Clinic
http://www.mayoclinic.org/search/search-results?q=caffeine
Mayo Clinic staff answer food and nutrition questions, including queries about caffeine and kids, caffeine
content in beverages,etc.
How Caffeine Works
http://science.howstuffworks.com/caffeine.htm
Learn the origins of coffee drinking, how and where the beans are grown, and the science of caffeine.
Related links:Related links:

Bibliography:Bibliography:
 Fredholm, Bertil, and others. "Actions of Caffeine in the Brain With Special
Reference to Factors That Contribute to Its Widespread Use." Pharmacological
Reviews (March 1999), 83-133. Available online at
http://pharmrev.aspetjournals.org/content/51/1/83.full#SEC11_4.
 National Geographic http://ngm.nationalgeographic.com/ngm/0501/feature1/
* MacFarlane, Alan, and Iris MacFarlane. The Empire of Tea. Overlook Press,
2004.
* Maughan, R. J., and J. Griffin. "Caffeine Ingestion and Fluid Balance: A
Review." Journal of Human Nutrition and Dietetics (vol. 16, 2003), 411-20.
* Pendergrast, Mark. Uncommon Grounds: The History of Coffee and How It
Transformed Our World. Basic Books, 1999.
* Schivelbusch, Wolfgang. Tastes of Paradise: A Social History of Spices,
Stimulants, and Intoxicants. Pantheon Books, 1992.
* Weinberg, Bennett Alan, and Bonnie K. Bealer. The World of Caffeine: The