1. Eduardo E. Rivera Cintrón
UPR of Cayey Does the intake of coffee and tea really benefits our health?
Rise Program Abstract
Cancer is the most deadly disease known in all mankind. Every
year fatalities increase due to the complexity of this disease.
Coffee and tea are one of the most popular beverages in the
world. The average American drinks 3.2 cups of coffee equivalent
to 336 million cups of coffee a day. The intake of tea is also
considerably high in the United States and is increasing more
every time. Holick and collaborators (Brain Tumor), Islami and
collaborators (Tea and esophageal), and Villanueva and
collaborators stated that their study addresses the prevention of
brain tumors (coffee and tea), the risk bladder cancer (coffee) and
esophageal cancer (tea). All of the results depended on the
average intake of the beverage and how frequently the beverage
was consumed. Villanueva and collaborators conducted a study
where the result showed that drinking coffee four or more cups a
day showed an increase risk of bladder cancer. However, Holick
and collaborators concluded in their study that drinking five or
more cups of coffee and tea a day showed a reduction in the risk
of glioma tumors. In conclusion, the studies point to the
contradictory results in the intake of coffee and/or tea, confirming
that further studies are needed to discover whether the intake of
coffee and/or tea can cause cancer and if so, what ingredient(s)
may causes it.
Introduction cancer diseases. Cancer has been a topic
where every American is attentively
There may be no greater goal in the
listening to new discoveries and what they
American population, or even in the world’s
should know to be well prepared if in the
population, than to find the cure of various

2. Does the intake of coffee and tea really benefits our health?
near future they get the news that they or a Coffee is the major source of caffeine,
loved one has cancer. Cancer is becoming which has been reported to both stimulate
the greatest and most complex disease in the the central nervous system and suppress
history of mankind. Every day we identify brain tumors. There have been various
different risk factors that can cause cancer studies stating the inconsistency of a result
and the list of possible carcinogens is in coffee making it a potential carcinogenic.
greater. Every year we receive news on Studies have revealed that there is an
higher diagnostics of cancer deaths. Year- ingredient in coffee, not yet specified, that is
by-year the fear of this disease is greater labeled 2b carcinogens. Although the
because of the average mortality rate in the consumption of coffee has various health
world’s society. The main reason for such a benefits in our daily living, it also has
high mortality rate from cancer is due to the negative effects shown in recent studies.
highly invasive behavior of cancer cells,
Tea is known as the number one beverage
which usually results in cancer progression
worldwide and its consumption is increasing
and metastasis. Metastasis is the process
rapidly in the United States. Tea is generally
where neoplastic cells spread from a primary
consumed in the form of green (20%),
site, where the primary tumor originated, to
oolong (2%), or black (78%) tea, all of
distant organs and is responsible for the
which originate from the leaves of the plant
majority of deaths related to cancer.
Camellia sinensis (Naghma 2010). Tea and
(Naghma 2010)
its constituents have been shown to inhibit
Our main focus in this article is to inform tumor genesis in many animal models,
whether the consumption of coffee and/or including those for cancer of the skin, lung,
tea causes cancer or prevents it. In the oral cavity, esophagus, stomach, small
population of the United States 50% of intestine, colon, liver, pancreas, bladder,
Americans drink coffee averaging 3.1 cups breast and prostate (Kang et al. 2010).
of coffee a day. Coffee consumption has Recent studies reveal that tea contains an
been shown to be associated with cancer of ingredient called Tannin, a strong chemical,
various sites in epidemiological studies. which is linked to the risk of esophageal
However, there is not a comprehensive cancer. Although the consumption of tea is
overview of the substantial body of favorable for everyone because of its health
epidemiologic evidence. [Yu et al. 2011) benefits like antibiotic effects, increase of
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3. Does the intake of coffee and tea really benefits our health?
metabolic rate, anti-diabetes effect, boost to per day or more had an OR of 1.27 (95%CI
mental alertness, and others; tea may have a 0.88-1.81) (Villanueva et al. 2009). In
negative effect on the human being. addition, the consumption of coffee was
correlated with smoking habits. Among the
Risk of cancer in tea and coffee
group who didn’t smoke, the risk was found
Coffee and the risk of Bladder cancer only in the group who drank 4 or more cups
of coffee a day. These results supported their
Bladder cancer is one of the most commonly
hypothesis that coffee is a weak carcinogen.
diagnosed cancers in the U.S. Studies
suggest that coffee is possibly carcinogenic Tea and the risk of Esophageal Cancer
to urinary bladder, although evidence
Esophagus cancer kills nearly 500,000
remains controversial (Villanueva et al.
people a year. The areas in which the deaths
2009). A number of studies have reported a
are most often seen are in Asia, Africa, and
positive association that was not replicated
South America. The most common subtype
in other studies (Villanueva et al. 2009).
of esophagus cancer worldwide is
The study was conducted in Spain in 18
esophageal squamous cell carcinoma. The
hospitals located in five different areas.
main causes of this cancer are smoking and
Villanueva and collaborators identified
alcohol consumption. However, in the
1,457 cases and 1,465 eligible controls.
Eastern part of the world one of the causes is
They ask various questions to the
the consumption of hot tea, something that is
participants on how frequently they drank
commonly used in these countries. Studies
coffee, when did you first drink coffee, how
support the hypothesis that the consumptions
many times a week they drank coffee, and
of hot tea can cause esophageal cancer.
how many cups of coffee they drank per
Islami and collaborators concentrated their
day. Eighty seven percent of the study
study in the area of Golestan, Iran by
subjects consumed coffee (89% of cases,
conducting a case-control study and a cohort
85% of controls). By gender, 89% of men
study. In the cohort study participants,
vs. of 79% of women consumed coffee.
around 50,045 adults, had to answer various
Coffee consumer drank an average 2.4 cups
questions that were: do you drink tea, if so,
a day. Overall, the risk of bladder cancer
did they drink it warm, lukewarm, hot, or
among coffee drinkers was slightly
very hot. In the case-control study
increased. Drinkers of four cups of coffee
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4. Does the intake of coffee and tea really benefits our health?
participant’s nearly 300 cases and 571 beneficial compounds; however, such
controls answered the same questions as in activity has not been convincingly shown in
the cohort study. Researchers started at 75C human(Islami et al. 2007). The association
and drop 5C if the temperature wasn’t the between drinking hot beverages and the risk
one in which the participant drank the tea. of esophageal cancer suggests that thermal
Tea temperature was associated with the risk injury could be a cause of other cancers of
of esophageal squamous cell carcinoma. the upper aero digestive epithelia; however,
(Islami et al. 2007) Compared with drinking this hypothesis has been investigated in only
warm or lukewarm tea, drinking hot tea a few epidemiological studies. Even though
(odds ratio 2.07, 95% confidence interval the evidence shows that hot tea drinking
1.28 to 3.35) or very hot tea (8.16, 3.93 to causes esophageal cancer it’s too early to
16.91) was associated with an increased risk draw any conclusion. Further studies are
of esophageal cancer (P for trend <0.001). needed.
(Islami et al. 2007) What was also
Prevention of cancer
associated with the risk of esophageal cancer
was the interval between tea being poured Tea and Coffee associated with brain
and drunk. Compared with an interval of tumors
four or more minutes, intervals of 2-3
Coffee is of the most frequently consumed
minutes (odds ratio 2.49, 95% confidence
beverage in the world. Coffee is mainly
interval 1.62 to 3.83) and less than two
caffeine, which is known to be a stimulant of
minutes (5.41, 2.63 to 11.14) were
the central nervous system. There have been
associated with an increased risk of
only three epidemiologic studies that have
esophageal cancer (P for trend <0.001). In
examined the relationship between the
their study they concluded that the majority
intake of coffee and glioma risk. These
of the population drinks tea. They used more
studies showed a null result when examining
black tea, and it is the one they drink in large
them differently with other variables. When
amounts per day compared with green tea
researchers examined the tea alone, they did
that is rarely consumed in their population.
not find an association. On the other hand,
Both green and black tea has shown cancer
studying it combining coffee, tea and cola
prevention activity in animal models, which
drinks showed an inversed association. This
may be attributable to flavonoids and other
study is combining the data obtained by
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5. Does the intake of coffee and tea really benefits our health?
analyzing three large prospective studies on Discussion
men and women. Holick and collaborators
Previous research on coffee and/or tea states
conducted their study by asking the
the positive health benefits in the different
participants the sizes of their intakes of food.
types of cancer, in other diseases and
Individual intakes were calculated by
nutritional health. In spite of these results
multiplying the frequency of each food or
there have been contradictory effects related
beverage consumed by the nutrient content
to coffee and tea that show the contrary. At
of the specified portion size and then by
this point, we are aware of the various
summing the contribution from all foods and
benefits that coffee and tea provide. With
beverages. (Holick et al. 2010) In each
these results, people must take their cautions
questionnaire, participants were asked if
to moderate their intake of coffee and tea.
they had been diagnosed with any type of
Coffee and tea have been studied for years
cancer or medical disease during the past 2-
in various diseases. In the past decades,
years. Investigators evaluated every
researchers have revealed contradictory
questionnaire and the participants who
results. Cancer is a disease that is spreading
didn’t answer were called by phone and
fast in society. Due to the inconsistency of
interviewed. For (83%) of the men and 70%
the results further studies are required to
of the women in NHS I, glioblastoma was
reveal what ingredient is the possible
the most common histological type, while
carcinogen in coffee, and why the intake of
astrocytomas accounted for 14% of tumors
coffee and/or tea has contradictory effects
in men and 24% in women. (Holick et al.
on humans.
2010) However, there was a significantly
lower risk of glioma among men and women References
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