Table of Contents
Breast cancer
Prostate cancer
Liver cancer
Oral/pharyngeal cancer
Skin cancer
Endometrial cancer
Head
and neck cancers
Colorectal cancer
Breast cancer
A number of research studies have
shown that coffee helps to protect against breast cancer. A new study led by
Lund University, has confirmed that coffee inhibits the growth of tumours and
reduces the risk of recurrence in women who have been diagnosed with breast
cancer and treated with the drug tamoxifen.
The study, which is a follow-up of
the results the researchers obtained two years ago, was carried out at Lund
University and Skåne University Hospital, in collaboration with researchers in
the UK.
"Now, unlike in the previous
study, we have combined information about the patients' lifestyle and clinical
data from 1090 breast cancer patients with studies on breast cancer cells. The
study shows that among the over 500 women treated with tamoxifen, those who had
drunk at least two cups of coffee a day had only half the risk of recurrence of
those who drank less coffee or none at all", explain researchers Ann
Rosendahl and Helena Jernström, who obtained the results in collaboration with
Jeff Holly and his research team at University of Bristol.
"The study also shows that those
who drank at least two cups of coffee a day had smaller tumours and a lower
proportion of hormone-dependent tumours. We saw that this was already the case
at the time of diagnosis."
In the cell study, the researchers
looked more closely at two substances that usually occur in the coffee drunk in
Sweden - caffeine and caffeic acid.
"The breast cancer cells reacted
to these substances, especially caffeine, with reduced cell division and
increased cell death, especially in combination with tamoxifen. This shows that
these substances have an effect on the breast cancer cells and turn off
signalling pathways that the cancer cells require to grow."
The researchers have demonstrated
both in breast cancer patients and at cell level that coffee appears to
reinforce the effect of treatment with tamoxifen, but emphasise the importance
of taking prescribed medication.
"They are incredibly important, but if you like
coffee and are also taking tamoxifen, there is no reason to stop drinking it.
Just two cups a day is sufficient to make a difference."
Coffee may help prevent breast cancer returning
Drinking coffee
could decrease the risk of breast cancer recurring in patients taking the
widely used drug Tamoxifen, a study at Lund University in Sweden has found.
Patients who took the pill, along with two or more cups of coffee daily,
reported less than half the rate of cancer recurrence, compared with their
non-coffee drinking, Tamoxifen-taking counterparts.
The team
followed over 600 breast cancer patients from southern Sweden for an average of
five years. Approximately 300 took Tamoxifen. The drug, a common hormone therapy
after breast cancer surgery, reduces the risk of new tumours by blocking
oestrogen receptors. How coffee interacts with the treatment, however, isn't
immediately known.
"One theory
we are working with is that coffee 'activates' Tamoxifen and makes it more
efficient", says Maria Simonsson, doctoral student in Oncology at Lund
University.
The Lund
University researchers have previously linked coffee consumption to a decreased
risk of developing certain types of breast cancer. Caffeine has also been shown
to hamper the growth of cancer cells. The latest observational study involving
coffee's role in cancer prevention and treatment underlines the need for more
research, according to the team.
"We would
like to know more about how lifestyle can interact with breast cancer
treatment", says Helena Jernström, Associate Professor of Experimental
Oncology at Lund University.
Coffee Reduces Breast Cancer Risk
Recently
published research shows that coffee drinkers enjoy not only the taste of their
coffee but also a reduced risk of cancer with their cuppa. More detailed
research published May 10, 2011 in BioMed Central's open access journal Breast Cancer Research shows that
drinking coffee specifically reduces the risk of antiestrogen-resistant
estrogen-receptor (ER)-negative breast cancer.
Researchers from
Sweden compared lifestyle factors and coffee consumption between women with
breast cancer and age-matched women without. They found that coffee drinkers
had a lower incidence of breast cancer than women who rarely drank coffee.
However they also found that several lifestyle factors affected breast cancer
rates, such as age at menopause, exercise, weight, education, and a family
history of breast cancer. Once they had adjusted their data to account for
these other factors they found that the protective effect of coffee on breast
cancer was only measurable for ER-negative breast cancer.
The group from
Karolinska Institutet explained that, "There is often conflicting
information about the beneficial effects of coffee -- when we compared our
results to that of a German study we discovered that their data showed the same
trend, but the relationship was much weaker. We suggest that this may have
something to do with the way the coffee was prepared, or the type of bean
preferred. It is unlikely that the protective effect is due to phytoestrogens
present in coffee since there was no reduction in the incidence of ER-positive
cancer in this study."
So while it is
evident that coffee may have beneficial effects in protecting women from ER
negative breast cancer the exact mechanism and compounds involved are not yet
clear and not all types of coffee are the same.
Four
or more cups of coffee a day may keep prostate cancer recurrence and progression
away
Coffee
consumption is associated with a lower risk of prostate cancer recurrence and
progression, according to a new study by Fred Hutchinson Cancer Research Center
scientists in Cancer Causes &
Control.
Corresponding
author Janet L. Stanford, Ph.D., co-director of the Program in Prostate Cancer
Research in the Fred Hutch Public Health Sciences Division, conducted the study
to determine whether the bioactive compounds in coffee and tea may prevent
prostate cancer recurrence and delay progression of the disease.
Stanford and
colleagues found that men who drank four or more cups of coffee per day
experienced a 59 percent reduced risk of prostate cancer recurrence and/or
progression as compared to those who drank only one or fewer cups per week.
They did not,
however, find an association between coffee drinking and reduced mortality from
prostate cancer, although the study included too few men who died of prostate
cancer to address that issue separately.
First study to
assess the link between tea and prostate cancer outcomes
Regarding tea
consumption, the researchers did not find an associated reduction of prostate
cancer recurrence and/or progression. The study also did not draw any
conclusions regarding the impact of tea drinking on prostate-specific death.
“To our
knowledge, our study is the first to investigate the potential association
between tea consumption and prostate cancer outcomes,” the authors wrote. “It
is important to note, however, that few patients in our cohort were regular tea
drinkers and the highest category of tea consumption was one or more cups per
day. The association should be investigated in future studies that have access
to larger populations with higher levels of tea consumption.”
The
population-based study involved 1,001 prostate cancer survivors, aged 35-74
years old at the time of diagnosis between 2002-2005, who were residents of
King County, Wash. Participants answered questions regarding their diet and
beverage consumption two years prior to prostate cancer diagnosis using a
validated food frequency questionnaire, and were interviewed about demographic
and lifestyle information, family history of cancer, medication use and
prostate cancer screening history.
The researchers
followed up with patients more than five years after diagnosis to ascertain
whether the prostate cancer had recurred and/or progressed. Those who were
still living, willing to be contacted and had been diagnosed with
non-metastatic cancer were included in the follow-up effort.
Of the original
1,001 patients in the cohort, 630 answered questions regarding coffee intake,
fit the follow-up criteria and were included in the final analysis. Of those,
61 percent of the men consumed at least one cup of coffee per day and 12
percent consumed the highest amount: four or more cups per day.
The study also
evaluated daily coffee consumption in relation to prostate cancer-specific
death in 894 patients using data from the initial food frequency questionnaire.
After the median follow-up period of eight-and-a-half years, 125 of the men had
died, including 38 specifically from prostate cancer. Daily coffee consumption
was not associated with prostate cancer-specific mortality or other-cause
mortality, but with few deaths these analyses were limited.
“Our study differs
from previous ones because we used a composite definition of prostate cancer
recurrence/progression,” said first author Milan Geybels, a doctoral student at
Maastricht University in the Netherlands who was a graduate student in
Stanford’s Prostate Studies group at Fred Hutch when the study was conducted.
“We used detailed information on follow-up prostate-specific antigen levels,
use of secondary treatment for prostate cancer and data from scans and biopsies
to assess occurrence of metastases and cause-specific mortality during follow
up. Using these detailed data, we could determine whether a patient had
evidence of prostate cancer recurrence or progression.”
The results are
consistent with findings from Harvard’s Health Professionals Follow-up Study,
which found that men who drank six or more cups of coffee per day had a 60
percent decreased risk of metastatic/lethal prostate cancer as compared to
coffee abstainers.
Further research
is required to understand the mechanisms underlying the results of the study,
but biological activities associated with consumption of phytochemical
compounds found in coffee include anti-inflammatory and antioxidant effects and
modulation of glucose metabolism. These naturally occurring compounds include:
Caffeine, which
has properties that inhibit cell growth and encourage apoptosis, or programmed
cell death. Previous studies have found that caffeine consumption may reduce
the risk of several cancer types, including basal-cell carcinoma, glioma (a
cancer of the brain and central nervous system) and ovarian cancer.
Additional
studies needed to confirm whether coffee can prevent cancer recurrence
The researchers
emphasize that coffee or specific coffee components cannot be recommended for
secondary prevention of prostate cancer before the preventive effect has been
demonstrated in a randomized clinical trial. Further, there’s ongoing debate
about which components in coffee are anti-carcinogenic, and additional large,
prospective studies are needed to confirm whether coffee intake is beneficial
for secondary prevention.
Coffee drinking
may even be problematic for some men, Geybels said.
“Although coffee
is a commonly consumed beverage, we have to point out that increasing one’s
coffee intake may be harmful for some men. For instance, men with hypertension
may be vulnerable to the adverse effects of caffeine in coffee. Or, specific
components in coffee may raise serum cholesterol levels, posing a possible
threat to coronary health. Patients who have questions or concerns about their
coffee intake should discuss them with their general practitioner,” he said.
Coffee Consumption Associated with Reduced Risk of Advanced Prostate Cancer
While it is too
early for physicians to start advising their male patients to take up the habit
of regular coffee drinking, data presented at the American Association for
Cancer Research Frontiers in Cancer Prevention Research Conference revealed a
strong inverse association between coffee consumption and the risk of lethal
and advanced prostate cancers.
“Coffee has
effects on insulin and glucose metabolism as well as sex hormone levels, all of
which play a role in prostate cancer. It was plausible that there may be an
association between coffee and prostate cancer,” said Kathryn M. Wilson, Ph.D.,
a postdoctoral fellow at the Channing Laboratory, Harvard Medical School and
the Harvard School of Public Health.
In a prospective
investigation, Wilson and colleagues found that men who drank the most coffee
had a 60 percent lower risk of aggressive prostate cancer than men who did not
drink any coffee. This is the first study of its kind to look at both overall
risk of prostate cancer and risk of localized, advanced and lethal disease.
“Few studies
have looked prospectively at this association, and none have looked at coffee
and specific prostate cancer outcomes,” said Wilson. “We specifically looked at
different types of prostate cancer, such as advanced vs. localized cancers or
high-grade vs. low-grade cancers.”
Caffeine is
actually not the key factor in this association, according to Wilson. The
researchers are unsure which components of the beverage are most important, as
coffee contains many biologically active compounds like antioxidants and
minerals.
Using the Health
Professionals’ Follow-Up Study, the researchers documented the regular and
decaffeinated coffee intake of nearly 50,000 men every four years from 1986 to
2006; 4,975 of these men developed prostate cancer over that time. They also
examined the cross-sectional association between coffee consumption and levels
of circulating hormones in blood samples collected from a subset of men in the
cohort.
“Very few
lifestyle factors have been consistently associated with prostate cancer risk,
especially with risk of aggressive disease, so it would be very exciting if
this association is confirmed in other studies,” said Wilson. “Our results do
suggest there is no reason to stop drinking coffee out of any concern about
prostate cancer.”
This association
might also help understand the biology of prostate cancer and possible
chemoprevention measures.
Liver Cancer
Study Links Coffee to Lower Liver Cancer Risk
A new study
suggests that people who drink at least a cup a day have a lower risk of liver
cancer compared to those who only indulge occasionally.
The study was to
be presentedy at the 2014 meeting of the American Association of Cancer
Researchers in San Diego. Research presented at meetings should be viewed as
preliminary until published in a peer-reviewed medical journal.
When the study
started in the 1990s, researchers asked nearly 180,000 adults of different
racial and ethnic backgrounds about their coffee drinking and other lifestyle
habits.
Study
participants have now been tracked for as long as 18 years, and researchers
have kept tabs on how many have developed hepatocellular carcinoma, the most
common kind of liver cancer. So far, 498 study participants have been
diagnosed.
People who said
they drank one to three cups of coffee a day had a 29 percent reduced risk of
liver cancer compared to those who drank six cups or less each week. And more
was apparently better: People who regularly had more than four cups of coffee a
day had a 42 percent reduced risk, according to the study.
To put that in
perspective, one in 81 men and one in 196 women will get liver cancer over the
course of their lives, according to the American Cancer Society. A 29 percent
risk reduction lowers the odds of that diagnosis to one in 104 for men and one
in 253 for women.
What's more,
those reductions held even after researchers accounted for other things known
to increase a person's risk for liver cancer such as age, obesity, smoking,
drinking, sex and diabetes.
However, the
study was only designed to show association, not to prove a cause-and-effect
relationship. There may be something else common to coffee drinkers that also
reduces cancer risk.
Still, it's not
the first study to uncover such a link.
A review
published last year in the journal Clinical
Gastroenterology and Hepatology, which combined the results of 16 different
studies involving more than 3,200 patients, concluded that drinking more than
three cups of coffee a day might cut the risk of liver cancer by as much as 50
percent.
One expert
praised the most recent research.
"This is a
really well-done study," said Susan Gapstur, vice president of
epidemiology for the American Cancer Society. "It adds to the growing body
of evidence that coffee might be associated with a lower risk for a number of cancers."
Beyond liver
cancer, studies have suggested that coffee may be tied to reduced risk for head
and neck cancers, colorectal cancers, prostate cancer, and bladder,
endometrial, esophageal and pancreatic cancers.
What researchers
don't yet understand is how coffee may ward off cancer.
"That's
what everybody wants to know," said study author V. Wendy Setiawan, an
assistant professor in the department of preventive medicine at the USC Norris
Comprehensive Cancer Center in Los Angeles.
Setiawan says coffee
has close to 100 active compounds including antioxidants, polyphenols and
caffeine. It's also known to affect liver enzymes.
"At this
time, I don't think anybody has any idea what compound is protective," she
said.
Coffee consumption reduces risk of liver cancer
Coffee
consumption reduces risk of hepatocellular carcinoma (HCC), the most common
type of liver cancer, by about 40 percent, according to an up-to-date
meta-analysis published in Clinical
Gastroenterology and Hepatology, the official clinical practice journal of
the American Gastroenterological Association. Further, some data indicate that
three cups of coffee per day reduce liver cancer risk by more than 50 percent.
"Our
research confirms past claims that coffee is good for your health, and
particularly the liver," said Carlo La Vecchia, MD, study author from the
department of epidemiology, Istituto di Ricerche Farmacologiche "Mario
Negri," and department of clinical sciences and community health,
Università degli Studi di Milan, Italy. "The favorable effect of coffee on
liver cancer might be mediated by coffee's proven prevention of diabetes, a
known risk factor for the disease, or for its beneficial effects on cirrhosis
and liver enzymes."
Researchers
performed a meta-analysis of articles published from 1996 through September
2012, ultimately studying 16 high-quality studies and a total of 3,153 cases.
This research fills an important gap as the last meta-analysis was published in
2007, and since then there has been data published on more than 900 cases of
HCC.
Despite the
consistency of results across studies, time periods and populations, it is
difficult to establish whether the association between coffee drinking and HCC
is causal, or if this relationship may be partially attributable to the fact
that patients with liver and digestive diseases often voluntarily reduce their
coffee intake.
"It remains
unclear whether coffee drinking has an additional role in liver cancer
prevention," added Dr. La Vecchia. "But, in any case, such a role
would be limited as compared to what is achievable through the current
measures."
Primary liver
cancers are largely avoidable through hepatitis B virus vaccination, control of
hepatitis C virus transmission and reduction of alcohol drinking. These three measures
can, in principle, avoid more than 90 percent of primary liver cancer
worldwide.
Liver cancer is
the sixth most common cancer in the world, and the third most common cause of
cancer death. HCC is the main type of liver cancer, accounting for more than 90
percent of cases worldwide. Chronic infections with hepatitis B and C viruses
are the main causes of liver cancer; other relevant risk factors include
alcohol, tobacco, obesity and diabetes.
Higher
Coffee Consumption Associated with Lower Liver Cancer Risk
A large,
prospective population-based study confirms an inverse relationship between
coffee consumption and liver cancer risk. The study also found that higher
levels of gamma-glutamyltransferase (GGT) in the blood were associated with an
increased risk of developing the disease. These findings are published in Hepatology, a journal published by John
Wiley & Sons on behalf of the American Association for the Study of Liver
Diseases (AASLD).
Researchers
led by Gang Hu at the University of Helsinki set out to examine the
associations between coffee consumption and serum GGT with the risk of liver
cancer in a large prospective cohort. Residents of Finland drink more coffee
per capita than the Japanese, Americans, Italians, and other Europeans, so Hu
and colleagues studied 60,323 Finnish participants ages 25 to 74 who were
cancer-free at baseline. The Finns were included in seven independent cross-sectional
population surveys conducted between 1972 and 2002 and followed up through June
2006.
The participants
completed a mail-in questionnaire about their medical history, socioeconomic
factors and dietary and lifestyle habits. For a subset of participants,
clinical data was available, including serum levels of GGT. Data on subsequent
cancer diagnoses was collected from the country-wide Finnish Cancer Registry.
Based on their
answers to the question: “How many cups of coffee do you drink daily?” the participants
were divided into five categories: 0-1 cup, 2-3 cups, 4-5 cups, 6-7 cups, and 8
or more cups per day. After a median follow-up period of 19.3 years, 128
participants were diagnosed with liver cancer.
The researchers
noted a significant inverse association between coffee drinking and the risk of
primary liver cancer. They found that the multivariable hazards ratio of liver
cancer dropped for each group that drank more coffee. It fell from 1.00, to
.66, to .44, to .38 to .32 respectively. “The biological mechanisms behind the
association of coffee consumption with the risk of liver cancer are not known,”
the authors point out.
They also found
that high levels of serum GGT were associated with an increased risk of liver
cancer. The hazard ratio of liver cancer for the highest vs. lowest quartile of
serum GGT was 3.13. “Nevertheless,” they report, “the inverse association
between coffee consumption and the risk of liver cancer was consistent in the
subjects at any level of serum GGT.”
An accompanying
editorial by Carlo La Vecchia of Milan says that Hu’s study solidly confirms
the inverse relationship between coffee drinking and liver cancer risk, though
we still don’t know if it is causal. “Furthermore, the study by Hu et al.
provides original and important quantitative evidence that the levels of GGT
are related to subsequent incidence of liver cancer, with an overall relative
risk of 2.3,” he says.
La Vecchia
notes, however, that, “It remains difficult, however, to translate the inverse
relation between coffee drinking and liver cancer risk observed in
epidemiological studies into potential implications for prevention of liver
cancer by increasing coffee consumption.”
Oral/pharyngeal cancer
Caffeinated coffee may reduce the risk of oral cancers
A new (2012) American Cancer Society
study finds a strong inverse association between caffeinated coffee intake and
oral/pharyngeal cancer mortality. The authors say people who drank more than
four cups of caffeinated coffee per day were at about half the risk of death of
these often fatal cancers compared to those who only occasionally or who never
drank coffee. The study was published online in the American Journal of Epidemiology. The authors say more research is
needed to elucidate the biologic mechanisms that could be at work.
Previous epidemiologic studies have
suggested that coffee intake is associated with reduced risk of oral/pharyngeal
cancer. To explore the finding further, researchers examined associations of
caffeinated coffee, decaffeinated coffee, and tea intake with fatal
oral/pharyngeal cancer in the Cancer Prevention Study II, a prospective U.S.
cohort study begun in 1982 by the American Cancer Society.
Among 968,432 men and women who were
cancer-free at enrollment, 868 deaths due to oral/pharyngeal cancer occurred
during 26 years of follow-up. The researchers found consuming more than four
cups of caffeinated coffee per day was associated with a 49 percent lower risk
of oral/pharyngeal cancer death relative to no/occasional coffee intake (RR
0.51, 95% confidence interval [CI] 0.40-0.64). A dose-related decline in
relative risk was observed with each single cup per day consumed. The
association was independent of sex, smoking status, or alcohol use. There was a
suggestion of a similar link among those who drank more than two cups per day
of decaffeinated coffee, although that finding was only marginally significant.
No association was found for tea drinking.
The findings are novel in that they
are based specifically upon fatal cases of oral/pharyngeal cancer occurring
over a 26-year period in a population of prospectively-followed individuals who
were cancer-free at enrollment in Cancer Prevention Study II.
"Coffee is one of the most
widely consumed beverages in the world, and contains a variety of antioxidants,
polyphenols, and other biologically active compounds that may help to protect
against development or progression of cancers," said lead author Janet
Hildebrand, MPH. "Although it is less common in the United States,
oral/pharyngeal cancer is among the ten most common cancers in the world. Our
finding strengthens the evidence of a possible protective effect of caffeinated
coffee in the etiology and/or progression of cancers of the mouth and pharynx.
It may be of considerable interest to investigate whether coffee consumption
can lead to a better prognosis after oral/pharyngeal cancer diagnosis."
Skin cancer
Coffee consumption lowers risk of most common form of skin cancer
Increasing the
number of cups of caffeinated coffee you drink could lower your risk of
developing the most common form of skin cancer, basal cell carcinoma, according
to a study published in Cancer Research,
a journal of the American Association for Cancer Research.
"Our data
indicate that the more caffeinated coffee you consume, the lower your risk of
developing basal cell carcinoma," said Jiali Han, Ph.D., associate
professor at Brigham and Women's Hospital, Harvard Medical School in Boston and
Harvard School of Public Health.
"I would
not recommend increasing your coffee intake based on these data alone,"
said Han. "However, our results add basal cell carcinoma to a list of
conditions for which risk is decreased with increasing coffee consumption. This
list includes conditions with serious negative health consequences such as type
2 diabetes and Parkinson's disease."
Basal
cell carcinoma is the form of skin cancer most commonly diagnosed in the United
States. Even though it is slow-growing, it causes considerable morbidity and
places a burden on health care systems.
"Given the large
number of newly diagnosed cases, daily dietary changes having any protective
effect may have an impact on public health," said Han.
Han and his
colleagues generated their results by conducting a prospective analysis of data
from the Nurses' Health Study, a large and long-running study to aid in the
investigation of factors influencing women's health, and the Health
Professionals Follow-up Study, an analogous study for men.
Of the 112,897
participants included in the analyses, 22,786 developed basal cell carcinoma
during the more than 20 years of follow-up in the two studies. An inverse
association was observed between all coffee consumption and risk of basal cell
carcinoma. Similarly, an inverse association was seen between intake of
caffeine from all dietary sources (coffee, tea, cola and chocolate) and risk of
basal cell carcinoma. However, consumption of decaffeinated coffee was not
associated with a decreased risk of basal cell carcinoma.
Endometrial cancer
Coffee may protect against endometrial cancer
Long-term coffee
consumption may be associated with a reduced risk for endometrial cancer,
according to a recent study in Cancer
Epidemiology, Biomarkers & Prevention, a journal of the American
Association for Cancer Research.
Edward
Giovannucci, M.D., Sc.D., professor of nutrition and epidemiology at the
Harvard School of Public Health, said coffee is emerging as a protective agent
in cancers that are linked to obesity, estrogen and insulin.
"Coffee has
already been shown to be protective against diabetes due to its effect on
insulin," said Giovannucci, a senior researcher on the study. "So we
hypothesized that we'd see a reduction in some cancers as well."
Giovannucci,
along with Youjin Je, a doctoral candidate in his lab, and colleagues observed
cumulative coffee intake in relation to endometrial cancer in 67,470 women who
enrolled in the Nurses' Health Study.
During the
course of 26 years of follow-up, researchers documented 672 cases of
endometrial cancer.
Drinking more
than four cups of coffee per day was linked with a 25 percent reduced risk for
endometrial cancer. Drinking between two and three cups per day was linked with
a 7 percent reduced risk.
A similar link
was seen in decaffeinated coffee, where drinking more than two cups per day was
linked with a 22 percent reduced risk for endometrial cancer.
Giovannucci said
he hopes this study will lead to further inquiries about the effect of coffee
on cancer because in this and similar studies, coffee intake is self-selected
and not randomized.
"Coffee has
long been linked with smoking, and if you drink coffee and smoke, the positive
effects of coffee are going to be more than outweighed by the negative effects
of smoking," said Giovannucci. "However, laboratory testing has found
that coffee has much more antioxidants than most vegetables and fruits."
Coffee Reduces Breast Cancer Risk
Recently
published research shows that coffee drinkers enjoy not only the taste of their
coffee but also a reduced risk of cancer with their cuppa. More detailed
research published May 10, 2011 in BioMed Central's open access journal Breast Cancer Research shows that
drinking coffee specifically reduces the risk of antiestrogen-resistant
estrogen-receptor (ER)-negative breast cancer.
Researchers from
Sweden compared lifestyle factors and coffee consumption between women with
breast cancer and age-matched women without. They found that coffee drinkers
had a lower incidence of breast cancer than women who rarely drank coffee.
However they also found that several lifestyle factors affected breast cancer
rates, such as age at menopause, exercise, weight, education, and a family
history of breast cancer. Once they had adjusted their data to account for
these other factors they found that the protective effect of coffee on breast
cancer was only measurable for ER-negative breast cancer.
The group from
Karolinska Institutet explained that, "There is often conflicting
information about the beneficial effects of coffee -- when we compared our
results to that of a German study we discovered that their data showed the same
trend, but the relationship was much weaker. We suggest that this may have
something to do with the way the coffee was prepared, or the type of bean
preferred. It is unlikely that the protective effect is due to phytoestrogens
present in coffee since there was no reduction in the incidence of ER-positive
cancer in this study."
So while it is
evident that coffee may have beneficial effects in protecting women from ER
negative breast cancer the exact mechanism and compounds involved are not yet
clear and not all types of coffee are the same.
Coffee may protect against head and neck cancers
Data on the
effects of coffee on cancer risk have been mixed. However, results of a recent
study add to the brewing evidence that drinking coffee protects against cancer,
this time against head and neck cancer.
Full study
results were published in Cancer
Epidemiology, Biomarkers & Prevention, a journal of the American
Association for Cancer Research.
Using
information from a pooled-analysis of nine studies collected by the
International Head and Neck Cancer Epidemiology (INHANCE) consortium,
participants who were regular coffee drinkers, that is, those who drank an
estimated four or more cups a day, compared with those who were non-drinkers,
had a 39 percent decreased risk of oral cavity and pharynx cancers combined.
Data on
decaffeinated coffee was too sparse for detailed analysis, but indicated no
increased risk. Tea intake was not associated with head and neck cancer risk.
The association
is more reliable among those who are frequent, regular coffee drinkers,
consuming more than four cups of coffee a day.
"Since
coffee is so widely used and there is a relatively high incidence and low
survival rate of these forms of cancers, our results have important public
health implications that need to be further addressed," said lead
researcher Mia Hashibe, Ph.D., assistant professor in the department of family
and preventive medicine at the University of Utah, Salt Lake City, and a Huntsman
Cancer Institute investigator.
"What makes
our results so unique is that we had a very large sample size, and since we
combined data across many studies, we had more statistical power to detect
associations between cancer and coffee," she said.
At the AACR
Frontiers in Cancer Prevention Research Conference last December, researchers
from Harvard presented data that showed a strong inverse association between
coffee consumption and the risk of lethal and advanced prostate cancers — men
who drank the most coffee had a 60 percent lower risk of aggressive prostate
cancer than men who did not drink any coffee.
More recently,
results of another study published in Cancer
Epidemiology, Biomarkers & Prevention showed a decreased risk of
gliomas, or brain tumors, associated with coffee. This association was found
among those who drank five or more cups of coffee or tea a day, according the
researchers from the Imperial College, London.
Cancer
Epidemiology, Biomarkers & Prevention editorial board member Johanna W. Lampe,
Ph.D., R.D., believes this current analysis by Hashibe and colleagues provides
strong, additional evidence for an association between caffeinated coffee
drinking and cancer risk.
"The fact
that this was seen for oral and pharyngeal cancers, but not laryngeal cancers,
provides some evidence as to a possible specificity of effect," said
Lampe, who is a full member and associate division director in the division of
public health sciences at Fred Hutchinson Cancer Research Center, Seattle.,
Wash.
"These findings
provide further impetus to pursue research to understand the role of coffee in
head and neck cancer prevention," she added. Lampe is not associated with
this study.
Additional
research is warranted to characterize the importance of timing and duration of
exposure and possible mechanisms of action, according to Hashibe.
Coffee Consumption Associated with Reduced Risk of Advanced Prostate Cancer
While it is too
early for physicians to start advising their male patients to take up the habit
of regular coffee drinking, data presented at the American Association for
Cancer Research Frontiers in Cancer Prevention Research Conference revealed a
strong inverse association between coffee consumption and the risk of lethal
and advanced prostate cancers.
“Coffee has
effects on insulin and glucose metabolism as well as sex hormone levels, all of
which play a role in prostate cancer. It was plausible that there may be an
association between coffee and prostate cancer,” said Kathryn M. Wilson, Ph.D.,
a postdoctoral fellow at the Channing Laboratory, Harvard Medical School and
the Harvard School of Public Health.
In a prospective
investigation, Wilson and colleagues found that men who drank the most coffee
had a 60 percent lower risk of aggressive prostate cancer than men who did not
drink any coffee. This is the first study of its kind to look at both overall
risk of prostate cancer and risk of localized, advanced and lethal disease.
“Few studies
have looked prospectively at this association, and none have looked at coffee
and specific prostate cancer outcomes,” said Wilson. “We specifically looked at
different types of prostate cancer, such as advanced vs. localized cancers or
high-grade vs. low-grade cancers.”
Caffeine is
actually not the key factor in this association, according to Wilson. The
researchers are unsure which components of the beverage are most important, as
coffee contains many biologically active compounds like antioxidants and
minerals.
Using the Health
Professionals’ Follow-Up Study, the researchers documented the regular and
decaffeinated coffee intake of nearly 50,000 men every four years from 1986 to
2006; 4,975 of these men developed prostate cancer over that time. They also
examined the cross-sectional association between coffee consumption and levels
of circulating hormones in blood samples collected from a subset of men in the
cohort.
“Very few
lifestyle factors have been consistently associated with prostate cancer risk,
especially with risk of aggressive disease, so it would be very exciting if
this association is confirmed in other studies,” said Wilson. “Our results do
suggest there is no reason to stop drinking coffee out of any concern about
prostate cancer.”
This association
might also help understand the biology of prostate cancer and possible
chemoprevention measures.
Higher
Coffee Consumption Associated with Lower Liver Cancer Risk
A large,
prospective population-based study confirms an inverse relationship between
coffee consumption and liver cancer risk. The study also found that higher
levels of gamma-glutamyltransferase (GGT) in the blood were associated with an
increased risk of developing the disease. These findings are published in Hepatology, a journal published by John
Wiley & Sons on behalf of the American Association for the Study of Liver
Diseases (AASLD).
Researchers
led by Gang Hu at the University of Helsinki set out to examine the
associations between coffee consumption and serum GGT with the risk of liver
cancer in a large prospective cohort. Residents of Finland drink more coffee
per capita than the Japanese, Americans, Italians, and other Europeans, so Hu
and colleagues studied 60,323 Finnish participants ages 25 to 74 who were
cancer-free at baseline. The Finns were included in seven independent cross-sectional
population surveys conducted between 1972 and 2002 and followed up through June
2006.
The participants
completed a mail-in questionnaire about their medical history, socioeconomic
factors and dietary and lifestyle habits. For a subset of participants,
clinical data was available, including serum levels of GGT. Data on subsequent
cancer diagnoses was collected from the country-wide Finnish Cancer Registry.
Based on their
answers to the question: “How many cups of coffee do you drink daily?” the participants
were divided into five categories: 0-1 cup, 2-3 cups, 4-5 cups, 6-7 cups, and 8
or more cups per day. After a median follow-up period of 19.3 years, 128
participants were diagnosed with liver cancer.
The researchers
noted a significant inverse association between coffee drinking and the risk of
primary liver cancer. They found that the multivariable hazards ratio of liver
cancer dropped for each group that drank more coffee. It fell from 1.00, to
.66, to .44, to .38 to .32 respectively. “The biological mechanisms behind the
association of coffee consumption with the risk of liver cancer are not known,”
the authors point out.
They also found
that high levels of serum GGT were associated with an increased risk of liver
cancer. The hazard ratio of liver cancer for the highest vs. lowest quartile of
serum GGT was 3.13. “Nevertheless,” they report, “the inverse association
between coffee consumption and the risk of liver cancer was consistent in the
subjects at any level of serum GGT.”
An accompanying
editorial by Carlo La Vecchia of Milan says that Hu’s study solidly confirms
the inverse relationship between coffee drinking and liver cancer risk, though
we still don’t know if it is causal. “Furthermore, the study by Hu et al.
provides original and important quantitative evidence that the levels of GGT
are related to subsequent incidence of liver cancer, with an overall relative
risk of 2.3,” he says.
La Vecchia
notes, however, that, “It remains difficult, however, to translate the inverse
relation between coffee drinking and liver cancer risk observed in
epidemiological studies into potential implications for prevention of liver
cancer by increasing coffee consumption.”
Regular
consumption of caffeinated coffee may help prevent the return of colon cancer
after treatment and improve the chances of a cure, according to a new, large
study from Dana-Farber Cancer Institute that reported this striking association
for the first time.
The
patients, all of them treated with surgery and chemotherapy for stage III colon
cancer, had the greatest benefit from consuming four or more cups of coffee a
day (about 460 milligrams of caffeine), according to the study published in the
Journal of Clinical Oncology. These patients were 42 percent less likely
to have their cancer return than non-coffee drinkers, and were 33 percent less
likely to die from cancer or any other cause.
Two to
three cups of coffee daily had a more modest benefit, while little protection
was associated with one cup or less, reported the researchers, led by Charles
Fuchs, MD, MPH, director of the Gastrointestinal Cancer Center at Dana-Farber.
First author is Brendan J. Guercio, MD, also of Dana-Farber.
The
study included nearly 1,000 patients who filled out dietary pattern questionnaires
early in the study, during chemotherapy and again about a year later. This
"prospective" design eliminated patients' need to recall their
coffee-drinking habits years later -- a source of potential bias in many
observational studies.
"We
found that coffee drinkers had a lower risk of the cancer coming back and a
significantly greater survival and chance of a cure," Fuchs said. Most
recurrences happen within five years of treatment and are uncommon after that,
he noted. In patients with stage III disease, the cancer has been found in the
lymph nodes near the original tumor but there are no signs of further
metastasis. Fuchs said these patients have about a 35 percent chance of
recurrence.
As
encouraging as the results appear to be, Fuchs is hesitant to make
recommendations to patients until the results are confirmed in other studies.
"If you are a coffee drinker and are being treated for colon cancer, don't
stop," he said. "But if you're not a coffee drinker and wondering
whether to start, you should first discuss it with your physician."
Fuchs
said the study is the first to study an association between caffeinated coffee
and risk of colon cancer recurrence. It adds to a number of recent studies
suggesting that coffee may have protective effects against the development of
several kinds of cancer, including reduced risks of postmenopausal breast
cancer, melanoma, liver cancer, advanced prostate cancer.
Fuchs
said the research focused on coffee and other dietary factors because coffee
drinking -- in addition to possibly being protective against some cancers --
had been shown to reduce the risk of type 2 diabetes. Risk factors for diabetes
-- obesity, a sedentary life style, a Western diet high in calories and sugar,
and high levels of insulin -- are also implicated in colon cancer.
In
analyzing the results of the new study, Fuchs and his colleagues discovered
that the lowered risk of cancer recurrence and deaths was entirely due to
caffeine and not other components of coffee. He said it's not clear why
caffeine has this effect and the question needs further study. One hypothesis
is that caffeine consumption increases the body's sensitivity to insulin so
less of it is needed, which in turn may help reduce inflammation -- a risk
factor for diabetes and cancer, Fuchs said.
Other
than drinking coffee, Fuchs said, people can take other measures to reduce
cancer risks -- avoiding obesity, exercising regularly, adopting a healthier
diet, and eating nuts, which also reduce the risk of diabetes.
A number of research studies have
shown that coffee helps to protect against breast cancer. A new study led by
Lund University, has confirmed that coffee inhibits the growth of tumours and
reduces the risk of recurrence in women who have been diagnosed with breast
cancer and treated with the drug tamoxifen.
The study, which is a follow-up of
the results the researchers obtained two years ago, was carried out at Lund
University and Skåne University Hospital, in collaboration with researchers in
the UK.
"Now, unlike in the previous
study, we have combined information about the patients' lifestyle and clinical
data from 1090 breast cancer patients with studies on breast cancer cells. The
study shows that among the over 500 women treated with tamoxifen, those who had
drunk at least two cups of coffee a day had only half the risk of recurrence of
those who drank less coffee or none at all", explain researchers Ann
Rosendahl and Helena Jernström, who obtained the results in collaboration with
Jeff Holly and his research team at University of Bristol.
"The study also shows that those
who drank at least two cups of coffee a day had smaller tumours and a lower
proportion of hormone-dependent tumours. We saw that this was already the case
at the time of diagnosis."
In the cell study, the researchers
looked more closely at two substances that usually occur in the coffee drunk in
Sweden - caffeine and caffeic acid.
"The breast cancer cells reacted
to these substances, especially caffeine, with reduced cell division and
increased cell death, especially in combination with tamoxifen. This shows that
these substances have an effect on the breast cancer cells and turn off
signalling pathways that the cancer cells require to grow."
The researchers have demonstrated
both in breast cancer patients and at cell level that coffee appears to
reinforce the effect of treatment with tamoxifen, but emphasise the importance
of taking prescribed medication.
"They are incredibly important, but if you like
coffee and are also taking tamoxifen, there is no reason to stop drinking it.
Just two cups a day is sufficient to make a difference."
Coffee may help prevent breast cancer returning
Drinking coffee
could decrease the risk of breast cancer recurring in patients taking the
widely used drug Tamoxifen, a study at Lund University in Sweden has found.
Patients who took the pill, along with two or more cups of coffee daily,
reported less than half the rate of cancer recurrence, compared with their
non-coffee drinking, Tamoxifen-taking counterparts.
The team
followed over 600 breast cancer patients from southern Sweden for an average of
five years. Approximately 300 took Tamoxifen. The drug, a common hormone therapy
after breast cancer surgery, reduces the risk of new tumours by blocking
oestrogen receptors. How coffee interacts with the treatment, however, isn't
immediately known.
"One theory
we are working with is that coffee 'activates' Tamoxifen and makes it more
efficient", says Maria Simonsson, doctoral student in Oncology at Lund
University.
The Lund
University researchers have previously linked coffee consumption to a decreased
risk of developing certain types of breast cancer. Caffeine has also been shown
to hamper the growth of cancer cells. The latest observational study involving
coffee's role in cancer prevention and treatment underlines the need for more
research, according to the team.
"We would
like to know more about how lifestyle can interact with breast cancer
treatment", says Helena Jernström, Associate Professor of Experimental
Oncology at Lund University.
Four
or more cups of coffee a day may keep prostate cancer recurrence and progression
away
Coffee
consumption is associated with a lower risk of prostate cancer recurrence and
progression, according to a new study by Fred Hutchinson Cancer Research Center
scientists in Cancer Causes &
Control.
Corresponding
author Janet L. Stanford, Ph.D., co-director of the Program in Prostate Cancer
Research in the Fred Hutch Public Health Sciences Division, conducted the study
to determine whether the bioactive compounds in coffee and tea may prevent
prostate cancer recurrence and delay progression of the disease.
Stanford and
colleagues found that men who drank four or more cups of coffee per day
experienced a 59 percent reduced risk of prostate cancer recurrence and/or
progression as compared to those who drank only one or fewer cups per week.
They did not,
however, find an association between coffee drinking and reduced mortality from
prostate cancer, although the study included too few men who died of prostate
cancer to address that issue separately.
First study to
assess the link between tea and prostate cancer outcomes
Regarding tea
consumption, the researchers did not find an associated reduction of prostate
cancer recurrence and/or progression. The study also did not draw any
conclusions regarding the impact of tea drinking on prostate-specific death.
“To our
knowledge, our study is the first to investigate the potential association
between tea consumption and prostate cancer outcomes,” the authors wrote. “It
is important to note, however, that few patients in our cohort were regular tea
drinkers and the highest category of tea consumption was one or more cups per
day. The association should be investigated in future studies that have access
to larger populations with higher levels of tea consumption.”
The
population-based study involved 1,001 prostate cancer survivors, aged 35-74
years old at the time of diagnosis between 2002-2005, who were residents of
King County, Wash. Participants answered questions regarding their diet and
beverage consumption two years prior to prostate cancer diagnosis using a
validated food frequency questionnaire, and were interviewed about demographic
and lifestyle information, family history of cancer, medication use and
prostate cancer screening history.
The researchers
followed up with patients more than five years after diagnosis to ascertain
whether the prostate cancer had recurred and/or progressed. Those who were
still living, willing to be contacted and had been diagnosed with
non-metastatic cancer were included in the follow-up effort.
Of the original
1,001 patients in the cohort, 630 answered questions regarding coffee intake,
fit the follow-up criteria and were included in the final analysis. Of those,
61 percent of the men consumed at least one cup of coffee per day and 12
percent consumed the highest amount: four or more cups per day.
The study also
evaluated daily coffee consumption in relation to prostate cancer-specific
death in 894 patients using data from the initial food frequency questionnaire.
After the median follow-up period of eight-and-a-half years, 125 of the men had
died, including 38 specifically from prostate cancer. Daily coffee consumption
was not associated with prostate cancer-specific mortality or other-cause
mortality, but with few deaths these analyses were limited.
“Our study differs
from previous ones because we used a composite definition of prostate cancer
recurrence/progression,” said first author Milan Geybels, a doctoral student at
Maastricht University in the Netherlands who was a graduate student in
Stanford’s Prostate Studies group at Fred Hutch when the study was conducted.
“We used detailed information on follow-up prostate-specific antigen levels,
use of secondary treatment for prostate cancer and data from scans and biopsies
to assess occurrence of metastases and cause-specific mortality during follow
up. Using these detailed data, we could determine whether a patient had
evidence of prostate cancer recurrence or progression.”
The results are
consistent with findings from Harvard’s Health Professionals Follow-up Study,
which found that men who drank six or more cups of coffee per day had a 60
percent decreased risk of metastatic/lethal prostate cancer as compared to
coffee abstainers.
Further research
is required to understand the mechanisms underlying the results of the study,
but biological activities associated with consumption of phytochemical
compounds found in coffee include anti-inflammatory and antioxidant effects and
modulation of glucose metabolism. These naturally occurring compounds include:
Caffeine, which
has properties that inhibit cell growth and encourage apoptosis, or programmed
cell death. Previous studies have found that caffeine consumption may reduce
the risk of several cancer types, including basal-cell carcinoma, glioma (a
cancer of the brain and central nervous system) and ovarian cancer.
Additional
studies needed to confirm whether coffee can prevent cancer recurrence
The researchers
emphasize that coffee or specific coffee components cannot be recommended for
secondary prevention of prostate cancer before the preventive effect has been
demonstrated in a randomized clinical trial. Further, there’s ongoing debate
about which components in coffee are anti-carcinogenic, and additional large,
prospective studies are needed to confirm whether coffee intake is beneficial
for secondary prevention.
Coffee drinking
may even be problematic for some men, Geybels said.
“Although coffee
is a commonly consumed beverage, we have to point out that increasing one’s
coffee intake may be harmful for some men. For instance, men with hypertension
may be vulnerable to the adverse effects of caffeine in coffee. Or, specific
components in coffee may raise serum cholesterol levels, posing a possible
threat to coronary health. Patients who have questions or concerns about their
coffee intake should discuss them with their general practitioner,” he said.
Study Links Coffee to Lower Liver Cancer Risk
A new study
suggests that people who drink at least a cup a day have a lower risk of liver
cancer compared to those who only indulge occasionally.
The study was to
be presentedy at the 2014 meeting of the American Association of Cancer
Researchers in San Diego. Research presented at meetings should be viewed as
preliminary until published in a peer-reviewed medical journal.
When the study
started in the 1990s, researchers asked nearly 180,000 adults of different
racial and ethnic backgrounds about their coffee drinking and other lifestyle
habits.
Study
participants have now been tracked for as long as 18 years, and researchers
have kept tabs on how many have developed hepatocellular carcinoma, the most
common kind of liver cancer. So far, 498 study participants have been
diagnosed.
People who said
they drank one to three cups of coffee a day had a 29 percent reduced risk of
liver cancer compared to those who drank six cups or less each week. And more
was apparently better: People who regularly had more than four cups of coffee a
day had a 42 percent reduced risk, according to the study.
To put that in
perspective, one in 81 men and one in 196 women will get liver cancer over the
course of their lives, according to the American Cancer Society. A 29 percent
risk reduction lowers the odds of that diagnosis to one in 104 for men and one
in 253 for women.
What's more,
those reductions held even after researchers accounted for other things known
to increase a person's risk for liver cancer such as age, obesity, smoking,
drinking, sex and diabetes.
However, the
study was only designed to show association, not to prove a cause-and-effect
relationship. There may be something else common to coffee drinkers that also
reduces cancer risk.
Still, it's not
the first study to uncover such a link.
A review
published last year in the journal Clinical
Gastroenterology and Hepatology, which combined the results of 16 different
studies involving more than 3,200 patients, concluded that drinking more than
three cups of coffee a day might cut the risk of liver cancer by as much as 50
percent.
One expert
praised the most recent research.
"This is a
really well-done study," said Susan Gapstur, vice president of
epidemiology for the American Cancer Society. "It adds to the growing body
of evidence that coffee might be associated with a lower risk for a number of cancers."
Beyond liver
cancer, studies have suggested that coffee may be tied to reduced risk for head
and neck cancers, colorectal cancers, prostate cancer, and bladder,
endometrial, esophageal and pancreatic cancers.
What researchers
don't yet understand is how coffee may ward off cancer.
"That's
what everybody wants to know," said study author V. Wendy Setiawan, an
assistant professor in the department of preventive medicine at the USC Norris
Comprehensive Cancer Center in Los Angeles.
Setiawan says coffee
has close to 100 active compounds including antioxidants, polyphenols and
caffeine. It's also known to affect liver enzymes.
"At this
time, I don't think anybody has any idea what compound is protective," she
said.
Coffee consumption reduces risk of liver cancer
Coffee
consumption reduces risk of hepatocellular carcinoma (HCC), the most common
type of liver cancer, by about 40 percent, according to an up-to-date
meta-analysis published in Clinical
Gastroenterology and Hepatology, the official clinical practice journal of
the American Gastroenterological Association. Further, some data indicate that
three cups of coffee per day reduce liver cancer risk by more than 50 percent.
"Our
research confirms past claims that coffee is good for your health, and
particularly the liver," said Carlo La Vecchia, MD, study author from the
department of epidemiology, Istituto di Ricerche Farmacologiche "Mario
Negri," and department of clinical sciences and community health,
Università degli Studi di Milan, Italy. "The favorable effect of coffee on
liver cancer might be mediated by coffee's proven prevention of diabetes, a
known risk factor for the disease, or for its beneficial effects on cirrhosis
and liver enzymes."
Researchers
performed a meta-analysis of articles published from 1996 through September
2012, ultimately studying 16 high-quality studies and a total of 3,153 cases.
This research fills an important gap as the last meta-analysis was published in
2007, and since then there has been data published on more than 900 cases of
HCC.
Despite the
consistency of results across studies, time periods and populations, it is
difficult to establish whether the association between coffee drinking and HCC
is causal, or if this relationship may be partially attributable to the fact
that patients with liver and digestive diseases often voluntarily reduce their
coffee intake.
"It remains
unclear whether coffee drinking has an additional role in liver cancer
prevention," added Dr. La Vecchia. "But, in any case, such a role
would be limited as compared to what is achievable through the current
measures."
Primary liver
cancers are largely avoidable through hepatitis B virus vaccination, control of
hepatitis C virus transmission and reduction of alcohol drinking. These three measures
can, in principle, avoid more than 90 percent of primary liver cancer
worldwide.
Liver cancer is
the sixth most common cancer in the world, and the third most common cause of
cancer death. HCC is the main type of liver cancer, accounting for more than 90
percent of cases worldwide. Chronic infections with hepatitis B and C viruses
are the main causes of liver cancer; other relevant risk factors include
alcohol, tobacco, obesity and diabetes.
Caffeinated coffee may reduce the risk of oral cancers
A new (2012) American Cancer Society
study finds a strong inverse association between caffeinated coffee intake and
oral/pharyngeal cancer mortality. The authors say people who drank more than
four cups of caffeinated coffee per day were at about half the risk of death of
these often fatal cancers compared to those who only occasionally or who never
drank coffee. The study was published online in the American Journal of Epidemiology. The authors say more research is
needed to elucidate the biologic mechanisms that could be at work.
Previous epidemiologic studies have
suggested that coffee intake is associated with reduced risk of oral/pharyngeal
cancer. To explore the finding further, researchers examined associations of
caffeinated coffee, decaffeinated coffee, and tea intake with fatal
oral/pharyngeal cancer in the Cancer Prevention Study II, a prospective U.S.
cohort study begun in 1982 by the American Cancer Society.
Among 968,432 men and women who were
cancer-free at enrollment, 868 deaths due to oral/pharyngeal cancer occurred
during 26 years of follow-up. The researchers found consuming more than four
cups of caffeinated coffee per day was associated with a 49 percent lower risk
of oral/pharyngeal cancer death relative to no/occasional coffee intake (RR
0.51, 95% confidence interval [CI] 0.40-0.64). A dose-related decline in
relative risk was observed with each single cup per day consumed. The
association was independent of sex, smoking status, or alcohol use. There was a
suggestion of a similar link among those who drank more than two cups per day
of decaffeinated coffee, although that finding was only marginally significant.
No association was found for tea drinking.
The findings are novel in that they
are based specifically upon fatal cases of oral/pharyngeal cancer occurring
over a 26-year period in a population of prospectively-followed individuals who
were cancer-free at enrollment in Cancer Prevention Study II.
"Coffee is one of the most
widely consumed beverages in the world, and contains a variety of antioxidants,
polyphenols, and other biologically active compounds that may help to protect
against development or progression of cancers," said lead author Janet
Hildebrand, MPH. "Although it is less common in the United States,
oral/pharyngeal cancer is among the ten most common cancers in the world. Our
finding strengthens the evidence of a possible protective effect of caffeinated
coffee in the etiology and/or progression of cancers of the mouth and pharynx.
It may be of considerable interest to investigate whether coffee consumption
can lead to a better prognosis after oral/pharyngeal cancer diagnosis."
Coffee consumption lowers risk of most common form of skin cancer
Increasing the
number of cups of caffeinated coffee you drink could lower your risk of
developing the most common form of skin cancer, basal cell carcinoma, according
to a study published in Cancer Research,
a journal of the American Association for Cancer Research.
"Our data
indicate that the more caffeinated coffee you consume, the lower your risk of
developing basal cell carcinoma," said Jiali Han, Ph.D., associate
professor at Brigham and Women's Hospital, Harvard Medical School in Boston and
Harvard School of Public Health.
"I would
not recommend increasing your coffee intake based on these data alone,"
said Han. "However, our results add basal cell carcinoma to a list of
conditions for which risk is decreased with increasing coffee consumption. This
list includes conditions with serious negative health consequences such as type
2 diabetes and Parkinson's disease."
Basal
cell carcinoma is the form of skin cancer most commonly diagnosed in the United
States. Even though it is slow-growing, it causes considerable morbidity and
places a burden on health care systems.
"Given the large
number of newly diagnosed cases, daily dietary changes having any protective
effect may have an impact on public health," said Han.
Han and his
colleagues generated their results by conducting a prospective analysis of data
from the Nurses' Health Study, a large and long-running study to aid in the
investigation of factors influencing women's health, and the Health
Professionals Follow-up Study, an analogous study for men.
Of the 112,897
participants included in the analyses, 22,786 developed basal cell carcinoma
during the more than 20 years of follow-up in the two studies. An inverse
association was observed between all coffee consumption and risk of basal cell
carcinoma. Similarly, an inverse association was seen between intake of
caffeine from all dietary sources (coffee, tea, cola and chocolate) and risk of
basal cell carcinoma. However, consumption of decaffeinated coffee was not
associated with a decreased risk of basal cell carcinoma.
Coffee may protect against endometrial cancer
Long-term coffee
consumption may be associated with a reduced risk for endometrial cancer,
according to a recent study in Cancer
Epidemiology, Biomarkers & Prevention, a journal of the American
Association for Cancer Research.
Edward
Giovannucci, M.D., Sc.D., professor of nutrition and epidemiology at the
Harvard School of Public Health, said coffee is emerging as a protective agent
in cancers that are linked to obesity, estrogen and insulin.
"Coffee has
already been shown to be protective against diabetes due to its effect on
insulin," said Giovannucci, a senior researcher on the study. "So we
hypothesized that we'd see a reduction in some cancers as well."
Giovannucci,
along with Youjin Je, a doctoral candidate in his lab, and colleagues observed
cumulative coffee intake in relation to endometrial cancer in 67,470 women who
enrolled in the Nurses' Health Study.
During the
course of 26 years of follow-up, researchers documented 672 cases of
endometrial cancer.
Drinking more
than four cups of coffee per day was linked with a 25 percent reduced risk for
endometrial cancer. Drinking between two and three cups per day was linked with
a 7 percent reduced risk.
A similar link
was seen in decaffeinated coffee, where drinking more than two cups per day was
linked with a 22 percent reduced risk for endometrial cancer.
Giovannucci said
he hopes this study will lead to further inquiries about the effect of coffee
on cancer because in this and similar studies, coffee intake is self-selected
and not randomized.
"Coffee has
long been linked with smoking, and if you drink coffee and smoke, the positive
effects of coffee are going to be more than outweighed by the negative effects
of smoking," said Giovannucci. "However, laboratory testing has found
that coffee has much more antioxidants than most vegetables and fruits."
Head and neck cancers
Coffee may protect against head and neck cancers
Data on the
effects of coffee on cancer risk have been mixed. However, results of a recent
study add to the brewing evidence that drinking coffee protects against cancer,
this time against head and neck cancer.
Full study
results were published in Cancer
Epidemiology, Biomarkers & Prevention, a journal of the American
Association for Cancer Research.
Using
information from a pooled-analysis of nine studies collected by the
International Head and Neck Cancer Epidemiology (INHANCE) consortium,
participants who were regular coffee drinkers, that is, those who drank an
estimated four or more cups a day, compared with those who were non-drinkers,
had a 39 percent decreased risk of oral cavity and pharynx cancers combined.
Data on
decaffeinated coffee was too sparse for detailed analysis, but indicated no
increased risk. Tea intake was not associated with head and neck cancer risk.
The association
is more reliable among those who are frequent, regular coffee drinkers,
consuming more than four cups of coffee a day.
"Since
coffee is so widely used and there is a relatively high incidence and low
survival rate of these forms of cancers, our results have important public
health implications that need to be further addressed," said lead
researcher Mia Hashibe, Ph.D., assistant professor in the department of family
and preventive medicine at the University of Utah, Salt Lake City, and a Huntsman
Cancer Institute investigator.
"What makes
our results so unique is that we had a very large sample size, and since we
combined data across many studies, we had more statistical power to detect
associations between cancer and coffee," she said.
At the AACR
Frontiers in Cancer Prevention Research Conference last December, researchers
from Harvard presented data that showed a strong inverse association between
coffee consumption and the risk of lethal and advanced prostate cancers — men
who drank the most coffee had a 60 percent lower risk of aggressive prostate
cancer than men who did not drink any coffee.
More recently,
results of another study published in Cancer
Epidemiology, Biomarkers & Prevention showed a decreased risk of
gliomas, or brain tumors, associated with coffee. This association was found
among those who drank five or more cups of coffee or tea a day, according the
researchers from the Imperial College, London.
Cancer
Epidemiology, Biomarkers & Prevention editorial board member Johanna W. Lampe,
Ph.D., R.D., believes this current analysis by Hashibe and colleagues provides
strong, additional evidence for an association between caffeinated coffee
drinking and cancer risk.
"The fact
that this was seen for oral and pharyngeal cancers, but not laryngeal cancers,
provides some evidence as to a possible specificity of effect," said
Lampe, who is a full member and associate division director in the division of
public health sciences at Fred Hutchinson Cancer Research Center, Seattle.,
Wash.
"These findings
provide further impetus to pursue research to understand the role of coffee in
head and neck cancer prevention," she added. Lampe is not associated with
this study.
Additional
research is warranted to characterize the importance of timing and duration of
exposure and possible mechanisms of action, according to Hashibe.
Colorectal cancer
New study links coffee consumption to decreased risk of colorectal cancer
The study examined over 5,100 men and women who had been diagnosed with colorectal cancer within the past six months, along with an additional 4,000 men and women with no history of colorectal cancer to serve as a control group. Participants reported their daily consumption of boiled (espresso), instant, decaffeinated and filtered coffee, as well as their total consumption of other liquids. A questionnaire also gathered information about many other factors that influence the risk of colorectal cancer, including family history of cancer, diet, physical activity and smoking.
"We found that drinking coffee is associated with lower risk of colorectal cancer, and the more coffee consumed, the lower the risk," said Stephen Gruber, MD, PhD, MPH, director of the USC Norris Comprehensive Cancer Center and senior author of the study.
The data showed that even moderate coffee consumption, between one to two servings a day, was associated with a 26 percent reduction in the odds of developing colorectal cancer after adjusting for known risk factors. Moreover, the risk of developing colorectal cancer continued to decrease to up to 50 percent when participants drank more than 2.5 servings of coffee each day. The indication of decreased risk was seen across all types of coffee, both caffeinated and decaffeinated.
"We were somewhat surprised to see that caffeine did not seem to matter," Gruber said. "This indicates that caffeine alone is not responsible for coffee's protective properties."
Coffee contains many elements that contribute to overall colorectal health and may explain the preventive properties. Caffeine and polyphenol can act as antioxidants, limiting the growth of potential colon cancer cells. Melanoidins generated during the roasting process have been hypothesized to encourage colon mobility. Diterpenes may prevent cancer by enhancing the body's defense against oxidative damage.
"The levels of beneficial compounds per serving of coffee vary depending on the bean, roast and brewing method," said first author Stephanie Schmit, PhD, MPH. "The good news is that our data presents a decreased risk of colorectal cancer regardless of what flavor or form of coffee you prefer."
This extensive study was conducted by a research team led by Gad Rennert, MD, PhD, director of the Clalit National Israeli Cancer Control Center in Haifa, Israel, together with investigators at USC Norris. One advantage of this large, population-based study is that the results are representative of many coffee-drinking populations.
"Although coffee consumption in Israel is less common and with more type-variability than in the United States, our results indicate similarities in risk reduction with use consumption of various types of coffee," Rennert said.
The study is available in the April 1, 2016 issue of Cancer Epidemiology, Biomarkers & Prevention, which is published by the American Association of Cancer Research.
"While the evidence certainly suggests this to be the case, we need additional research before advocating for coffee consumption as a preventive measure," Gruber added. That being said, there are few health risks to coffee consumption, I would encourage coffee lovers to revel in the strong possibility that their daily mug may lower their risk of colorectal cancer."
Colorectal cancer is the third most common cancer that is diagnosed in both men and women in the United States, with nearly five percent of men and just over four percent of women developing the disease over their lifetime. The American Cancer Society (ACS) estimates that in the United States, over 95,000 new cases of colon cancer and 39,000 new cases of rectal cancer will be diagnosed in this year alone.
Regular
consumption of caffeinated coffee may help prevent the return of colon cancer
after treatment and improve the chances of a cure, according to a new, large
study from Dana-Farber Cancer Institute that reported this striking association
for the first time.
The
patients, all of them treated with surgery and chemotherapy for stage III colon
cancer, had the greatest benefit from consuming four or more cups of coffee a
day (about 460 milligrams of caffeine), according to the study published in the
Journal of Clinical Oncology. These patients were 42 percent less likely
to have their cancer return than non-coffee drinkers, and were 33 percent less
likely to die from cancer or any other cause.
Two to
three cups of coffee daily had a more modest benefit, while little protection
was associated with one cup or less, reported the researchers, led by Charles
Fuchs, MD, MPH, director of the Gastrointestinal Cancer Center at Dana-Farber.
First author is Brendan J. Guercio, MD, also of Dana-Farber.
The
study included nearly 1,000 patients who filled out dietary pattern questionnaires
early in the study, during chemotherapy and again about a year later. This
"prospective" design eliminated patients' need to recall their
coffee-drinking habits years later -- a source of potential bias in many
observational studies.
"We
found that coffee drinkers had a lower risk of the cancer coming back and a
significantly greater survival and chance of a cure," Fuchs said. Most
recurrences happen within five years of treatment and are uncommon after that,
he noted. In patients with stage III disease, the cancer has been found in the
lymph nodes near the original tumor but there are no signs of further
metastasis. Fuchs said these patients have about a 35 percent chance of
recurrence.
As
encouraging as the results appear to be, Fuchs is hesitant to make
recommendations to patients until the results are confirmed in other studies.
"If you are a coffee drinker and are being treated for colon cancer, don't
stop," he said. "But if you're not a coffee drinker and wondering
whether to start, you should first discuss it with your physician."
Fuchs
said the study is the first to study an association between caffeinated coffee
and risk of colon cancer recurrence. It adds to a number of recent studies
suggesting that coffee may have protective effects against the development of
several kinds of cancer, including reduced risks of postmenopausal breast
cancer, melanoma, liver cancer, advanced prostate cancer.
Fuchs
said the research focused on coffee and other dietary factors because coffee
drinking -- in addition to possibly being protective against some cancers --
had been shown to reduce the risk of type 2 diabetes. Risk factors for diabetes
-- obesity, a sedentary life style, a Western diet high in calories and sugar,
and high levels of insulin -- are also implicated in colon cancer.
In
analyzing the results of the new study, Fuchs and his colleagues discovered
that the lowered risk of cancer recurrence and deaths was entirely due to
caffeine and not other components of coffee. He said it's not clear why
caffeine has this effect and the question needs further study. One hypothesis
is that caffeine consumption increases the body's sensitivity to insulin so
less of it is needed, which in turn may help reduce inflammation -- a risk
factor for diabetes and cancer, Fuchs said.
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