Obesity and Cancer Risk: A Global Perspective (HSCI101, Semester 1)

Desklib provides past papers and solved assignments for students. This essay explores the link between obesity and cancer.

AYOADE: EVIDENCE BASED
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Table of Contents
Introduction......................................................................................................................................2
Methods of evidence search.............................................................................................................2
Analysis and Discussion..................................................................................................................3
Researches which supports the fact.............................................................................................4
Researches which doesn't support the fact...................................................................................7
Type of Evidence being shown....................................................................................................8
Research Process..........................................................................................................................8
Problems during research.............................................................................................................9
Conclusion.....................................................................................................................................10
Reference List................................................................................................................................11
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Introduction
The research paper based on the topic "Global patterns in Excess Body Weight and the
Associated Cancer Burden" by Sung et al. (2018) has focused on the association between obesity
and cancer by providing global evidence. The case scenario has provided a clear concept of
excessive body weight and how it relates to cancer. It is noticed from the research that there is an
increased rate of cancer because of excess body weight. The key drivers of the global increase in
obesity are identified in the case scenario. Variation of body weight in different regions
internationally is highlighted to indicate the global patterns. The study provides evidence of
different types of cancer caused by obesity including colon cancer, breast cancer, liver cancers,
thyroid, and kidney cancer and so on. Moreover, the variation of this deadly disease between
men and women are identified. Therefore, the research paper has provided a comprehensive
discussion on the global patterns of obesity and its impact on cancer risk.
Over the years, the obesity rate has increased globally due to various factors such as a change in
lifestyle, national wealth, and environment and so on. It has significantly increased concern for
cancer risk. It is necessary to understand the influential factors of excessive body weight in
different countries. Epidemiological concept related to the link between obesity and cancer is
also necessary to understand. These are the main reason behind conducting the chosen research.
The research paper has indicated obesity as a global issue which should be considered by every
citizen to avoid cancer risks.
The case scenario proposes that the people from every region globally should be aware of the
fact excessive obesity can be a major reason behind cancer. It also provides some policies and
actions to deal with excessive body weights. Some evidences are also provided where people
have survived cancer despite having excessive body weights. In relation to this, the current paper
provides an evidence-based essay by analyzing the key findings of the chosen case scenario.
Various related findings from other researchers which support and don't support the link between
obesity and cancer are also analyzed in this paper.
Methods of evidence search
Search process
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A number of journals, articles and websites are searched for investigating on the chosen topic
that is obesity and cancer risk. That means the literature of this essay is mainly based on the
secondary resources produced by previous researchers. It is ensured that each of these resources
is easily available and provides true and honest information related to the topic.
Databases
Considering the databases, the resources are collected from online databases that are searching
on the Internet. The google scholar is one of the best search engines to collect quality articles
conducted by different researchers. Therefore, the main sources of this paper are collected from
the research papers uploaded online.
Search Terms
It is important to use the correct search terms while collecting information from the Internet. The
key terms that have been used during the online research include "obesity and cancer risks", "link
between obesity and cancer", "how obesity cause cancer", Impact of excessive of body weight on
cancer". As the topic is a common area of research, finding the most relevant content was not
difficult.
Date Range
The researcher mainly focused on the current information related to this topic. The date range
that has been used for the research is 2014-2019. The essay analyzes the findings of the previous
six years to support the chosen article.
Number of journals
A range of journal articles and websites are taken into account to provide comprehensive
analysis related to the chosen subject area. A total number of 12 resources are used in this paper
including the selected article. 9 journal articles and 3 relevant websites are accessed to collect the
required information. It is ensured that the sources are quality resources and being used for
academic work rather than commercial purposes.
Analysis and Discussion
The main body of this essay provides a summary of the findings of this chosen article. In
addition, various other journal articles which for and against the claim that is obesity can cause
cancer are discussed.
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Researches which supports the fact
The case scenario has mainly emphasized on the global patterns of excessive body weights and
its impact on the increasing rate of cancer globally. According to Sung et al. (2018), BMI or
Body Mass Index is the most frequently used measure of body wights to classify the level of
obesity. It has been noticed that the average BMI among the adults of 20 years has increased
from 21.7 kg/m2 to 24.5 kg/m2 during the period of 1976-2016. During this era, the largest
increase (from 9% to 30%) is noticed among the men in wealthy western countries as well as
among the women in North Africa, Middles East and Central Asia (from 12% to 30%).
Therefore, considering the demographics of people, growing rate of excessive weights has
become a global concern.
The case scenario also identifies some key drivers to this increased rate. It includes economic
systems that promote high growth of the food industry and consumption, increased food supply
which promotes the intake of energy-dense food, national wealth, cultural body size preferences,
and leisure activities and so on. Genetic susceptibility can also be influential factors of obesity.
Reports from IARC (International Agency for Research on Cancer) have provided a number of
cancer evidence caused by obesity. It is found from the case study that, a total number of
368,500 crores (men) and 175,800 crores (women) cases are reported globally in the last decade.
Breast cancer is the most common type of cancer (31% among all types) followed by
endometrial cancer. Along with the evidence, the mechanism that shows excessive weight
causing cancer is discussed in the article. It is found that alteration of the hormonal system and
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chronic inflammation by obesity are the main reason behind introducing cancer.
Figure 1: Different types of cancer caused by obesity
Source: Sung et al. (2018)
It has been noticed that most of the journal articles have supported the claim that is obesity is
associated with different types of cancer. For instance- Arnold et al. (2016) in their article
"Obesity and Cancer" has indicated the impact of high body weight on cancer as well the future
burden of this issue globally. The research has found that people with obesity have a 22% higher
chance of getting cancer at a certain age compared to people with normal weight. The occurrence
of co-morbidities and the prognosis performance factor of obese people indicate that excessive
body weight is associated with cancer. For instance- in breast cancer, most of the patients are
suffered from comorbid conditions which are noticed among obese people. However, the article
states that there is potentiality to control BMI index globally in future.
The article "Body Fatness and Cancer" produced by IARC group have summarized different
epidemiologic studies that support the link between obesity and cancer risks (Lauby-Secretan et
al. 2016). According to this article, there are eight types of cancers which are mainly associated
with BMI including colon, gastric cardia, rectum, liver, pancreas, gallbladder, breast and kidney
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cancer. Evidence has shown BMI rate higher than 40 have the maximum chance of getting
affected with these cancers. It is also cited that, the body-weight gain during adulthood is
associated with postmenopausal breast cancer. Similarly, the findings of Font-Burgada et al.
(2016) have highlighted the systematic mechanisms of how obesity can impact on cancer risk.
The article states that obesity can affect different tissues in the body that simultaneously increase
insulin, glucose, NEFA, leptin and reduce the level of adiponectin. According to this article,
these tissue imbalances directly promote the survival of cancer cells, malignant progression and
proliferation. Especially in the colon, excessive body mass can drive the composition of
microbiota which can increase local inflammation. The result of such inflammation can be
insulin resistance in the liver causing liver cancer and death. Therefore, from epidemiological
perspective, obesity is directly associated with cancer risks according to this research (Goodwin
and Stambolic, 2015).
.
Figure 2: Mechanism of obesity affecting cancer
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(Source: Font-Burgada et al. 2016)
Furthermore, the findings from NHS (National Health Service) have indicated the growing rates
of cancer in the UK due to obesity. In a recent article by NHS has claimed that 11 types of
cancers are now linked with excessive body weight among the citizens in the country (Nhs.uk,
2019). The organization has conducted 12 studies among the patients in different hospitals in the
country and found strong evidence regarding this issue. The article claimed that an increase of
5Kg/m2 BMI increases 9% chance of colorectal cancer risk in men. It also increases 56% chance
of biliary tract cancer among. 5kg of weight gain during adulthood increases chances of breast
cancer among women by 11%.
Similarly, findings from NCBI have addressed the role of obesity in cancer risks. Arendt and
Kuperwasser (2015) in their research discovered that obesity boosts chances of cancer risks. In
relation to breast cancer, obesity can put systematic changes in the circulation of insulin within
the breast microenvironment and promotes the progression of cancer cells. The increased
secretion of adipocyte-related hormones and reduced secretion of adiponectin is a key reason
behind breast tumour. Onstad et al. (2016) have also researched on the cancer risk among
women due to excessive body weights. According to this journal, obesity is more associated with
the increased rate of endometrial cancer among women. It is noticed that 57% of endometrial
cancers are associated with obesity. According to the cancer research, women with higher than
40Kg/m2 BMI has higher chances of getting affected with cancer and it has a negative impact on
mortality as well. It is assumed that reports of endometrial cancer will reach more than 42 crores
cases per 100,000 women by 2030. In spite of such massive concern, there is a limited amount of
awareness among women. A recent survey by NCBI has shown that 58% of participants are not
aware of the fact that rapid weight gain can cause cancer in future. The means, these subjects of
the area needs further researches to increase awareness among people.
Researches which doesn't support the fact
Along with the above findings, there are some researches who oppose the fact that obesity may
not be the main reason behind cancers. However the number of such researches relatively low.
Few researchers claim that people having obesity can avoid cancer risk. Journal by Campbell
(2014) states that it the most avoidable cause of cancer. An increase of 1Kg/m2 BMI may not
cause death to the people. It can have an impact on different other health hazards such as thyroid.
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However, the increase of such amount has a low impact on the local mechanisms and survival of
cancer cells. Most of the evidence shows that a BMI increase by 5Kg/m2 is most dangerous to
the progress of cancer. However, such an excessive BMI rate cannot cause every type of cancer.
Weight gain lesser than that can cause cancer up to a certain stage which is controllable. There
are some evidence which indicates excessive weights and cancer survival. The most common
evidence is available regarding the survival of breast cancer. Although the rate of weight gaining
is higher among women, it has a lesser impact on breast cancer (Renehan and Soerjomataram,
2016). 82 studies have indicated that the association between obesity and cancer risk are poorer
in the case of breast cancer. There are some studies which show that excessive body weights
have a positive outcome related to some cancer types such as lung, kidney and esophagus. That
means, the possibility of the reverse the better outcomes because of obesity cannot be ignored.
Furthermore, it has been identified excessive weight gain can be associated with cancer only if it
is gained during adulthood. The researchers who think that cancer caused by obesity is avoidable
have recommended various types of prevention mechanisms. Considering globally, many of the
countries have taken initiatives to improve diet and a healthy lifestyle among the citizens
(Cancerresearchuk.org, 2016). Especially the UK government has been reviewing unhealthy
food and the lifestyle of citizens to control the rates of cancers.
Type of Evidence being shown
It can be noticed from the above discussion that a number of evidence are used to provide
support to the statements. The evidences are mainly the survey results conducted among cancer
patients in various hospitals. Organizations like NHS, IARC, and NCBI has conducted a number
of surveys to investigate the association between obesity and cancer risks. Evidence from UK
citizens found by NHS is also provided in the discussion. It is noticed that the survey result
indicates the growing rates of cancer risk among men, women, different regions and other
demographic provides. Few results are found which shows better outcome of obesity to some
specific types of cancer. That means
Research Process
The researcher has conducted an online search to collect practical evidence related to the
relationship between obesity and cancer risk. Mainly secondary resources such as journal, online
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article and websites are accessed to conduct the research. It is noticed that secondary research
method allows considering both positive and negative side of the chosen statement. It has helped
the researcher to collect information which is for and against the statement. During the research,
various types of search terms are used to find relevant articles related to obesity and cancer. Use
of proper keywords helped the researcher to choose the quality articles quickly. The date range
of the journals is also taken into account. It is ensured that the published journals are not more
than 6 years old from the current date. It has helped the researcher to find the recent evidence
related to increasing obesity rates in different countries and how it is affecting cancer risks. Each
of the journals involves findings from different survey and other researchers which are
summarized in this paper. Furthermore, it is made sure that the websites which are used to collect
information are not commercial websites. Instead, official websites of NHS, NCBI are accessed
to gather quality and trustworthy information. Ethical perspectives are considered while
conducting the research. It is ensured that evidence and the survey results which are provided in
the paper are accurate and true. Therefore, the study is conducted with appropriate methods and
techniques and considering research ethics.
Problems during research
It is difficult to process with an evidence-based research project without facing any problems.
The researcher in this project has faced different types of issues which need to be addressed. A
major challenge is that the researcher was unable to access a few quality journals because of its
membership requirement. Many of the websites require membership with a high amount to
access the journals. Due to lack of fund these articles were not collected by the researcher.
Another major problem which the researcher has faced is finding out the journals which oppose
the fact obesity is associated with cancer. Almost every research paper indicated that there is a
strong association between excessive weight gain and cancer risk in future. It has taken to a lot of
time for the researcher to research on this context. However, few articles are found which show
evidence of better cancer results due to obesity. Furthermore, due to lack of time, various aspect
of this topic is less emphasized in this paper. For instance- the global aspects of the issue as
found in the chosen article, how cancer can be avoidable by obese people, focus on the UK
context is limited in this essay.
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Conclusion
It can be concluded from this paper that, obesity or excessive body weight can be key reason of
different types of cancers. Therefore, the researcher supports the claim that obesity and cancer
risk are associated with each other. The study has provided evidences from the chosen article
which shows that obesity rate is growing globally and it has become a major concern for cancers.
The chosen case scenario mentions that, BMI is a useful unit to measure body mass and evaluate
obesity. Evidence from the last three decade is shown in the article. It is found that, the cancer
rates caused by obesity are highest within the western countries such as the UK. A number of
aspects related to the subject area including the factors affecting high increase of body weight,
cancer rate among men and women and in different regions, different types of cancers are
analyzed in the essay. In relation to the topic, various other relevant journal articles and websites
are accessed to provide support to the argument. Findings from health related organizations such
as NHS are highlighted in this paper. It is found that, there are 11 types of cancers the UK
including colon cancer, kidney cancer, lung cancer, breast cancer, and gallbladder cancer and so
on. Survey results by NHS have indicated that, 5Kg/m2 BMI increase is dangerous for men and
women. Some of the findings have provided detailed insights about the epidemiological concept
behind the link between obesity and cancer.
Researchers have found that, obesity can increase insulin, glucose and various types of hormone
in the body which provides suitable environment for cancer cell. The changes in the tissue
promote the progress of cancer cells. It can be stated that, people should be aware of the concepts
of epidemiology to understand the impact of obesity to human body and cancer progression. Few
evidences are included which shows that obesity may not have a great impact on some types of
cancer such as the breast cancer. As the numbers are considerably fewer than researcher
supporting the issue, the researcher in this essay supports that, obesity and cancer is strongly
associated. Challenges which are faced by the researcher during this researcher are mentioned in
this discussion which should be considered by future researchers. There are some areas such as
positive effect of having excessive body weight on cancer outcome, how weight loss is
connected with cancer outcome needs further researches. It is recommended to the future
researchers to consider these factors and provide greater insights to this area of researcher.
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Reference List
Arendt, L.M. and Kuperwasser, C., 2015. Working stiff: How obesity boosts cancer risk. Science
translational medicine, 7(301), pp.301-302. Available at
[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4853750/] Accessed on: [16th Aprill, 2019]
Arnold, M., Leitzmann, M., Freisling, H., Bray, F., Romieu, I., Renehan, A. and Soerjomataram,
I., 2016. Obesity and cancer: an update of the global impact. Cancer epidemiology, 41, pp.8-15.
Campbell, P.T., 2014. Obesity: a certain and avoidable cause of cancer. The Lancet, 384(9945),
pp.727-728. Available at [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4491542/] Accessed
on: [16th Aprill, 2019]
Cancerresearchuk.org (2019) PUBLIC KNOWLEDGE OF THE LINK BETWEEN OBESITY
AND CANCER Available at
[https://www.cancerresearchuk.org/sites/default/files/public_knowledge_of_the_link_between_o
besity_and_cancer_final.pdf]
Font-Burgada, J., Sun, B. and Karin, M., 2016. Obesity and cancer: the oil that feeds the
flame. Cell metabolism, 23(1), pp.48-62. Available at
[https://www.sciencedirect.com/science/article/pii/S1550413115006300] Accessed on: [16th
Aprill, 2019]
Sung H, Siegel RL, Torre LA, Pearson-Stuttard J, Islami F, Fedewa SA, Goding Sauer A, Shuval
K, Gapstur SM, Jacobs EJ, Giovannucci EL, Jemal A. CA Cancer J Clin. (2018) Global patterns
in excess body weight and the associated cancer burden. 1-2.
Goodwin, P.J. and Stambolic, V., 2015. Impact of the obesity epidemic on cancer. Annual review
of medicine, 66, pp.281-296.
Lauby-Secretan, B., Scoccianti, C., Loomis, D., Grosse, Y., Bianchini, F. and Straif, K., 2016.
Body fatness and cancer—viewpoint of the IARC Working Group. New England Journal of
Medicine, 375(8), pp.794-798. Available at
[https://www.nejm.org/doi/full/10.1056/NEJMsr1606602] Accessed on: [16th Aprill, 2019]
Nhs.uk (2019) Is UK obesity fuelling an increase in 10 cancers?
<https://www.nhs.uk/news/cancer/is-uk-obesity-fuelling-an-increase-in-10-cancers/>
Nhs.uk (2019) Wide range of cancers now linked to being overweight
<https://www.nhs.uk/news/cancer/wide-range-of-cancers-now-linked-to-being-overweight/>
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