Research Paper
Pages: 8 pages / 2200 words
Level: College
Language:
English (US)
Topic: VEGETARIANISM’S EFFECTS ON CARDIOVASCULAR DISEASE
Medicine and Health
Sources: 4 sources required
Description
For this assignment, find an article claiming that an intervention produces health or disease. Read the suggested literature or any other similar and use BRADFORD HILL’S CRITERIA OF CAUSATION to determine if there is enough scientific evidence to support that claim. Write your conclusions in two or three pages (excluding the title and reference page) in APA style. You can choose articles that talk about the causes of diseases, medical treatments, or complementary and alternative medicine (CAM). You will find an example written by students from previous years to have an idea of how the work should be done. Please, be aware that the job might be sent for publication if the professor considers (there is no economic profit from this publication). If you don’t want your work to be public, please, make the professor aware. For this same reason, avoid any type of plagiarism (even minimal) since we never know what the consequences could be if someone finds out in the future. Many jobs have been lost because someone found out that the person committed plagiarism at some point.
Running head: VEGETARIANISM’S EFFECTS ON CARDIOVASCULAR DISEASE
1
Please select one of these
sources
Introduction
There is an overall idea that reducing the consumption of red meat and increasing the
consumption of unprocessed food will proportionally reduce the overall risk a person has for
developing cardiovascular disease such as atherosclerosis. We will be approaching this topic by
reviewing multiple peer-reviewed research articles on the benefits of the vegetarian diet on
cardiovascular disease reduction, as well as those opposed to find no direct correlation with
VEGETARIANISM’S EFFECTS ON CARDIOVASCULAR DISEASE
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cardiovascular disease reduction and the vegetarian diet. For this research, we will be using a
combination of Pubmed, Google Scholar, EBSCO and other similar scientific scholarly search
engines to research any information that has to do with a plant based diet and cardiovascular
disease. The following articles demonstrate the best scientific evidence in regards to being in
favor or opposed to the idea that a plant based diet has an effect on cardiovascular disease.
Research papers that defend the thesis
Wang, F., Zheng, J., Yang, B., Jiang, J., Fu, Y., & Li, D. (2015). Effects of vegetarian diets
on blood lipids: A systematic review and meta‐analysis of randomized controlled
trials. Journal of the American Heart Association, 4(10).
Dyslipidemia is an important risk factor for the advancement of cardiovascular disease.
The authors of this systematic review and meta-analysis provided evidence that concluded there
is a link between vegetarian diets and effectively lowering blood concentration of cholesterol.
The study found that a reduction of the blood lipids such as total cholesterol (TC), low-density
lipoprotein cholesterol (LDL), high-density lipoprotein cholesterol (HDL), and non-density
lipoprotein cholesterol, suggesting that such diets are a useful non pharmaceutical approach to
managing specifically hypercholesterolemia, therefore reducing a person’s risk of developing
cardiovascular disease.
The American Dietetic Association (2009). Position of the american dietetic association:
Vegetarian diets. Journal of the AMERICAN DIETETIC ASSOCIATION. 109 (7),
1266-1282. https://jandonline.org/article/S0002-8223(09)00700-7/pdf.
The American Dietetic Association states that vegetarian diets are shown to decrease the
risk of cardiovascular diseases. An evidence-based review showed that vegetarian diets lower
risk of death from ischemic heart disease, cholesterol levels and blood pressure. Due to the
higher intake of fruits, vegetables, whole grains, and nuts, vegetarians consume more
phytochemicals than nonvegetarians. Phytochemicals are plant chemicals and are found in all
VEGETARIANISM’S EFFECTS ON CARDIOVASCULAR DISEASE
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edible parts of plants, fruits, vegetables, whole grains, nuts, seeds, and legumes. These
phytochemicals are shown to have protective effects as antioxidants, reducing platelet
aggregation and clotting, anti-inflammatory, and improvement of endothelial functions. There is
also claim that vegetarian diets were successfully used in the treatment of cardiovascular disease.
Dinu, M., Abbate, R., Gensini, G. F., Casini, A., & Sofi, F. (2017). Vegetarian, vegan diets
and multiple health outcomes: A systematic review with meta-analysis of
observational studies. Critical reviews in food science and nutrition, 57(17), 3640–
3649. doi:10.1080/10408398.2016.1138447
The authors of this article initiated this study to confirm the results of previous studies
that showed going on a vegetarian diet can have a beneficial effect in reducing cardiovascular
disease in patients. The study showed that there was a marked decrease in the levels of glucose,
LDL, total cholesterol and BMI in individuals that maintained vegan or vegetarians diets
compared to their omnivore counterparts. There was also a marked decrease in ischemic cardiac
disease and incidence from total cancer in these individuals. Vegan diets showed an even bigger
decrease in the prevalence of cancer than vegetarian diets did. The study overall showed that a
change to a vegetarian/vegan diet can help decrease the risk of cardiovascular disease in patients.
Dominique Ashen, M. Curr Treat Options Cardio Med (2013) 15: 735., Vegetarian
Diets in Cardiovascular Prevention
https://doi-org.db16.linccweb.org/10.1007/s11936-013-0266-1
The article discusses the major benefits of adopting a vegetarian diet and its effects on
decreasing cardiovascular disease. It supports its claims by providing results of several studies
that compare vegetarian diets to omnivore diets. One study in particular shows a 6% risk of CVD
in vegetarians compared to an 18% risk in omnivore’s; triple the risk factor. In addition, the
article covers the topics of improved overall cardiovascular health with reducing LDL
cholesterol, reduction of blood pressure and the risk of ischemic heart disease. Lastly, it covers
VEGETARIANISM’S EFFECTS ON CARDIOVASCULAR DISEASE
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deficiency that may occur in a vegetarian diet, but shows how these deficiencies may be
supplemented.
Tuso, Phillip. “A Plant-Based Diet, Atherogenesis, and Coronary Artery Disease
Prevention.” The Permanente Journal, 1 Feb. 2015, pp. 62–67,
www.ncbi.nlm.nih.gov/pmc/articles/PMC4315380/, 10.7812/tpp/14-036. Accessed 25
Jan. 2019.
There seems to be a strong correlation between coronary artery disease and our diet, the
primary research of this study is to determine the effects on a plant based diet, while minimizing
processed foods, sugars and animal based products. They base it on 3 mechanisms that food has
on our body, which are: 1) Eating foods low in salt, sugar and fat will prevent vascular
endothelial cell injury, 2) preventing the oxidation of LDL by increasing our intake of fresh fruits
and vegetables, 3) prevent macrophage activation by decreasing red meat and stress and
increasing exercise. It was found that by elevating polyphenols and lowering a proartherosclerotic metabolite called trimethylamine-N-oxide, it would promote the health of
vascular endothelial cells and prevent atherosclerotic coronary artery disease by those 3
mechanisms. Limitations to this study include the availability of certain foods to each population
as well as the varying amounts of red meat intake each person individually has. The are other
risk factors that we must take into account, such as smoking, but more research has to be done to
achieve the most accurate information.
Research papers that oppose the thesis
Ha, V., & Souza, R. J. de. (2015). “Fleshing out” the benefits of adopting a vegetarian diet.
Journal of the American Heart Association, 4(10).
The authors of this meta-analysis suggested a vegetarian diet may improve blood lipids of
an individual but discovered a potential concern with the dietary effects on high-density
lipoprotein and triglycerides. This analysis observed that the vegetarian diet has no effect on
VEGETARIANISM’S EFFECTS ON CARDIOVASCULAR DISEASE
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triglycerides and it also points out the specific concerns of the vegetarian diets significantly
reducing HDL levels which can offset previously observed health benefits. The article
furthermore suggest that the conscious addition of other vegetarian foods should be considered to
improve HDL levels.
Do Rosario, V. A., Fernandes, R., & Trindade, E. B. (2016). Vegetarian diets and gut
microbiota: important shifts in markers of metabolism and cardiovascular disease.
Nutrition reviews, 74(7), 444–454. doi:10.1093/nutrit/nuw012
The authors of this study showed that although a vegetarian diet can have certain positive
effects on patients health and reducing of various risk factors, it can also have certain negative
effects. The majority of these negative effects revolve around the changing of the natural
microbiota of the gut which evolutationarily has been predominantly based on an omnivorous
diet. Individuals on vegetarian diets have decreased levels of n-3 fatty acid, a decreased ratio of
n-6 to n-3 fatty acid and high concentrations of homocysteine. A change in the microbiota also
inhibits individuals ability to process vitamin B12 as well the diet overall contain smaller
amounts of vitamin B12 which has been shown to reduce the risk factors of cardiovascular
disease.
McEvoy, C. T., Temple, N., Woodside, J. V. (2012). Vegetarian diets, low-meat diets and
health: a review. Public Health Nutrition: 15(12), 2287–2294.
https://www.ncbi.nlm.nih.gov/pubmed/22717188.
The authors of this article state that a reduction on the risk of cardiovascular disease is
not independent to a vegetarian diet. With the reduction of red meat intake, it has been proven to
show a reduction in the risk of cardiovascular disease. There is evidence linking consumption of
high amounts of red meat increases the risk of cardiovascular disease. Though vegetarian diets
will reduce risk for cardiovascular disease, the reduction of meat alone will have similar effects.
There is no clear information to claim that the absence of meat in a vegetarian diet will reduce
VEGETARIANISM’S EFFECTS ON CARDIOVASCULAR DISEASE
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the risk of cardiovascular disease. It is unknown whether the vegetarian diet alone or a
combination of lifestyle modification and diet change is what lowers the risk of cardiovascular
disease. This article also states, that vegetarian diets can also have many adverse effects on
health such as nutrient deficiencies.
Kuchta, Agnieszka, et al. “Impact of Plant-Based Diet on Lipid Risk Factors for
Atherosclerosis.” Cardiology Journal, vol. 23, no. 2, 2016, pp. 141–8,
www.ncbi.nlm.nih.gov/pubmed/26779974/, 10.5603/CJ.a2016.0002. Accessed 8 Dec.
2019.
An important factor in the pathogenesis of atherosclerosis is due to abnormalities in our
plasma and lipoprotein metabolism. It has been seen that a high intake of saturated fats and
cholesterol is atherogenic, and our main source comes from animal fats. Thus research began to
investigate the effect of a vegan diet on the serum lipid profile, paying close attention to the HDL
in subjects without any subclinical atherosclerosis, which was measured using a carotid Doppler
ultrasound. Evidence has been found that the anti-atherogenic fractions of lipoproteins have no
effect on vegan subjects who have not had any subclinical atherosclerosis, which suggest that the
beneficial effect of a vegan diet for cardiovascular protection is hardly associated with HDL’s
protective ability. They also looked at the vascular remodeling of the carotid artery, which is a
predictive phenotype for human cardiovascular disease. Since there were no significant
differences in the measurements between carnivores and omnivores, it would also suggest the
vegan diet have no beneficial effects on atherosclerosis. We must take into account the age of
our subjects in the study, which are relatively young and well as the nutrient intake perspective
from the vegan diet.
Corinna Koebnick, Ada L. Garcia, Pieter C. Dagnelie, Carola Strassner, Jan Lindemans,
Norbert Katz, Claus Leitzmann, Ingrid Hoffmann, Long-Term Consumption of a
Raw Food Diet Is Associated with Favorable Serum LDL Cholesterol and
VEGETARIANISM’S EFFECTS ON CARDIOVASCULAR DISEASE
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Triglycerides but Also with Elevated Plasma Homocysteine and Low Serum HDL
Cholesterol in Humans, The Journal of Nutrition, Volume 135, Issue 10, October
2005, Pages 2372–2378, https://doi.org/10.1093/jn/135.10.2372
The article agrees with the long-term cardio protective effects of the vegetarian diet by
decreasing the total serum LDL. However, it highlights the counterproductive effects it can have
when B12 deficiency is present. Essentially, B12 deficiency leads to increased serum
homocysteine, which has long been associated with higher mortality from coronary heart disease
and an independent factor for developing cardiovascular disease. The study compares
vegetarians who supplemented vitamin B12 and those who did not, further supporting B12
deficiency as the primary cause for increased serum homocysteine.
RUNNING HEAD: CHIROPRACTIC MANIPULATION AND STROKE
THIS IS AN EXAMPLE OF WHAT IT
SHOULD BE LIKE
Chiropractic Manipulation and it’s Correlation to Cervical Artery Dissection
Name
Name
Name
Name
College Name
Profesor: Anonymous
1
Chiropractic Manipulation and Stroke
2
Abstract
A study in the Journal of Family Practice has suggested that patients considering
chiropractic cervical spine manipulation are at an increased risk of a potential cervical artery
dissection. The purpose of the study was to determine the frequency of patients, from a single
institution who were diagnosed with a cervical artery dissection and how viable the correlation
was, to undergoing chiropractic manipulation. Hill’s criteria for causality will be used to determine
whether this study provides sufficient evidence between the presumed cause (chiropractic cervical
manipulation) and effect (cervical artery dissection).
Keywords: chiropractic manipulation, cervical artery dissection, stroke
Chiropractic Manipulation and Stroke
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Chiropractic manipulation is a form of alternative medicine that has been used in the
medical field for some time. A recent study by the University of Illinois and the University of
Vermont, have linked cervical artery dissection with a progression to a cerebrovascular accident,
to vertebral manipulation by chiropractors. Using a retrospective chart review, they were able to
isolate patients between April 2008 and March 2012 who already had a diagnosis of cervical artery
dissection, following a recent chiropractic neck manipulation (Kennell, Daghfal, Patel, DeSanto,
Waterman & Bertino, 2017). Board certified neuroradiologist’s confirmed findings of cervical
artery dissection and stroke on magnetic resonance imaging and computerized tomography.
Follow-up information was obtained from nine patient’s, one of whom passed away, and the
remaining eight experienced residual symptoms (Kennell et al., 2017). Using Hill’s Criteria for
Causality in epidemiological studies, we will take a more in-depth look at the methodology of the
research and how it stacks up to these guidelines (Murphy 2012).
The strength of association or risk ratio presented in this particular study is low, in that
only 12 of the 141 patient cases used as test subjects simultaneously underwent recent chiropractic
cervical manipulation and experienced a cervical artery dissection (Kennell et al., 2017). The
magnitude of the sample size is not sufficiently large enough to make such a definitive claim.
Another pitfall is that in terms of reproducibility or consistency of the study, replicating these
conditions is no easy task, due to the specificity and seriousness of the condition. It would be
nearly impossible to find voluntary test subjects who would be receptive to having a
cerebrovascular accident induced via spinal manipulation. The fact that it was a retrospective
study, much of the pertinent information relied heavily on accurate and thorough medical
documentation as well as a patient’s memory recollection of events that had taken place days or
even years ago vis telephone calls (Kennell et al., 2017).
Chiropractic Manipulation and Stroke
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It is difficult to say that the study had specificity since proving causality of the
dissection only by the manipulation and elimination of other variables in the 12 patients
was not done. However, although the sample was small to have statistical significance, all
Twelve cases reported in the study who developed vertebral artery dissection were linked to
chiropractic manipulation (Kennell et al., 2017). The study did demonstrate temporality; for
instance, in 10 out of the 12 cases, symptoms of dissection were experienced immediately after
chiropractic manipulation and were confirmed by imaging studies. The other 2 cases developed
symptoms within two days and after two weeks of chiropractic manipulation, respectively (Kennell
et al., 2017). Regarding a biological gradient, there was weak evidence, in that the study only
required the patient to have complete chiropractic intervention at least once, and it did not measure
exactly how frequently these patients had cervical manipulation completed. Therefore, it could not
be stated with certainty that undergoing this kind of treatment once, a few times or several times
could lead to an arterial dissection and possible stroke.
In terms of plausibility, much of the evidence presented from the core study is supported
by another group of authors entitled “Cervical Manipulation and the Myth of Stroke” by Donald
R Murphy DC, who reaffirms the strong correlation between spinal manipulation, but this study
was conducted on a much larger scale, taking into consideration four case-control studies (Murphy,
2012). Plausibility is also supported by basic anatomy and physiology, even though the carotid
arteries are usually involved in arterial dissections, the vertebral arteries’ anatomical position
makes them prone to chiropractic manipulation dissections (Murphy, 2012). Especially between
the entry of the transverse foramen of C6 and the foramen magnum, and the transverse foramen of
C2 to the foramen magnum. In general, the vertebral artery runs through the foramina of vertebral
bodies C1 through C6. Once the artery exits the C2 transverse process, it must go over and through
Chiropractic Manipulation and Stroke
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many adjacent bony structures (Murphy, 2012). Whether the manipulations are performed by a
chiropractor, or a physical therapist, or a physician, an injury is likely to happen from sudden
maneuvers done to the neck. Chiropractors are known for sudden movements of the cervical spine,
which can easily cause an arterial dissection (Murphy, 2012).
However, the study does comply with analogy because it incorporates several other
studies that correlate cerebellar and spinal cord injuries to chiropractic manipulation. The article
states studies performed in 2003 and 2008 (Kennell et al., 2017). The 2003 study showed a 28%
connection between the chiropractic manipulation and cervical artery dissection. The 2008 study
illustrated a connection between vertebrobasilar stroke and chiropractic visits as well as primary
care physician visits (Kennell et al., 2017).
Following a close comparative assessment, this study does not comply with Hill’s criteria
for causality; it does not provide enough scientific evidence to support the claim that chiropractic
cervical manipulation causes cervical artery dissection, which in turn leads to a possible stroke.
Although it meets the criteria of temporality, plausibility, and analogy, it presents weak evidence
to support the strength of association, consistency and reproducibility, specificity, coherence, as
well as demonstrating a viable biological gradient.
Chiropractic Manipulation and Stroke
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References
Kennell, K. A., Daghfal, M. M., Patel, S. G., DeSanto, J. R., Waterman, G. S., & Bertino, R. E.
(2017). Cervical artery dissection related to chiropractic manipulation: One institution’s
experience: This study suggests that patients considering chiropractic cervical spine
manipulation should be advised of the risks of potential arterial dissection and stroke.
Journal of Family Practice, (p. 556-562) Retrieved from:
http://db16.linccweb.org/login?url=http://search.ebscohost.com/login.aspx?direct=true&d
b=a9h&AN=124918189&site=ehost-live
Murphy, D. R. (2012). Cervical Manipulation and the Myth of Stroke. Medicine & Health Rhode
Island, 95(6), 176–177. Retrieved from:
http://db16.linccweb.org/login?url=http://search.ebscohost.com/login.aspx?direct=true&d
b=a9h&AN=77470009&site=ehost-live