Research Paper Final Draft 2
Research Paper Final Draft 2
Research Paper Final Draft 2
Ms. Heasley
04/06/2022
IN PATIENTS WITH SEVERE OBESITY 1
Nowadays, fast food restaurants are scattered all over the United States. With the
increased number of office and remote jobs, people are not as active as before. This makes
obesity a problem that people can no longer ignore. Obesity is a BMI of 30 kg/m2 or greater. It
affects people of all ages and is linked to numerous health issues such as cardiovascular diseases,
diabetes, sleep apnea, impaired mobility, mental health problems, reproductive issues in men and
women, and cancer. The risk of developing comorbidities increases proportionally to BMI.
People with a BMI of 40 kg/m2 or higher are considered to have severe obesity, causing them to
have poorer health outcomes. However, there are ways to treat obesity and prevent the
development and progression of comorbidities. Lifestyle modification such as diet and exercise
is the most common intervention for weight loss. The goal is to consume less and burn more
calories, creating a calorie deficit, to achieve weight loss. Another intervention is bariatric
surgery, which has become increasingly popular for reducing weight. In this literature review,
the effects of lifestyle modification and bariatric surgery will be compared, and a conclusion of
Literature Review
Introduction
This paper explores the effects of lifestyle modification, specifically diet and exercise,
and bariatric surgery on weight loss and overall health. Information was obtained from
EBSCOhost, MEDLINE, CINAHL Plus, and PubMed. Nine journal articles were utilized and
IN PATIENTS WITH SEVERE OBESITY 2
reviewed. Some keywords that were used for the search are [“severe obesity” OR “morbid
obesity”] AND [“bariatric surgery” OR “metabolic surgery”] AND [“diet and exercise” OR
Exercise
Throughout history, it has been known that exercise is beneficial to human health.
Hippocrates once said, “All parts of the body, if used in moderation and exercised in labors to
which each is accustomed, become thereby healthy and well developed and age slowly; but if
they are unused and left idle, they become liable to disease, defective in growth and age
quickly.” We know more today than the ancient physicians ever did, but Hippocrates was
incredibly correct on the topic of aging. Another health-related topic, exercise, is beneficial
towards body composition. Body composition is the percentage of fat, bone, and muscle in one’s
body. It is commonly measured by body mass index (BMI), waist circumference (WC), waist-to-
hip ratio (WHR), waist-to-height ratio (WHtR), and body fat percentage (BF%)
Telomere Length
At the end of our chromosomes are non-replicating pieces of DNA known as telomeres
that protect the chromosome from damage. As the chromosomes divide the telomeres become
shorter and shorter eventually reaching a point where the cell can no longer divide leading to
In a 2020 research article titled The effects of short-term combined exercise training on
telomere length in obese women: a prospective, interventional study, written by Brandao et al, it
is explained that “Telomere length is inversely associated with the senescence and aging process.
Parallelly, obesity can promote telomere shortening. Evidence suggests that physical activity
The study results consisted of 13 female volunteers 20-40 yrs old, BMI between 30-40
kg/m2, living a sedentary lifestyle for at least 6 months prior to the study, and who have had
regular menses. The study subjects participated in combined aerobic and strength exercises.
Brandao et al discovered “significant differences (p < 0.05) were observed in telomere length
(respectively before and after, 1.03 ± 0.04 to 1.07 ± 0.04 T/S ratio[relative amount of telomeric
DNA (T) to the beta-globin single copy gene (S)]), fat-free mass (46 ± 7 to 48 ± 5 kg), Vo2max
(35 ± 3 to 38 ± 3 ml/kg/min), and waist circumference (96 ± 8 to 90 ± 6 cm),” (para. 4). More
precisely, they discovered “we found that the 8-week combined exercise training program
increased telomere length, physical performance, and fat-free mass, while it decreased waist
circumference. Our results showed that subjects with bigger waist circumference have lower
telomere length,” (para. 24). This article shows an inverse correlation between obesity and
telomere length and would be an excellent launching point for more research regarding the
reduction is not the only benefit of exercise, body composition is also shown to be affected.
Body Composition
To refresh, body composition is the percentage of fat, bone, and muscle in one’s body. It
is commonly measured by body mass index, waist circumference, waist-to-hip ratio, waist-to-
height ratio, and body fat percentage. In the 2017 article “Benefits of different intensity of
aerobic exercise in modulating body composition among obese young adults: a pilot randomized
controlled trial,” authored by Chih-Hui Chiu et al, they “compare the effects of different aerobic
exercise intensities and energy expenditures on the body composition of sedentary obese college
students in Taiwan,” (para. 1). Their research subjects consisted of forty-eight, 18-26-year-old
ranging from low-intensity (LITG), middle-intensity (MITG), and high-intensity (HITG). The
results were obtained via the anthropometric measurements of body composition, blood
After the 12-week exercise regimen, the researchers compared the results between the
four groups; LITG, MITG, HITG, and the control group. They affirmed that:
At baseline, the anthropometric indices did not differ significantly among the four groups
(p > 0.05). After 12-week exercise intervention, the HITG and MITG had significantly
more changes in body weight, waist circumference (WC), waist-to-hip ratio (WHR), and
waist-to-height ratio (WHtR) than the LITG. The changes in BMI and body fat
percentage differed among all four groups (p < 0.05), (para. 3).
The authors go on to say that these results are consistent with previous studies with how high-
intensity exercise is effective with decreasing BF% and improving body composition and when
comparing low-intensity and high-intensity exercise, high-intensity exercise may reduce body
Bariatric Surgery
pharmacotherapy, bariatric surgery is the most clinically and cost-effective intervention for
weight reduction. In their study, 73.5% of patients post-bariatric surgery maintained at least a
20% reduction of their initial weight at the ten-year follow-up. This procedure is recommended
for people who are severely obese (BMI ≥ 40 kg/m2), or in people whose BMI range from 30-
39.9 kg/m2 and suffers from serious complications associated with obesity. In bariatric surgery,
the size of the stomach is reduced, thus, reducing calorie intake. There are many types of
IN PATIENTS WITH SEVERE OBESITY 5
bariatric surgery. The most common are sleeve gastrectomy (SG) and Roux-en-Y-gastric bypass
(RYGB). In SG, 80% of the stomach size is reduced. In RYGB, the stomach is divided into a
smaller upper part and a larger lower part. The small intestine is rearranged and connected to
both parts of the stomach, forming a Y-shape This results in a 90-95% reduction in the gastric
With obesity on the rise, more people are turning to bariatric surgery to lose weight. With
its increasing popularity, just how safe is bariatric surgery? Dr. Bruce M. Wolfe explained that
patients who received open gastric bypass had a 2.1% risk for mortality within the first thirty
days, whereas RYGB had a 0.2% risk. Factors that affected these statistics included smoking,
sleep apnea, DVT, immobile patients, and patients with severe obesity. Wolfe explained how the
morality and complication statists are significantly lower than the result of surgeries needed from
untreated obesity. These surgeries included coronary bypass, arthroplasty, and cholecystectomy.
Mortality rates for bariatric surgery are continuing to decrease, making it more favorable than the
et al. (2021) explained that different types of bariatric surgery affect nutritional deficiencies
differently. In SG, the absorption of iron, zinc, selenium, folate, and vitamin B12 are affected,
while RYGB has a more profound impact on the absorption of essential vitamins, minerals, and
The prevalence of anemia in RYGB is twofold within 12 months of the surgery, and such
IN PATIENTS WITH SEVERE OBESITY 6
calcium absorption, and this may even result in an increased rate of fractures, especially
two years after the surgery. This happens due to the bypass of the duodenum, which has
loss of body coordination, fatigue, constipation, anorexia, blood clotting disorder, numbness, and
hormonal disturbances. Gasmi et al. conclude that although bariatric is an effective way for
weight loss in patients with severe obesity, lifelong follow-up and nutritional monitoring are
Rapid weight loss is seen in the first few months following bariatric surgery. This is the
result of reducing the stomach size as a way to prevent overeating and high-calorie intake.
Patients are placed on a clear liquid diet post-operative. Most patients can upgrade their diet to
soft chewable foods 2-4 weeks after surgery. Luca Busetto explained in her article, the
importance for patients to follow up with a dietician post-operative to promote positive eating
behaviors. A study by Sarwer et al, (2020) selected 84 patients who had received bariatric
surgery and enrolled them in dietary counseling for a 4-month period. Sarwer’s research showed
a slight increase in weight loss, compared to patients who did not receive dietary counseling.
While there was a slight change in weight, the major finding was the patient’s attitude toward
dieting dramatically changed. These patients reported significant positive changes in eating
behaviors. Leading to the conclusion that positive diet changes following bariatric surgery will
Over the past few decades, obesity rates are increasing significantly worldwide creating a
rise in obesity-related comorbidities. In the past, doctors have encouraged conventional medical
therapies to promote weight loss. In the recent decade, more doctors are turning to bariatric
surgeries to reduce weight. As a result, multiple Korean universities and hospitals got together to
produce a multicenter retrospective cohort study. In this study, they compared long-term results
from conventional therapies to bariatric surgery. The study followed 137 obese patients over a
72.1-month period, starting in January 2008 to February 2011. Out of the 137 patients, 49
received bariatric surgery while the remaining 88 received conventional treatment. The long-
term results revealed that bariatric surgery achieved the greatest weight reduction when
compared to conventional treatment. This study revealed that bariatric surgery alone led to a
reduction in comorbidities and significant weight loss. Overall, patients who received bariatric
surgery reported better quality of life and had prolonged lives. (Park, 2019).
Obesity and type 2 diabetes go hand and hand. When an individual is diagnosed with
type 2 diabetes, physicians often give them medications to control their glucose, blood pressure,
and lipids instead of being offered proper weight loss interventions and programs. Often these
medications contribute to increased weight gain, making it harder for these individuals to lose
the weight needed for proper glycemic control. Weight loss contributes to a decrease in systolic
blood pressure, an increase in HDL, a decrease in triglycerides, and many more benefits in
“1 kg of weight gained annually over 10 years is associated with a 49% increase in risk of
developing T2DM in the subsequent 10 years. In patients with T2DM a weight loss of 5–
IN PATIENTS WITH SEVERE OBESITY 8
10% results in a 0.5% reduction in HbA1c, a 5mmHg decrease in systolic blood pressure
0.45mmol/L decrease in triglycerides. For these reasons the ADA and EASD
recommend that weight loss should be strived for in all patients who have T2DM.”
(p. 376).
Bariatric surgery paired with proper diet and exercise was found to increase remission rates of
diabetes which is defined as a return of HbA1c to less than 6.5% following an intervention that
persists for at least 3 months (Diaz, 2021). It was also found that bariatric surgery decreases the
mortality rate from type 2 diabetes, this was mainly attributed to the reduction in cardiovascular
Conclusion
In conclusion, studies seem to show that bariatric surgery is more effective in reducing
secondary comorbidities than diet and exercise alone. However, it is important to note that
bariatric surgery alone is not sufficient in reducing the secondary comorbidities that come from
obesity. Bariatric surgery must be done alongside proper dieting and exercise to gain the most
effectiveness. Without proper diet and exercise, bariatric surgery can fail and make an individual
not lose weight and therefore not have any or very little effectiveness in reducing the secondary
comorbidities that go along with obesity, so it is extremely important to make lifestyle changes
after the surgery to achieve peak effectiveness. Dietary counseling and exercise programs for
patients are important and need to be discussed before surgery and more importantly, these
programs need to be followed through with after bariatric surgery. A lot of physicians tend to
shy away from offering bariatric surgery to patients because they feel that it is too risky.
However, as noted above this is not really true due to the frequency in which these operations are
IN PATIENTS WITH SEVERE OBESITY 9
being done and the use of laparoscopic techniques. There are certain body weight requirements
that a person must meet to qualify for bariatric surgery, most being a BMI of 35-40 kg/m2 in
2014). However, updated NICE guidelines believe that the cutoff for those with comorbidities
related to obesity such as type 2 diabetes, cardiovascular diseases, etc... should be lowered to 30
kg/m2 in order to reduce the long-term effects those diseases have on the body. In light of the
data, bariatric surgery is not a solution for weight loss on its own and is important to be paired
with proper diet and exercise to obtain maximum effectiveness in weight loss and the reduction
of comorbidities that are attributed to obesity. However, when bariatric surgery is paired with
diet and exercise, it has been found to be more effective in reducing these secondary
Citations
Andrews, R. C., Chen, M. Z., & Logue, J. (2014). ‘Bariatric surgery for type 2 diabetes always
https://doi.org/10.1002/pdi.1907
Bettini, S., Belligoli, A., Fabris, R., & Busetto, L. (2020, September). Diet approach before
and after Bariatric Surgery. Reviews in endocrine & metabolic disorders. Retrieved
Brandao, C.F.C., Nonino, C.B., de Carvalho, F.G. et al. The effects of short-term combined
Cheah, S., Gao, Y., Mo, S., Rigas, G., Fisher, O., Chan, D. L., Chapman, M. G., &
Talbot, M. L. (2022). Fertility, pregnancy and post partum management after Bariatric
https://doi.org/10.5694/mja2.51373
Chiu, CH., Ko, MC., Wu, LS. et al. Benefits of different intensity of aerobic exercise in
modulating body composition among obese young adults: a pilot randomized controlled
0743-4
Diaz, D. (2021, August 30). International experts outline diabetes remission diagnosis
releases/2021/international-experts-outline-diabetes-remission-diagnosis-
criteria#:~:text=1.,of%20usual%20glucose%2Dlowering%20pharmacotherapy.
Gasmi, A., Bjørklund, G., Mujawdiya, P. K., Semenova, Y., Peana, M., Dosa, A.,
Piscopo, S., Gasmi Benahmed, A., & Costea, D. O. (2021). Micronutrients deficiences in
https://doi.org/10.1007/s00394-021-02619-8
Park, J. Y., Heo, Y., Kim, Y. J., Park, J.-M., Kim, S.-M., Park, D.-J., Lee, S. K., Han, S.-M.,
Shim, K.-W., Lee, Y. J., Lee, J. Y., & Kwon, J.-W. (2019, June). Long-term effect of
retrospective cohort study. Annals of surgical treatment and research. Retrieved March
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6543048/#:~:text=In%20the%20long%2
Dterm%2C%20bariatric,in%20morbidly%20obese%20Korean%20patients.
Wolfe, B. M., Kvach, E., & Eckel, R. H. (2016, May 27). Treatment of obesity: Weight loss
and bariatric surgery. Circulation research. Retrieved March 26, 2022, from
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4888907/