Factors Contributing to Obesity in Women: A Comprehensive Review

This report provides a comprehensive overview of obesity, specifically focusing on the contributing factors in women. It defines obesity and its associated health risks, including diabetes, cardiovascular diseases, and depression. The report conducts a systematic review, highlighting the roles of iron deficiency, fatigue, and abnormal sleep patterns. It explores the impact of poor iron intake, increased iron demands, and inflammation on obesity. The study further examines the relationship between fatigue, iron deficiency, and sleep patterns, emphasizing the consequences of these factors on weight loss and mental health. It also discusses the role of hepcidin in iron absorption, the effects of depression and anxiety on weight, and the importance of support systems in weight management. The report concludes by emphasizing obesity as a significant health concern linked to various physiological conditions, with fatigue and tiredness as initial symptoms.

Running head: AN OVERVIEW ON OBESITY
AN OVERVIEW ON OBESITY
Name of the Student:
Name of the University:
Author Note:

1AN OVERVIEW ON OBESITY
Introduction:
‘Obesity’ can be defined as a condition when an individual has accumulated excessive
fat in the body and the body weight of the individual is 20% higher than the normal standard
weight (Abarca-Gomez et al.2017). A person is said to be obese when the basal metabolism
rate or the BMI of the body is more than 30 (Basu et al.2013). Abdominal obesity is linked to
several complications such as Polycystic Ovarian syndrome and major cancer types such as
breast in women. (Adams et al.2014). Obesity is a perpetual process. It is the combined result
of numerous factors that include, improper diet intake, iron deficiency, lack of proper sleep,
sedentary life-style, side-effect of drugs that lead to putting on a lot of weight and intake of
food items that suppresses lipid metabolism. Studies reveal that on an average 40% of the
women population all around the world are affected with obesity (Adams et al.2013). This
report would focus on identifying and carrying out a systematic review on the major
contributors of obesity in women.
Key Words:
Fatigue, obesity, Iron-deficiency, Iron profile Index, BMI, fatigue, depression, weight loss

2AN OVERVIEW ON OBESITY
PRISMA 2009 Flow Diagram
Records identified through
database searching in Scholar
(n = 50 )
Additional records identified
through other sources like PuBMED
(n =12 )
Records after duplicates removed
(n = 32 )
Records screened
(n = 29 )
Records excluded
(n =3 )
Full-text articles assessed
for eligibility
(n = 22 )
Full-text articles excluded,
(do not meet inclusion)
(n = 20 )
Studies included in
literature review
(n =20 )
Source: As adopted by author. The inclusion characteristic involves the effect of iron
deficiency in obese adult women and the review of the iron-metabolism that regulates
hecipdin levels. The second inclusion characteristic involves the analysis of weight
loss on fatigue and motivation governing it. The exclusion characteristics mainly
included papers on obesity prevalent in women post pregnancy and papers on animal
models.
Discussion from other studies:

3AN OVERVIEW ON OBESITY
The condition of obesity only arises if the intake of calories is not proportionally balanced by
the adequate burning down of the calories. Obesity leads to increased risks of a number of
diseases that include, diabetes (type2), cardiovascular diseases, depression, cancer,
osteoarthritis and obstructive sleep apnoea. Studies reveal that, there has been an 11%
increase in the entire obese population of UK from the year 1993 to 2016 (Chang et al.2014).
The standard procedure that has been issued by the NICE to measure the degree of obesity in
people include, measuring the BMI in combination with measuring the waist circumference
and then accessing the obese condition and the health risks associated with obesity (Cole et
al.2013). Obesity in women is primarily caused due to an intake of a diet poor in iron value
(Coimbra et al.2013). The optimum haemoglobin level required in an adult female is about
14g/DL, however an average haemoglobin count of only 11g/DL has been reported in 82%
women across the globe (Coimbra et al.2013). In the worst scenario, individuals with acute
obesity problems might undergo a ‘gastric balloon surgery’ that is done either by reducing the
volume of the stomach or the length of the intestines in order to facilitate better absorption of
nutrients (Furukawa et al.2017). ‘Liposuction’ is also an approach that is prescribed as a
standard method of fat reduction to people who have developed acute obesity. This method is
highly sensitive and is only prescribed to patients who are highly overweight and by no
means of physical exercise or diet plan can lose their massive weight (Datz et al.2013). The
surgery includes removal of extra layer of fat and lipids from the skin by means of suction.
Self-reported fatigue:
Continuous feeling of exhaustion and tiredness that is not resolved even after ample
amount of rest and sleep is counted as a major symptom of obesity. Fatigue has been
attributed to be one of the initial symptoms that confirm the case of obesity (Garcia-Valdes
2015). Fatigue exerts an increased amount of negative effect that lead to poor performance
outcomes in terms of academic and work progress output. One of the consequences

4AN OVERVIEW ON OBESITY
associated with ‘fatigue’ include, difficulty of the subject in being able to carry out daily
chores or being able to comply with a regular exercise schedule or a strict diet plan.
Excessive intake of fast food and a sedentary life-style has been attributed to be one of the
major factors responsible for causing fatigue in people ranging from children (9-14) years to
adults (22-45) years (Gartner et al. 2013). Scientific studies reveal a number of factors held
responsible for the cause of the feeling of ‘fatigue’ and ‘tiredness’. The primary factors being,
‘iron-deficiency’ and ‘inadequate sleep pattern’. The further sections of the paper would
focus on establishing a relationship and trying to analyse the correlation between the iron
deficiency and the feeling of fatigue and tiredness among women.
Analyzing Iron deficiency in women:
The condition of iron deficiency is scientifically known as ‘hypoferraemia’.
Deficiency of iron is a common issue all over the world, mainly targeted towards the women
of developing nations. Current research studies reveal the existence of a relationship between
the iron deficiency and obesity through a mechanism that involves ‘hecipdin’ in the
absorption of iron in the human body (Luppino et al.2013). Iron deficiency is mediated
through hecipdin and levels of hecipdin has been reported higher in obese individuals in
comparison to normal adults, as a result of which obese individuals also exhibit clinical
inflammation (Ogden et al. 2013). It is critical to note here that rise in hecipdin levels would
lead to a lower value of absorption ratio for iron and as a result it would lead to exertion of
blunt effects on iron fortification (Orr et al.2013). The iron profile in adults is mainly
governed on the basis of three important characteristics that include, pattern of iron intake,
ability of the body to confront with increased demands and inflammation as a result of
obesity (Siddique et al.2014). The following subsections would deal with the discussion and
description of each of these factors that are pivotal in maintaining the appropriate percentage
of iron in light of the iron profile in the human body.

5AN OVERVIEW ON OBESITY
Poor Iron Intake:
Deficiency of iron is seen to have affected adults irrespective of the sex, however
documented research papers suggest that iron deficiency is the most common issue among
women. A diet deficient in iron supplements is said to be the key contributor of iron
deficiency among adult women (Simcoz and McClain 2013). It is important to note the
philosophy that operates most commonly behind the prolong intake of an iron-deficit dietary
intake among the women especially from the developing countries. Increased intake of fat-
rich food as a substitute to food items that are rich in percentage of iron in order to get instant
energy is responsible for a perpetual low iron profile in the body.
Increased Iron demand of the body:
Although, the human body is being forcibly accustomed to the intake of an iron-
deficient diet, the increased iron-demands in the body are not wiped out. As a result due to
iron starvation, the body accumulates fat and leads to the condition of being ‘obese’. Obesity
can therefore be termed as a condition that follows a cyclic manner which can be explained
stepwise as, prolong iron deficiency would lead to exhaustion and tiredness that would lead
to an aversion towards any forms of physical labour and workouts and that would eventually
lead to weight gain. Weight gain is directly proportional to inflammation which can be
concluded from the direct relationship between the increased levels of inflammation in obese
people and that would eventually lead to being overweight. Research papers indicate that Iron
deficiency can be broadly categorised under two subheadings that include, deficiency of
nutritional iron intake and functional iron deficiency (Swallen et al.2013). It has been studied
that the fat cells secrete a protein which is known as Lipocalin 2 and it sequesters the iron
stores that is that is required for the formation of haemoglobin and myoglobin that are
primarily concerned with transportation of oxygen molecule. Obesity has been reported to be
prevalent in women from increased age-groups, especially in post-menopausal women.

6AN OVERVIEW ON OBESITY
Inflammation:
Inflammation is reported to be higher in people who are obese pertaining to impaired
iron-metabolism rate rather than people with normal body weight. Obese people have
increased inflammation that is directly linked to iron deficiency. According to a research
study that was conducted on the Australian population, it was experimentally found out after
surveying both obese and non-obese people that higher basal metabolism rate reflected an
increase in value of serum ferritin and a reduction in the value of transferrin saturation.
Hence, it can be safely concluded that obesity is linked to inflammation that is an ultimate
result of iron deficiency. Iron deficiency is directly proportional to impaired duodenal iron
absorption that is primarily characterised by the reduction in the concentration of duodenal
ferroprotein and an elevated level of hepcidin concentration (Zhao et al.2015). However, in
non-obese people the iron concentration is higher which makes the metabolism process
smooth. Iron profile index varies with varying age and for an adult female between 22 to 23
years of age, the normal haemoglobin level is required to be about 14g/dL (Swallen et
al.2013).
Abnormal sleep pattern and depression:
Inadequate sleep duration and abnormal sleep patterns have resulted in tremendous
physical and mental exhaustion that have been identified with the causative agents of
frustration and stress among individuals. Lack of sleep would lead to fatigue and loss of
energy and that would not be a positive motivation for obese people to pursue extensive
physical workout sessions. It has been suggested that, obese people are prone to two types of
abnormalities pertaining to abnormal pattern of sleeping habits that include, obstructive sleep
apnoea syndrome and depression (Withrow and Alter 2013). Obstructive sleep apnoea
syndrome includes irregular sleeping habits that includes snoring and disruptive sleeping
habits characterized by frequent waking up during sleep and sleep paralysis. The disruptive
pattern of sleep is solely responsible for a rest-deprived body in obese individuals and that

7AN OVERVIEW ON OBESITY
leads to constant feelings of uneasiness and tiredness during the day. Feelings of tiredness
and fatigue leads to a reduced performance efficiency and restlessness during the daytime.
Improper sleep durations exhausts the internal body and as a result the body is unable to carry
out the routine daily chores.
Effect of weight loss on fatigue and motivation
Weight gain as well as weight loss are strongly linked to depression and anxiety.
Depression can either cause excessive weight gain or excessive weight loss, varying from
individual to individual. Depression is more prominent in adult women than in men and is
primarily caused due to social peer pressure. ‘Body-shaming’ due to being over-weight has
been a very common issue since time immemorial. Depression leads to lowering of self-
esteem among obese people and as a result the body is prone to be exhausted continuously on
the basis of extreme mental stress and exhaustion. Hence, it is inevitably important to
maintain positive thoughts as it helps in maintaining a healthy body. Strict weight-loss
workout and diet plans are drafted by dieticians and nutritionist under the supervision of a
physician in order to help lose weight. Support from family members, friends and strong
motivation from trainers can help in encouraging an obese individual to lose weight at a
faster rate. (Odgen et al.2014).
Conclusion:
‘Obesity’ has been documented to be a major concern that deals with accumulation of
extensive fat deposition in the body that ultimately impedes with the maintenance of normal
physiological conditions. The initial symptoms of obesity include feelings of exhaustion and
tiredness, however it is critical to note here that ‘obesity’ in itself is not a disorder but a
condition that is accountable to be caused due to several factors with iron deficiency being
the most pronounced one among women. Research studies reveal the association of
melanocortin-4-receptor gene to be involved with the cause of obesity however, it is has been

8AN OVERVIEW ON OBESITY
documented to be the primary cause of obesity in a few cases only. Obesity is not just caused
in one single day but is caused due to a cumulative effect exerted by factors such as intake of
iron-deficient diet, inadequate and abnormal pattern of sleep and inflammation caused due to
acute iron deficiency. Obesity is extremely common in the modern scenario pertaining to
excessive intake of junk food rich in fat substitutes and the popular sedentary life-style of the
people. However, obesity is not just a single matter of concern but is always accompanied by
a number of other factors such as hypertension, high blood sugar level, arthritis, neurological
problems and suppressed immunological response. Therefore, it is important to follow a
balanced diet plan and involve in a certain amount of physical exercise that could include
morning or evening walks, jogging or swimming. Physical exercise also helps in improving
stamina and reducing risks associated with being overweight.

9AN OVERVIEW ON OBESITY
References:
Abarca-Gómez, L., Abdeen, Z.A., Hamid, Z.A., Abu-Rmeileh, N.M., Acosta-Cazares, B.,
Acuin, C., Adams, R.J., Aekplakorn, W., Afsana, K., Aguilar-Salinas, C.A. and Agyemang,
C., 2017. Worldwide trends in body-mass index, underweight, overweight, and obesity from
1975 to 2016: a pooled analysis of 2416 population-based measurement studies in 128· 9
million children, adolescents, and adults. The Lancet, 390(10113), pp.2627-2642.
Adams, K.F., Schatzkin, A., Harris, T.B., Kipnis, V., Mouw, T., Ballard-Barbash, R.,
Hollenbeck, A. and Leitzmann, M.F., 2013. Overweight, obesity, and mortality in a large
prospective cohort of persons 50 to 71 years old. New England Journal of Medicine, 355(8),
pp.763-778.
Aigner, E., Feldman, A. and Datz, C., 2014. Obesity as an emerging risk factor for iron
deficiency. Nutrients, 6(9), pp.3587-3600.
Basu, S., McKee, M., Galea, G. and Stuckler, D., 2013. Relationship of soft drink
consumption to global overweight, obesity, and diabetes: a cross-national analysis of 75
countries. American journal of public health, 103(11), pp.2071-2077.
Chang, J.S., Chen, Y.C., Owaga, E., Palupi, K.C., Pan, W.H. and Bai, C.H., 2014. Interactive
effects of dietary fat/carbohydrate ratio and body mass index on iron deficiency anemia
among Taiwanese women. Nutrients, 6(9), pp.3929-3941.
Coimbra, S., Catarino, C. and Santos‐Silva, A., 2013. The role of adipocytes in the
modulation of iron metabolism in obesity. Obesity Reviews, 14(10), pp.771-779.

10AN OVERVIEW ON OBESITY
Cole, T.J., Bellizzi, M.C., Flegal, K.M. and Dietz, W.H., 2013. Establishing a standard
definition for child overweight and obesity worldwide: international survey. Bmj, 320(7244),
p.1240.
Datz, C., Felder, T.K., Niederseer, D. and Aigner, E., 2013. Iron homeostasis in the
metabolic syndrome. European journal of clinical investigation,43(2), pp.215-224.
Furukawa, S., Fujita, T., Shimabukuro, M., Iwaki, M., Yamada, Y., Nakajima, Y.,
Nakayama, O., Makishima, M., Matsuda, M. and Shimomura, I., 2017. Increased oxidative
stress in obesity and its impact on metabolic syndrome. The Journal of clinical investigation,
114(12), pp.1752-1761.
Garcia-Valdes, L., Campoy, C., Hayes, H., Florido, J., Rusanova, I., Miranda, M.T. and
McArdle, H.J., 2015. The impact of maternal obesity on iron status, placental transferrin
receptor expression and hepcidin expression in human pregnancy. International journal of
obesity, 39(4), p.571.
Gartner, A., Berger, J., Bour, A., El Ati, J., Traissac, P., Landais, E., El Kabbaj, S. and
Delpeuch, F., 2013. Assessment of iron deficiency in the context of the obesity epidemic:
importance of correcting serum ferritin concentrations for inflammation–. The American
journal of clinical nutrition, 98(3), pp.821-826.
Luppino, F.S., de Wit, L.M., Bouvy, P.F., Stijnen, T., Cuijpers, P., Penninx, B.W. and
Zitman, F.G., 2013. Overweight, obesity, and depression: a systematic review and meta-
analysis of longitudinal studies. Archives of general psychiatry, 67(3), pp.220-229.
Ogden, C.L., Carroll, M.D., Fryar, C.D. and Flegal, K.M., 2015. Prevalence of obesity
among adults and youth: United States, 2011-2014 (pp. 1-8). Washington, DC: US
Department of Health and Human Services, Centers for Disease Control and Prevention,
National Center for Health Statistics.

11AN OVERVIEW ON OBESITY
Ogden, C.L., Carroll, M.D., Kit, B.K. and Flegal, K.M., 2014. Prevalence of childhood and
adult obesity in the United States, 2013-2015. Jama, 311(8), pp.806-814.
Orr, J.S., Kennedy, A., Anderson-Baucum, E.K., Webb, C.D., Fordahl, S.C., Erikson, K.M.,
Zhang, Y., Etzerodt, A., Moestrup, S.K. and Hasty, A.H., 2013. Obesity alters adipose tissue
macrophage iron content and tissue iron distribution. Diabetes, p.DB_130213.
Siddique, A., Nelson, J.E., Aouizerat, B., Yeh, M.M., Kowdley, K.V. and NASH Clinical
Research Network, 2014. Iron deficiency in patients with nonalcoholic fatty liver disease is
associated with obesity, female gender, and low serum hepcidin. Clinical Gastroenterology
and Hepatology, 12(7), pp.1170-1178.
Simcox, J.A. and McClain, D.A., 2013. Iron and diabetes risk. Cell metabolism, 17(3),
pp.329-341.
Swallen, K.C., Reither, E.N., Haas, S.A. and Meier, A.M., 2013. Overweight, obesity, and
health-related quality of life among adolescents: the National Longitudinal Study of
Adolescent Health. Pediatrics, 115(2), pp.340-347.
Withrow, D. and Alter, D.A., 2013. The economic burden of obesity worldwide: a systematic
review of the direct costs of obesity. Obesity reviews, 12(2), pp.131-141.
Zhao, L., Zhang, X., Shen, Y., Fang, X., Wang, Y. and Wang, F., 2015. Obesity and iron
deficiency: a quantitative meta‐analysis. Obesity reviews, 16(12), pp.1081-1093.

12AN OVERVIEW ON OBESITY
Author,year and
country
Study-design Population Aim and
Objectives
Methodology
Abarca-Gomez
et al. 2017,U.K
Systematic-
review.
128.9 million
participants
aged 5 years
and above
Estimation of
BMI in the
world
population in
adolescents and
in children and
compare it to
the standard
adult data
Bayesian
hierarchal
model to
interpret pooled
data
Adams et
al.2013,
England
Meta-analysis 61,317
participants
(42.173 men
and 19,144
women)
To evaluate the
link of higher
BMI and
obesity to
mortal rate.
Statistical
analysis was
carried out in
order to access
and evaluate if
obesity was
influenced by
smoking and if
higher BMI had
any correlation
with an
increased
mortality.
Aigner et
al.2014,Austria
Systematic-
review
Consideration
of NHANES
population from
the database
To evaluate the
underlying
cause of obesity
as a major cause
of iron-
deficiency.
Meta-analysis
of literatures
evaluating the
condition of
hypo-ferritin
most prevalent
in adult women.
Basu et
al.2013,USA
Cross-national
analysis
Consideration
of population
across 75
countries
To evaluate the
existing
relationship
between obesity
and diabetes,
pertaining to
excessive
consumption of
aerated
beverages
Multivariate-
linear
regression
model was used
in order to
examine the
relationship
between obesity
causing diabetes
in a population
data set of 75
countries world-
wide
Chang et
al.2014,Taiwan
Systematic-
review
Evaluated the
population
strength of 25
To correlate
obesity with
reduced ferritin
Establishment
of a relationship
between obesity

13AN OVERVIEW ON OBESITY
literatures
reports
concentrations
in women
and
Hypoferremia
Coimbra et
al.2013,USA
Quantitative
analysis
Random-
sampling
To evaluate the
hecipdin
concentration in
chronic iron-
deficient adult
women
population
Quantitative
analysis of IL-6,
responsible for
regulating the
level of
hecipdin and
cause
inflammation
Datz et
al.2013,UK
Prospective-
cohort study
Evaluation of
183 adult
women affected
with chronic
anaemia
To evaluate the
strict iron
homeostasis
mechanism in
obese adult
women
Quantitative
analysis of the
iron index in
anaemic adult
women.
Furukawa et
al.2017,China
Prospective-
cohort study
Evaluation of
oxidative stress
in a sample
population size
comprising of
275 adult
women
To evaluate the
oxidative stress
governing the
iron metabolism
in adult women
Quantitative
analysis of the
factors
regulating iron-
metabolism in
obese adult
women
Garcia-Valdez
et al.2015,UK
Cross-sectional
study
Convenient
sample size of
about 75 adult
pregnant
women
To evaluate the
iron-
homeostasis
mechanism and
hecipdin
expression
during
pregnancy
Quantitative
analysis of
hecipdin
expression in
pregnant
women to judge
the iron level
concentration
Gartner et
al.2013, USA
Meta-analysis Convenient
sample size of
80 men and 115
women affected
with obesity
To access the
degree of iron-
deficiency and
cause of fatigue
in the concerned
obese
population
Statistical
analysis from
the accumulated
data sampling
Luppino et al.
2013,USA
Systematic-
review
Consideration
of a convenient
sample size of
35 obese
women
To access the
effect of obesity
and evaluate the
degree of
depression
affecting the
sample size
Qualitative
analysis with
interview
responses
Ogden et
al.2015,USA
Cross-sectional
study
Consideration
of a sample size
that included
111 obese men
and 85 obese
To evaluate the
trend of obesity
in young men
and women
Quantitative
analysis with
statistical
interpretation

14AN OVERVIEW ON OBESITY
women
Orr et
al.2013,USA
Prospective-
cohort study
Random
sampling
To access the
iron content
expression
Quantitative
analysis to
determine the
level of iron
expression by
the adipose
tissue
Siddique et
al.2014,USA
Prospective-
cohort study
Convenient
sampling
To access the
hecipdin
expression in
obese patients
with fatty liver
Quantitative
analysis to
determine the
level of
hecipdin
expression in
patients with
fatty liver
SimCox and
McClain,2013
Meta-analysis Consideration
of a population
size of 63 obese
men and 82
women
To analyse
increased
diabetes risk
pertaining to
obese
conditions
Systematic
analysis of
literature
reviews
Swallen et
al.2013,USA
Prospective-
cohort study
Consideration
of a population
sample
involving 112
men and 61
female obese
patients
To access the
depression in
relation to
obesity and
fatigue
Qualitative
analysis
involving
survey
responses
Withrow and
Alter 2013,
USA
Systematic-
review
Consideration
of a population
involving 80
female and 100
children
affected with
obesity
To access the
underlying
psychological
factors in
relation to
obesity
Qualitative
analysis using
interview
responses
Zhao et al.2013,
China
Systematic-
review
Random
sampling
To access the
effect of weight
loss in fatigue
and depression
associated with
obesity
Qualitative
analysis was
conducted using
interview
responses of the
subjects