Survey of Different Factors Causing Obesity & Prevalence of Different Related Diseases in Obese People
SURVEY OF DIFFERENT FACTORS CAUSING OBESITY &
PREVALENCE OF DIFFERENT RELATED DISEASES IN
DEPARTMENT OF MICROBIOLOGY AND MOLECULAR GENETICS
Obesity is the medical condition in which excess of body fats are accumulated. An obese person
has the increased chances of reduced life expectancy and several other health problems. Obesity
is a multifactorial disorder and besides genetic factors, other factors that cause obesity are
environmental factors. Environmental factors that cause obesity are Dietary habits, sedentary life
style, sleeping habits, Lack of physical activities, medication and psychiatric illness. In this
study, a brief survey was conducted to understand different factors causing obesity and
prevalence of different diseases associated among 49 obese population of Punjab, Pakistan. In
majority of cases (57.14%), obesity was due to the interaction between genetic and
environmental factors. Large proportion of people (42.86%) was obese due to environmental
factors only. However, none of the cases were observed where only genetic factors were causing
Obesity refers to medical disorder in which excess of body fats are accumulated. The extra body
fats are responsible for serious health problems. An obese person has reduced life expectancy
and several other problems. A person may be considered obese if he/she has body weight 20%
more than normal or if his/her BMI (body mass index), which is obtained by dividing his/her
weight in kilogram by square of height in meters 
BMI = mass (kg)
(Height in m) 2
Obesity turns out to be major health issue during 21st
century, with increasing prevalence in
children and adults. According to WHO ( World Health Organization) , in 2005 about 1.6 billion
adults over 15+ age were obese and at least 20 million children under 5 years were overweight.
Obesity is responsible for increased risks of many diseases among which most common are
Coronary heart diseases, type II diabetes, cancers, hypertension or High blood pressure. It may
also result in high blood cholesterol levels, sleep apnea, osteoarthritis etc. such diseases
remarkably decrease life expectancy in obese people. 
Most common cause of obesity is excessive intake of food or consuming too many calories.
People eat too much than they used to and this trend is spreading worldwide. According to the
obesity society, in 1980, 14% of adult population in USA was obese and by 2000, figure reached
31%. Most of this extra food energy comes from increased consumption of carbohydrates 
as sweetened beverages and potato chips 
. Sweetened beverages consumption is the leading
cause of obesity among adults. Increased Fast food consumption has also been associated with
increase in obesity.
Lack of physical activities and leading sedentary life styles is also a major cause of obesity. With
increasing facilities of modern convenience devices like washing machines, dishwashers,
automobiles as well as Television and computers, majority of people have a sedentary life style.
As a result of limited movements and activities, fewer calories burn and it also affects activity of
certain enzymes dealing with food. For instance, physical activities keep level of insulin
balanced in the body. With lack of physical activities, unstable levels of insulin result in weight
Very few cases are caused by genes, medications and psychiatric illness. A little evidence
supports the cases where some obese people eat very little but due to slow metabolism, they gain
weight. Some cases of obesity may result from interplay between genes and environmental
factors. Different genes are involved in controlling the appetite and metabolism in body.
Polymorphisms in such genes result in predisposition to obesity when there is sufficient intake of
food energy as well. People carrying two copies of FTO gene (Fat mass and obesity associated
gene) have increased risk of obesity. 
Obesity may also be aggravated by insufficient sleep and several medications specially
antipsychotics. The risk of obesity is greater in patients with psychiatric illness. Insufficient sleep
results in hormonal changes that increase appetite. Also it is associated with leptin deficiency in
body. Smoking also has a major role in weight gain. Since smoking suppresses appetite,
decreased smoking rate increases risk of obesity. Men who quit smoking gain weight of about
4.4 kg while women gain weight of about 5 kg 
. However, little effect has been reported by
changing rates of smoking on obesity.
As already mentioned, obesity is defined by BMI, according to the definitions established by
WHO in 1997 and published in 2000, the values are listed in table below 
18.5-24.9 Normal weight
25-29.9 Over weight
30-34.9 Class I obesity
35-39.9 Class II obesity
>40 Class III obesity
Abnormally high body weight and excess of fats is associated with life threatening diseases.
Obesity is responsible for increased mortality rates. On average obesity has been found to reduce
life expectancy by 6-7 years. BMI (body mass index) of about 30-35 kg/m2
reduces by 2-4 years
whereas severe obesity (BMI >40 kg/m2
) has reduced life expectancy by at least ten years. 
Obesity associated morbidity is also of major concern. This includes combination of medical
disorders including Hypertension, diabetes mellitus type 2 and high cholesterol levels 
disorders may be directly caused by obesity or otherwise result from related common cause such
as poor diet and lack of physical activities. The strongest link of obesity is with type 2 diabetes.
Increase in body fats result in insulin resistance, hence body does not response normally to
The survey included 49 human subjects as sample having BMI greater than 30 kg/m2
was kept confidential. Out of these 49 subjects, 14 were males and 35 were females.
Table 1: Number of affected individuals with respect to different age groups and gender
Fig 1: Percentage of obese people with respect to different age groups
i) The questionnaire made for this activity contains basic information of subjects like
age, height, weight, sex, cast, occupation, marital status and smoking habits etc.
ii) After that the complete medical history including surgery of every subject was taken
in order to estimate risks of different diseases to occur in obese population.
iii) The next major concern was to know about the family history of the subjects to
evaluate the genetic pattern of obesity.
Age group Males females Total
<10 years 1 - 1
11-20 years 3 3 6
21-30 years 6 13 19
31-40 years 1 6 7
41-50 years 2 6 8
>50 years 1 7 8
14 35 49
Percentage of obese people with respect to
different age groups
iv) A compete diet plan of subjects was asked to check the impact of different food stuff
on weight gain of that subject.
v) Then psychiatric history was taken which includes questions about bulimia, anorexia,
depression and schizophrenia etc.
vi) The exercise also plays important role for obtaining healthy weight, so exercise
history was taken too.
vii) Sedentary life style and sleeping habits of subject were asked at last.
viii) The results were concluded by considering all these areas, percentages were
calculated to make tables and graphical representation.
Following results were concluded by considering all these areas, percentages were calculated and
graphs were plotted.
Following are the results on the basis of different casts.
Table 2: Number of obese individuals with respect to different casts
Cast No. of subjects
Fig 2: Number of obese individuals with respect to different casts.
Following are the results with respect to different BMI ranges.
Sr.No Class BMI Range (Kg/m2
) No. of subjects
1 Class - I 30 – 34.9 34 69.38%
2 Class - II 35 – 39.9 14 28.57%
3 Class - III >40 1 2.04%
Table 3: BMI ranges in obese people
Fig3: BMI ranges in obese people
Percentage of obesity in different casts
30 - 34.9 (69.38%)
35 - 39.9 (28.57%)
Following are the results on the basis of fluctuation in weight.
1 Yes 18 36.73%
2 No 31 63.26%
Table 4: Fluctuation of weight in obese people
Fig 4: Fluctuation of weight in obese people.
Following are the results on the basis of factors causing obesity.
Sr. no. Factors causing obesity No. of subjects Percentage of subjects
1 Genetic & environmental 28 57.14%
2 Environmental only 21 42.86%
3 Genetic only 0 0%
Table 5: Factors causing the obesity
Fluctuation in weight
Samples showing fluctuation
Samples not showing fluctuation
Fig 5: Factors causing the obesity
Following are the results of no of obese due to the interaction between genetic and
Sr. no Genetic & Environmental Factors No. of subjects Percentage of subjects
1 Genetic + sedentary 5 17.85%
2 Genetic + dietary 7 25%
3 Genetic + surgical 2 7.14%
4 Genetic + dietary + sedentary 13 46.44%
5 Genetic + sedentary + surgical 1 3.57%
Table 6: Genetic & Environmental factors causing obesity
Causative Factors of Obesity
Genetic + Environmental Factors
Environmental Factors only
Genetic Factors only (0.00 %)
Fig 6: Genetic & Environmental factors causing obesity
Following are the results of no of obese due to the environmental factors alone.
Sr. no Environmental Factors No. of obese Percentage of obese
1 Sedentary 2 9.5%
2 Dietary 2 9.5%
3 Post-pregnancy 2 9.5%
4 Sedentary + Dietary 11 52.33%
5 Sedentary + Surgical 4 19.04%
Table 7: Environmental factors causing obesity
Genetic and Environmental Factors Causing
Genetic + Sedentary (17.85%)
Fig 7: Environmental factors causing obesity
Following are the results showing prevalence of different obesity related diseases in obese.
No. of obese
Percentage of obese
No. of obese without
1 Hypertension 19 38.77% 30 61.22%
6 12.24% 43 87.75%
6 12.24% 43 87.75%
4 Heart disease 1 2.04% 48 97.95%
5 Reflux 24 48.97% 25 51.02%
6 High cholesterol 38 77.55% 11 22.44%
7 Snoring 28 57.14% 21 42.85%
13 26.53% 36 73.46%
9 Back pain 25 51.02% 24 48.97%
10 Swelling of feet 15 30.61% 34 69.38%
11 Knee pain 16 32.65% 33 67.34%
Sedentary + Dietry (52.33%)
Sedentary + Surgical (19.04%)
12 Headache 31 63.26% 21 42.85%
13 Dyspnea 24 48.97% 25 51.02%
11 22.44% 38 77.55%
15 Osteoarthritis 5 10.20% 44 89.59%
13 26.53% 22 44.89%
Table 8: Diseases related to obesity and their prevalence in obese people
Fig 8: Diseases related to obesity and their prevalence in obese people
A brief survey was conducted on different factors causing obesity and prevalence of different
diseases associated among obese population of Punjab, Pakistan. As the data was collected from
people of different age groups, casts and locality, variety of results were obtained. These results
were analyzed and graphs were plotted.
Since obesity is a multifactorial disorder, main focus of survey was to interpret the factors
causing obesity in a particular patient. When collective results of 49 people were analyzed, in
majority of cases, factors causing obesity were genetic and environmental. Out of 49, 28 people
or 57.14% people came out to be obese due to interaction between genetic and environmental
factors. Their family history helped to conclude whether the problem was due to genes and it ran
along the family or not. Environmental factors that seemed to be interplaying with genetic
factors were sedentary life styles, diet and surgical history. 46.44% (out of 57.14%) of people
were due to genetic causes, their dietary habits and sedentary life styles. Hence, supporting the
idea that genetic factors can influence the risk of obesity among people having inappropriate diet
and sedentary life styles. People with only genetic and dietary factors were lesser in number,
about 25% (out of 57.14%).
Large proportion of people about 21 out of 49 or 42.86% was obese due to environmental factors
only and no problem could be observed with genes. Their family history showed none of other
family member being obese making it clear that people were obese due to environmental factors
only. Environmental factors included variety of factors such as diet, sedentary life style,
pregnancies and surgeries. Of the 21 people, 52.33% were suffering due to diet and sedentary life
style. 9.5% people had normal diet but sedentary life style while 9.5% were obese due to diet
only. 9.5% were women suffering from obesity after births of their babies. Yet another majority
of about 19.04% suffered due to both surgeries and sedentary life styles.
However, none of the cases were observed where only genetic factors were causing obesity
alone. Hence, supporting the idea that genes can mostly show their effects when favorable
environment is present.
The dietary history of most of people showed that they often do over eating. A few had serious
eating disorder. Majority eat four times per day i.e., breakfast, lunch, snacks and supper. Most of
people used to eat on dining table and couch with support. And also most of them reported to
take water during and after meal. Large number of people reported to take soft drinks on daily
basis. Coke was the majority’s choice. A few used to take milk shakes. Some reported to eat
bakery items, mostly cakes and biscuits. Increased fast food consumption was also reported and
famous brands like KFC, Fri chicks and MacDonald’s was top of the list. Fried food like
samosas, French fries also reported to be taken by some people. Some used to take sweets once
in a week. Among salty snacks, most of the people used to eat Lays chips.
The psychiatric history of most people was clear except a few ones who were suffering from
depression and schizophrenia. Only few people reported to do exercise, majority was unable to
do exercise due to lack of time and laziness.
In sedentary life styles, most of people used to watch Television for at least 2-3 hours and spent
5-6 hours on internet. Mostly buses and cars were used as means of transport. And almost all
people reported to spend their free times watching TV or reading books.
Most people used to take normal sleep; very few had insufficient sleep during night. And
majority did not take nap during day hours.
Fluctuations in weight of obese people were also studies and analysis showed that 18 out of 49
(36.73%) patients had fluctuations in their body weights. These people reported that they tried to
control their weights but observing diets and exercising whereas, 31 out of 49 did not have any
fluctuations in weight.
According to values provided by WHO (World Health Organization), obese people were
classified into three classes. 69.38% patients lied in obesity class I with BMI range of about 30-
. 28.57% were in class II with BMI range about 35-39.9 kg/m2
and 2.05% were in
class III with BMI > 40 kg/m2
. Hence, majority of obese patients were lying in class I obesity
and very few were lying in severe obesity.
Several other disorders were associated with obesity in many people. Highest percentage of
obese people was those having high blood cholesterol level i.e, 77.55%. Snoring was the major
problem with most people (57.14%) but none of them took medication to avoid it. Reflux or
heart burn was also reported in 48.97% people. It mostly occurred after taking meal.
Hypertension appeared to be most severe problem with 38.77% people. And unexpectedly
diabetes type 2 was less common. It was reported only in 12.24 % people. Heart disease was
very less common, because majority of the patients were less than 40 years in age. Obstructive
sleep apnea was also reported in 12.24% people.
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