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PROJECT REPORT

SURVEY OF DIFFERENT FACTORS CAUSING OBESITY & PREVALENCE OF DIFFERENT RELATED DISEASES IN

OBESE PEOPLE

DEPARTMENT OF MICROBIOLOGY AND MOLECULAR GENETICS

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Abstract

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 alone.

Introduction

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 [1]

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. [2]

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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 [3]

such

as sweetened beverages and potato chips [4]

. 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

gain.

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. [5]

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 [6]

. However, little effect has been reported by

changing rates of smoking on obesity.

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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 [1]

.

BMI (kg/m2) Classification

<18 underweight

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.

[7]

Obesity associated morbidity is also of major concern. This includes combination of medical

disorders including Hypertension, diabetes mellitus type 2 and high cholesterol levels [8]

. Such

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

insulin.

Materials

The survey included 49 human subjects as sample having BMI greater than 30 kg/m2 and data

was kept confidential. Out of these 49 subjects, 14 were males and 35 were females.

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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

Methods

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

2%

12%

39% 14%

17%

16%

Percentage of obese people with respect to different age groups

<10 years

age 11-20

21-30

31-40

41-50

>50

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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.

Results

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 Rajput 5

Awaan 1

Abbassi 2

Jutt 4

Syed 3

Malik 4

Butt 4

Sheikh 5

Arain 11

Qureshi 6

Mughal 4

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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 Percentage 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

10%

2% 4%

8%

6%

10%

23%

8%

8%

13% 8%

Percentage of obesity in different casts

rajputawaanabbassijuttsyedsheikharainbuttmalikqureshimughal

BMI Range

30 - 34.9 (69.38%)

35 - 39.9 (28.57%)

>40 (2.04%)

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Following are the results on the basis of fluctuation in weight.

Sr. no.

Fluctuation in weight

No. of subjects

Percentage of subjects

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(36.73%)

Samples not showing fluctuation(63.26%)

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Fig 5: Factors causing the obesity

Following are the results of no of obese due to the interaction between genetic and

environmental factors.

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(57.14%)

Environmental Factors only(42.86%)

Genetic Factors only (0.00 %)

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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%

Total 21

Table 7: Environmental factors causing obesity

Genetic and Environmental Factors Causing Obesity

Genetic + Sedentary (17.85%)

Genetic+dietary (25%)

Genetic+surgical (7.14%)

Genetic+sedentary+dietary(46.44%)

Genetic+sedentary+surgery(3.57%)

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Fig 7: Environmental factors causing obesity

Following are the results showing prevalence of different obesity related diseases in obese.

Sr.No Diseases

No. of obese carrying

associated diseases

Percentage of obese carrying associated

diseases

No. of obese without associated diseases

Percentage of obese without

associated diseases

1 Hypertension 19 38.77% 30 61.22%

2 Diabetes

mellitus 6 12.24% 43 87.75%

3 Obstructive

sleep apnea 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%

8 Arthralgia other

than knee 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%

Environmental factors

Sedentary (9.5%)

Dietry (9.5%)

Post-Pregnancy (9.5%)

Sedentary + Dietry (52.33%)

Sedentary + Surgical (19.04%)

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12 Headache 31 63.26% 21 42.85%

13 Dyspnea 24 48.97% 25 51.02%

14 Stress urinary

incontinence 11 22.44% 38 77.55%

15 Osteoarthritis 5 10.20% 44 89.59%

16 Irregular

menstrual cycle 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

Discussion

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.

0

10

20

30

40

50

60

70

80

90 Percentage ofdiseasesamong obese

Pe

rcentages

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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

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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-

34.9 kg/m2. 28.57% were in class II with BMI range about 35-39.9 kg/m

2 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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