obesity symptoms, obesity causes , types of obesity ,how to prevent obesity.BMI

Hello, friends as Human civilization has reached to an ultra-advanced era where it can solve all its problems by modern means. today’s era, it is observed that goals of life are changed. Society is becoming materialistic. People are adopting unhealthy life style. Dietary habits, daily activities, earning sources all these things are changed. This unwanted & unhealthy change gives momentary happiness but left foot prints like obesity so while Treating my patients and during research work i felt to share my views with you hence before stating i want introduce you about obesity modern as well as ayurvedic view with my first two blogs.

CLASSIFICATION:obesity symptoms, obesity causes , types of obesity ,how to prevent obesity.

a. According to severity

i. Mild

ii. Moderate

iii. Severe

b. According to mode of onset:

i. Gradual

ii. Rapid

iii. Incidious

c. According to Stage of onset

i. Juvenile onset obesity

ii. Adult onset obesity

d. According to BMI( Body mass index):

Overweight BMI ≥ 25 kg/m2

Pre obese BMI 25-29.9 kg/m2

Obese class I BMI 30-34.9 kg/m2

Obese class II BMI 35-39.9 kg/m2

Obese class III BMI ≥ 40 kg/m2

e. According to surgical literature (categories of class III obesity):

i. Severe: BMI > 40 kg/m2

ii. Morbid: BMI > 40-49.9 kg/m2

iii. Super: BMI > 50 kg/m2

f. According to histopathology:

i. Hypertrophic obesity

ii. Hyper plastic obesity

iii. Combination of both

g. According to Etiological factors:

(a) Physiological – Observed temporarily during puberty, pregnancy

(b) Pathological – It is again divided into 3 viz.

(i) Exogenous – caused due to overeating & physical inactivity

(ii) Endogenous – Due to endocrine disorders i.e. Causing’s Syndrome

Hypothyroidism, Polycysctic ovarian syndrome, Hypoglyceamia, Frohlich’s

Syndrome.

(iii) Idiopathic – When every possible causative factors of obesity has been investigated and ruled out.

h. According to distribution of fat:

(a) Generalized: - Generalised accumulation of fat in the body and usually seen in exogenous obesity

(b) Central (Android Obesity):- Storage of fat mainly in the abdomen.

(c) Superior (Buffalo type):- Involving the face, neck, arms and upper part of trunk, common in Cushing’s syndrome or hypothyroidism.

(d) Inferior type: - Involving lower part of trunk and legs.

(e) Girdle type (Gynoid Obesity):- Involving hips, buttock, abdomen found in

Pituitary or hypothalamic lesions.

(f) Breaches (Trochanteric type):- Involving only the buttocks found in Hypogonadal syndrome.

(g) Lipomatous type:- Multiple Lipomatosis with localized depositions of fat over the body.

i. According to Degree of obesity:

1. Mild degree obesity: 25% excess body weight than normal.

2. Moderate degree obesity: 50% excess body weight than normal.

3. Severe degree obesity: 75% excess body weight than normal

4. Very sever degree obesity: 100% excess body weight than normal.

Measurement:

The methods of assessment of obesity are as follows:

1. BMI

2. Waist Circumference

3. Waist Hip ratio

4. Skin fold thickness ( Anthropometry )

5. Hydrometry

6. Computed tomography (CT scan) and Magnetic Resonance Image(MRI).

7. Broka’s index

 

1. BMI : ( Body Man Index )

BMI is calculate by taking an individual weight (in kg) and dividing it by his or her height (in meters square). It is inexpensive and measures an individual total weight, relative to their height.

 

Height (in m )

Weight (in kg)

 

This index provides a satisfactory measure of obesity in people who are not

hypertrophied athletes. The classification of obesity as per B.M.I:

Under weight - <18.5 kg/m2

Normal weight - 18.5 - 24.9 kg/m2

Over weight - 25 - 29.9 kg/m2

Obesity (Class-I) - 30 - 34.9 kg/m2

Obesity (Class-II) - 35 - 39.9 kg/m2

Morbid Obesity (Class-III) - > 40 kg/m2

 

2. Waist circumference:

Waist circumference measurement becomes helpful to assess the risks associated with obesity. The waist circumference is easily measured by using a simple measuring tape, which is placed at the midpoint between the lowest part of the ribs and the highest point of the iliac chest and centrally positioned 1cm below the umbilicus .

A waist circumference is > 102 cm in men and > 88 cm in female called obesity.

 

3. Waist Hip ratio:

Waist circumference is the minimum circumference between the costal margin and iliac crest, measured in the horizontal plane, with the subject standing. Hip circumference is the maximum circumference in the horizontal plane, measured over the buttocks. The ratio of the former to the latter provides an index of the proportion of intra abdominal fat.

Average value of waist hip ratio is as follow:

In men, average value is 1.

In women, average value is 0.8.

From studies, it is evident that men and women, who have a high waist/hip ratio circumference, have increased risk of death, blood pressure and serum lipid levels.

 

4. Skin fold thickness:

It is also known as Anthropometry. This method is carried out by with the help of venier caliper

The thickness of the adipose tissues which is lying in subcutaneous layer is

measured by skinfold thickness. The four most commonly site used for skinfold measurement are Biceps, Triceps, subscapular and suprailiac. The method is inexpensive, but requires a skilled observer and is not applicable to very obese people whose skinfolds would not fit between the jaws of the measuring caliper. This is not a reliable method for estimating intraabdominal fat.

 

5. Hydrometry:

Also known as underwater weighing or densitometry. In this method isotope labeled water is being used. This method is the most accurate method for assessment in the very obese (>200 kg) person, but these are unsuitable of routine practice.

 

6. Imaging Techniques –

Images of cross sections of the body can be obtained by computed tomography using either X-rays or magnetic resonance techniques in principle, the entire body can be visualized by serial transverse scans. It gives accurate results and having capacity to capture specific organ adipocity levels but very expensive and time consuming.

 

7. Broca’s index: This measurement is easy to calculate and accurate.

The formula for broka index

1)( Height in centimeters- 100= normal weight)

2)(Normal weight – 10%= ideal weight)

The broca formula, named after the inventor paul broca, a French army doctor. Paul broca had to examine military capability of young men. (Ref – encyclopaedia)

 

Fat:-

Obesity is condition in which excess deposition of fat takes place in the body. The fat also recognised as lipids. The fat present in the blood known as blood lipids and when stored in the adipose tissue known as triglyceride. Thus, the storage of excessive amount of triglycerides in the adipose tissue as body fat is responsible for Obesity. These triglycerides are derived from dietary fat along with cholesterol, phospholipids and cholesterol esterase.

This dietary fat is classified into two types:

 

Types of fat:

1. Saturated fat

2. Unsaturated fat

1. Saturated fat: A fat mainly consist of saturated fatty acid is called saturated fat. Fatty acid that contains single covalent bond between two carbon atoms of hydrocarbon chain called saturated fatty acid.

2. Unsaturated fat: A fat contain unsaturated fatty acid known as unsaturated fat. In unsaturated fatty acid, there is one or more double bond between two carbon atoms of hydrocarbon chain. Unsaturated fatty acid further classified into two types:

a. Monounsaturated fat: There is only one double between two carbon atoms of hydrocarbon chain fatty acid.

b. Polyunsaturated fat: Polyunsaturated fat contains more than one double bond between carbon atoms of hydrocarbon chain fatty acid.

 

Digestion and absorption of fat:

When fat is ingested in the form of diet, a small amount of triglyceride is digested in the stomach by lingual lipase and gastric lipase. Most of digestion occurs in the small intestine through the action of pancreatic lipase. About 80% of fat is digest by pancreatic lipase. In the presence of bile salt and lecithin, pancreatic lipase broken down triglyceride, into monoglyceride and fatty acid. These monoglycerides and fattyacids than transported by miscells from intestinal lumen to absorptive cells of intestinal mucosa, via simple diffusion. Inside absorptive cells, monoglyceride and fatty acid are recombining to form triglyceride. Along with cholesterol and phospholipids, triglycerides are coated with protein and make large spherical mass called chylomicrons .Chylomicrons are very large so they are unable to enter in blood capillaries but can enter in peripheral blood circulation through lymphatic vessels. While chylomicrons pass through blood capillaries of liver and adipose tissue, the enzyme lipoprotein lipase, present in the apical surface of capillary endothelium of hepatocytes and adipocytes, break down triglyceride in chylomicron and other lipoprotein into fatty acid and glycerol. These fatty acid and glycerol absorbed by hepatocyte and adipocyte and stored as fat in the form of triglyceride.

 

Lipoprotein:

Lipoproteins are small spherical particles produced by liver and small intestine. These particles consist of an inner core of triglycerides and other lipids, and an outer shell of protein, phospholipids and cholesterol. Lipoprotein transports some non-polar and hydrophobic lipids such as triglycerides and cholesterol in watery blood plasma. Lipoproteins are categorised and named mainly according to their density. There are four major types of lipoprotein as below:

1. Chylomicrons

2. Very low density lipoprotein

3. Low density lipoprotein

4. High density lipoprotein

 

Lipogenesis:

Synthesis of triglyceride from carbohydrate and amino acid is called lipogenesis.

1. Synthesis of triglyceride from carbohydrate:

When carbohydrate rich diet consumed in large quantity and if there is no immediate requirement for energy, it converted into glycogen and stored in the hepatocytes and skeletal muscle cells. About 75% of glycogen stored in skeletal muscle fibres and rest amount in liver cells. When liver cells and muscle cells are saturated with glycogen, additional carbohydrate in the form of glucose, transported by hepatocytes to adipose cells. In adipocyte, this glucose is used to synthesize minute amount of fatty acid and large amount of glycerol. This glycerol molecule combines with three molecules of fatty acid and forms triglyceride that is ultimately stored in the adipose cells as body fat.

2. Synthesis of triglyceride from amino acids:

During digestion, proteins are broken down into amino acids. In hepatocytes, amino acids are converted into deaminated amino acids by removal of amino group(-NH2).Certain deaminated amino acids like alanine are converted into acetyl co-A .Ultimately This acetyl co-A converted into fatty acid that can be used by hepatocytes to synthesize triglyceride.

 

Storage of fat:

Excess dietary carbohydrate, proteins, and fat converts into triglycerides and deposits in adipose tissue and liver. The fat stored in adipose tissue is called neutral fat or tissue fat. When the chylomicrons are travelling through capillaries of adipose tissue or liver, the enzyme called lipoprotein lipase hydrolysis of triglycerides of chylomicrons into free fatty acid and glycerol. Free fatty acid and glycerol enter the fat cells of adipose tissue or liver cells. Than FFA and glycerol are again converted into triglycerides and stored in these cells as body fat. The lipase also cause hydrolysis of phospholipids and release fatty acids to be stored in the fat cells.

 

Adipose tissue:

Large quantities of fat are stored in the adipose tissue in the form of triglyceride. The adipose tissue also called fat deposits, tissue fat, or body fat. Adipose tissue is loose connective tissue compose of Adipocytes.

Adipocyte: Adipocytes also known as fat cells that store triglyceride. Adipocyte stores about 80-95% of triglycerides of the entire cell volume. Triglycerides deposited inside the fat cell, are generally in liquid form.

Obesity or being overweight in humans and most animals does not depend on body weight but on the amount of body fat, to be specific, adipose tissue.

In human body, adipose tissue located as below:

a. Beneath the skin (Subcuteneus fat)

b. Around internal organs (Visceral fat)

c. In the bone merrow (Yellow bone merrow)

 

Fat depot:

Adipose tissue found in specific location of the body called fat depot or adipose depot. These depots are as below:

·          Subcuteneous layer : 50%

·          Around kidney: 12%

·          In the omenta: 10-15%

·          In genital area: 15%

·          Between muscles: 5-8%

·          Behind the eyes, In the sulci of the heart, &outside of large intestine: 5%

 

Function of adipose tissue:

1. To store energy in the form of fat.

2. To produce hormone such as leptine, resistine, cytokine and TNF alpha 1

3. 98% of total body energy reaserve as Triglycerides in adipose tissue

4. Fat serves as vehicles for fat-soluble vitamins.

5. Fat in the body supports viscera such as heart, kidney and intestine.

6. Fat beneath the skin provide insulation against heat and cold.

7. Vegetable fats are rich source of essential fatty acids, which have been used by the body for growth, for structural integrity of the cell membrane and decreased platelet adhesiveness.

8. Diets rich in EEF are effective on reduction of serum cholesterol and LDL.

9. Polyunsaturated fatty acid are precursor of prostaglandins that play major role in controlling physiological function such as vascular homeostasis, acid secretion in stomach, gastro-intestinal mortality, lung physiology and reproduction.

10. Cholesterol is essential as a component of membrane and nervous tissue and a precursor for the synthesis of steroid hormones.

thank you 

obesity symptoms, obesity causes , types of obesity ,how to prevent obesity.BMI