Overweight is defined as when the body weight is 10% excess over the upper limit of standard weight in relation to age and sex of that individual.
Obesity is defined as when the body weight is 20% more than the upper limit of standard weight in relation to age and sex of that individual.
How will you clinically diagnosis obesity?
1) Body weight > 20% above the ideal body weight or BM1 >30.
2) When measured by a special calliper, a fat fold thickness of greater than one inch in the inferiorangle of scapula in (male) or the midtriceps region in (female) is called as obesity.
3) Ponderal index < 12 is obesity
How to diagnose obesity based on BMI?
BMI (a measure of generalised obesity) is obtained by calculating a person's weight in kilograms and dividing it by the person’s height in metres squared (kg/m2)
BMI in adults Range
Acceptable range 18.5 -24.9
Overweight 25.0 -29.9
Obese 30.0 -39.9
Morbidly obese > 40
Waist hip ratio
According to the recent evidence the regional distribution of fat may be of greater prognostic significance than the absolute degree of obesity. Abdominal or truncal obesity can be clinically measured bv ‘waist-hip ratio'.at the bedside.
The Waist hip ratio is measured by dividing the waist circumference in centimetres by the hip circumference in centimetres.
Waist circumference is measured mid-way between the superior iliac crest and the lower costalmargin in the midaxillary line. The waist is measured by taking a circumference that gives the narrowest measurement between the ribcage and the iliac crest.
Hip circumference is measured as 1 /3rd the distance between anterior superior iliac spine and the patella. The hip measurement is taken by measuring at a level that gives the maximal measurement of the hip,over the buttocks and the morbidity and mortality risk increased if the waist hip ratio > 0.95 in males or > 0.8 in females.
What are the clinical association of obesity?
- Diabetes mellitus.
- Systemic hypertension,
- Ischaemic heart disease,
- Hyperlipidaemia
- Insulin resistance may be associated with abdominal (truncal) obesity,
- Idiopathic (simple obesity).
- Physical inactivity (sedentary habit).
- Cushing’s syndrome.
- Hypothyroidism (primary).
- Hypothalamic disorders (Frochlich’s syndrome).
- Insulinoma.
- Laurence-Moon-Biedl syndrome.
- Iatrogenic — Prolonged therapy with steroid or oestrogen
1. Generalised obesity
Over eating is the most common cause
In generalised obesity there is excess fat deposition uniformly throughout the body.This is the most common type. It is characterised by the presence of a'double chin,.
2. Android obesity .It is a type of obesity, this is characterised by excess deposition of fat over the region of the waist.
3. Gynoid obesity It is a type of obesity, this is characterised by excess deposition of fat over the region of the hips and thighs.
4. Superior or central type of obesity: In this type there is excess fat deposition over face, neck and upper part of the trunk and the arms are thin. This is seen in Cushing's syndrome.
Waist-hip ratio and type of obesity and Prognosis
1.Waist-hip ratio 0.8 or less associated with Pear-shaped obesity and has Good prognosis
2.Waist-hip ratio 0.9 or greater associated with Apple-shaped obesity and has Greater risk Increased risk of developing complications of obesity