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What is nutrition and how will you assess it ?

The state of nutrition depends mainly on the distribution of adipose tissue in the body.Based on nutrititonal status people are classified as 
Normal weight
• Underweight
• Overweight
• Obese
How will you assess the state of nutrition at bed side?
1.Ideal body weight (IBW)
Ideal body weight (IBW) = 22.5 x (height in metres)2
In females, the ideal body weight is calculated as = 0.94 x 22.5 x (height in metres)2
If the body weight is more than 10% of IBW the person is overweight.
If the body weight (IBW) is more than 20% the individual is said to be obese.
2.Body mass index
BMI is calculated as follows.
Weight in kg/(height in metres)2
Thc normal range of BMI is 19-25
In males, it is 20-25 '
In females, it is 18-23
If BMI is between 25 and 30, the individual is overweight
If BMI is more than 30 individual is obese.
How to Grade Obesity based on BMI
Grade I  - if BMI 25-30 (over weight)
Grade II  -  if BMI 30-40 (obese)
Grade III - if BMI > 40 (very ohese)
3.Measurement of subcutaneous fat
The amount of subcutaneous fat can be estimated by measuring the skinfold thickness over the triceps.biceps,subscapular region and suprailiac region by special pair of calipers(Harpendencalliper). Equations and normograms  can be used  for conversion of skin fold thickness to bodyfat.
Subcutaneous fat is assessed by picking up the skinfold  between the indexfinger and thumb.
Normal triceps skin fold thickness adult males 12.5mm
Normal triceps skin fold thickness adult females 16.5mm
4.Bulk of musle mass  
Muscle mass can be measured with a tape. Usually mid arm circumference or mid-thigh circumference is taken from the elbow or knee joint respectively (i.e. from a fixed bony pointl
In the presence of generalised odema (anasarca) the nutrition cannot be properly assessed. 
Skinfold thickness in the midtriceps region (midway between acromion and elecranon process, when the arms are hanging by the side of the body) is the most commonly used method.Othernsites examined are biceps, infrascapular and supraiiac region.
4.BROCAS index 
Rough calculation of body weight can be obtained with Brocas index.
To use Brocas index the height of the person  should be > 100 cm, hence it is possible in adults only.
Height in  cm - 100 = desired body weight in kg
Height in inches = body weight (in kg).
5.Signs of vitamin and mineral deficiency
Search for the signs of glossitis ,chelitis ,angularstomatitis,Xerophthalmia,bitots spots and koilonychia which indicate underlying nvitamin and mineral deficiency