1.1 Assessment of nutritional status
Anthropometric measurements can be considered the most commonly used methods of nutritional status, at both the individual and population levels. The measurements should characterize the composition of the human body at different degrees of nutrition under the standardized procedures and appropriate reference data. (Gibson, 2005; Willet, 1998; WHO, 1995; WHO 2000; WHO 2006). The measures of body elements assessed at individual level can be commonly used to represent individual's nutritional status directly. Furthermore, may help to distinguish between fat and fat free mass and can provide broaden information about, for example, protein store.
Additionally, in many field situations, nutritional indices can be used to classify individuals at risk of undernutrition, especially among children group.
1.2 Different anthropometric measurements and indices
Growth is an important indicator of health and nutritional status of a child and there is no single nutrition measure could be considered the best and therefore a combination of different measures is required. (Gibson, 2005; Willet, 1998; Gorstein et al, 1994; Perry et al, 2007; Maqbool et al, Gorstein, 1989)
Measures of height and weight can be considered most commonly and extensively used as a nutritional index to represent, for example, nutritional status in childhood and monitoring its changes. Anthropometric indices can usually be calculated from two or more raw combination of anthropometric indices. (WHO, 1995; WHO, 2000; WHO, 2004). Those indices are crucial for the appropriate interpretations of measures.
If in some cases, the measure of the height cannot be obtained, the use of forearm length (ulna) can calculate height according to the specific tables.
The other alternative measurements, as a knee height and demispan can also be used to estimate height. (Todorovic et al, 2003)
Moreover, the simple indices as body mass index ratio as a combination of weight and height can be used in population studies to designate obesity level at population group. The more complex combinations, such as weight-for-age, height-for-age can be used to compare the reference population data with an individual or a group and therefore can provide an evidence of malnutrition. However, their influence significantly differs on the circumstances within or across populations. (Willet, 1998; Gorstein et al, 1994; Todorovic et al, 2003)
Waist circumference measure can be reported as an indicator of visceral fat area in individuals and hence now this measure is preferred anthropometric measurement for the assessment of abdominal fat.
Mid-upper-arm muscle circumference can be used for the purpose to assess total body muscle mass as an index of protein reserves and therefore is regularly used in field surveys and in hospital practice to measure changes in muscle mass and to diagnose protein-energy malnutrition. (WHO 2000; Gibson, 2005)