Accurate nutritional anthropometric measurement is a contested domain. This paper begins by comparing and contrasting the three most common types of anthropometric methods used in NHS hospitals (Hamwi method, Body Mass Index and waist measurement). It then explores the need to adjust measurements for different social groups. Finally, it identifies the factors that contribute to fluctuations in weight. There are no universally accepted guidelines for amounts and types of food to be taken.
The World Health Organization (WHO) for example, recommends eating a wide variety of foods, cutting down on salt and sugar and increasing intake of vegetables and fruit to maintain a correct body weight (World Health Organisation, 2010). The definition of correct body weight is culturally sensitive as Dudek (2010) argues that different cultures have different tolerances for bodyweight. However, universal measurements have shown that excess body weight can accelerate type 2 diabetes, stroke, arthritis, breathing problems, and psychological disorders such as clinical depression (Laquatra, 1990).
The Hamwi method calculates calorie needs in order to prevent obesity in adults with diabetes (Hamwi, 1967). This method is sensitive to different ways fat is deposited between genders. For women, 100 pounds is allowed for the first 5ft of height and then 5 pounds are added for each additional inch. Men have a baseline of 106 pounds for the first 5ft height and then 6 pounds are added for each additional inch. Actual weight is compared with this ideal benchmark (Hamwi, 1967).
The advantage of Hamwi’s method is that, it is easy to use, optimum body weight can be calculated by without the need for spreadsheet programs. The measurement requires only gender and height (Harvey, 2006). The disadvantage of the Hamwi method is that Dr Hamwi provides no references or explanations on the scientific methodology for his formula (Hamwi, 1967). It is based purely on his experiences and the assumption that, in general, males are larger than females and is therefore inaccurate.
Body Mass Index (BMI) is based on body composition and is the international standard used by the WHO for obesity measurement (World Health Organisation Expert Committee, 1995). The BMI is more scientifically sound than the Hamwi method as BMI measurements are based on data that has been collected and published for males and females of all ages, social, economic and ethnic groups (Lustig, 2003). BMI is based on the notion that weight can affect illness and eventually mortality (Harvey, 2006).
However, BMI should be treated with caution as Greenberg claims that a one-time measurement of BMI is not an accurate measurement of potential mortality, rather average BMI measurements should be taken throughout adulthood to gain a vision of weight fluctuation between ages. Jeffreys (2003) further emphasises that overweight BMI in early adulthood (median age, 22) is ‘predictive of all-cause mortality’, but gaining weight, in mid-adulthood (median age, 38), is less strongly associated with mortality (Greenberg, 2001).
Therefore being overweight over a longer period of time has stronger implications for cardiac arrest than being overweight at a certain point in a person’s life. Both Greenberg (2001) and Jeffreys (2003) suggest that having an obese BMI score later in life is not associated with higher death rates. This calls for different BMI measurements to be made available for different age groups. In practice different BMI scales are made available for children but not for adult or geriatric groups. Lohman (1991) argues that waist measurement is a better measurement for monitoring nutrition than BMI.
In his studies he found that the risk of death for women over the age of fifty was highest for those with normal BMI, but waistlines over the 35cm. Lohman (1991) believes that large waist measurement is an indication of potential mortality in older persons but overweight/obese BMI measurements are not necessarily a risk to the patient. He proposes this theory based on the fact that waist measurements reflect the fat that accumulates around ‘the vital organs at an older age, this in turn can lead to cardiac arrest.
Lohman (1991), however, does not further break down the classification of geriatric age groups, as Kozier (1998) argues ideal weight for old people varies between 51+, 70+ and 95+. The US Department of Health and Human Services states that waist parameters should be carried out in conjunction with BMI (The US Department of Health and Human Services, 2008). My experience of working in an eating disorder unit is that both measurements are taken, however in GP surgeries I have only witnessed the use of BMI. Therefore I have not witnessed evidence of a consistent approach across the NHS on anthropometric measurement.