Anthropometrical Changes in Older Taiwanese and Diet and Exercise

Abstract

The aging process involves changes in weight, height, body mass index (BMI), muscle mass, and a redistribution of body fat. These anthropometrical measures are closely related to nutrition, functional ability and health. However, most studies conducted on aging-associated anthropometrical changes so far involve Western populations. Knowledge on population-specific changes is necessary for understanding the population-related differences. This article aims to review anthropometrical changes important to geriatric nutritional assessment including weight, height, BMI, and mid arm (MAC) and calf circumferences (CC) in older Taiwanese. BMI is probably the most widely studied anthropometrical indicator but mid arm and CC have also received increasing attention in recent years. The pattern of age-associated anthropometrical changes in Taiwanese generally parallels the Western populations. BMI, an indicator of body weight relative to height, is often considered an indicator of body fatness. Currently, the World Health Organization (WHO) sets a uniform standard of BMI 25–29.9 kg/m2 for overweight and ≥30 for obesity. However, there is evidence that these thresholds may underestimate the prevalence of overweight and obesity in Taiwanese. The Department of Health of Taiwan has adopted modified thresholds of BMI 24–26.9 kg/m2 for overweight and ≥27 for obesity for Taiwanese. Similarly, because of stature differences, elderly Taiwanese appear to have different cut-points of MAC (22.5/21 cm for Taiwanese men/women vs. 21/21 cm for Western men/women) and CC (28/25 cm for Taiwanese men/women vs. 31/31 cm for Western men/women) for undernutrition. Several social, lifestyle and dietary factors have been observed to impact these indicators in older Taiwanese. Age has the strongest impact on BMI, MAC and CC. Routine physical exercise is associated with higher BMI, MAC and CC. Cigarette-smoking is associated with lower BMI and CC but not MAC. Consumption of dairy products is associated with lower BMI and MAC but not CC. Consumption of fruit is associated with greater BMI and CC but not MAC whereas consumption of tea is associated with greater BMI, MAC and CC. These anthropometrical indicators are useful nutritional and health indicators for old persons or hospitalized patients and are included in many major geriatric nutritional assessment tools. MAC and especially CC, in addition to reflecting general nutritional status, also reflect body muscle mass or the functional status in frail elderly. Understanding these aging-associated changes and the implication of these indicators as they relate to health is important to health care and support to elderly individuals.