The Issue of Nutrition in an Aging Society.

Viewed from a global perspective, Japan is often considered a country where the progression towards a low birthrate and longevity has been prominent. In 2007, the ratio of the aged population reached 21.5%, propelling Japan into the classification of a super aging society. The long-term care insurance system in Japan was initiated in the year 2000, as a general long-term care service system for the whole society, covering the nutrition, medical care, and welfare fields. The goal of nutrition in an aged society is the extension of healthy life expectancy. The ratio of elderly citizens with malnutrition is high. Due to the loss of teeth, and a decrease in digestive and physical functions, there is often a decrease in appetite, and the inability to obtain enough nutrition for physical homeostasis is related to such conditions as frailty and the partial loss of physical functions due to sarcopenia, as well as a decrease in the quality of life (QOL). The elderly can easily fall into a state of protein and energy malnutrition (PEM), due to a variety of causes. Accordingly, it is important to adopt an appropriate approach that ensures a correct understanding of the causes of malnutrition and the special characteristics of malnutrition in the elderly.