This paper introduces the approach based on methodological individualism and progressive contextualization in human ecology and ecological anthropology. Studies of ecology and human ecology can be defined as fields of science to understand the dynamics of groups of living organisms in relation with their environment. Although it is, their methodology needs not to be always holistic or group-oriented. It is often simply difficult or less useful to define an analytical unit such as a local ecosystem. It is especially the case in human ecology, where people act beyondthe border of the local ecosystem and where the impacts of human behaviour cannot be contained within the local ecosystem. In such cases, it is rather effective to study behaviour of an individual trying to understand the causes and consequences of the behaviour in the context in which the behaviour occurred. Researchers will get information for explaining the group dynamics by repeating this procedure progressively. For example, observation of behaviour of anindividual is used methodologically for understanding the behaviour of the group of which the individual is a member. This approach became more popular in ecology and has introduced into human ecology by Vayda. The time-saving spot-check method in time allocation studies offers a good example of an entry point of this approach, as shown in this paper . The approach shares some characteristics with studies based on the individual based model, which is a more recently-progressed computer-oriented method in theoretical ecology. Collecting empirical data through field studies based on methodological individualism and progressive contextualization and incorporating them into analytical models will promote further understanding in human ecology.
One hundred and sixteen community-dwelling premenoposal women aged 35-49 in Inner Mongolia (36 from a city, 39 from a farming village and 41 from a grassland community) were recruited for participation in a study to investigate osteoporosis-related factors. The bone mineral density (BMD) was measured by computed X-ray densitometry (CXD). Hand bone X-rays were taken with an aluminum step-wedge ruler. Anthropometric and several lifestyle data, including workload, exercise, milk drinking, smoking and nutrient intake, were also measured. Markers of bone metabolism, 1, 25 (OH)2D3 and fluoride in drinking water and urine samples were measured. Body height and grip strength were the highest in the city subjects. There were no significant differences in body weight and body mass index (BMI) among the three groups. The percentage of the subjects who were engaged in heavy or moderate workloads was the highest in the village subjects. The village subjects had the lowest percentages of habits of both regular exercise and milk drinking . The percentage of subjects with smoking habit was the highest in the village group. Intakes of calcium and animal protein were the lowest in the village group probably because their diets were mainly composed of grains and vegetables . For both non-dominant and dominant hands, however, the BMD of the second metacarpus were the highest in this group. Univariate logistic regression analysis demonstrated that the subjects who experienced moderate-heavy workload in their 20s and in the present time and those whose grip strength exceeded the average level had significantly higher BMD of non-dominant hand than the remainders, respectively. Multivariate stepwise logistic regression analysis also showed siginificant effects of workload and grip strength on BMD. The levels of bone-alkaline phosphatase (B-Alp) as a marker of bone formation and crosslaps (CL/Cr) as a marker of bone resorption were the highest in the grassland group. The level of 1, 25 (OH)2D3 was about 1.5 times higher in the grassland group compared with the city and village groups. Furthermore, the concentration of fluoride in drinking water and urine samples were about 5 times higher in the grassland group than other two groups . In the grassland group, concentration of fluoride in urine was positively correlated with B-Alp (r=0.34, p<0.05) and CL/Cr (r=0.39, p<0.05), respectively. These findings suggest that high workload and grip strength play important roles on BMD among women living in farming village of Inner Mongolia. Despite higher milk intake, the biological markers of bone metabolism among the grassland subjects showed postmenopausal pattern, suggesting the effects of high fluoride level in drinking water.
In this study, the 2-years changes in bone mineral density (BMD) and lifestyle for Japanese women in thirties, 127 in number, were evaluated to investigate the influence of lifestyle on BMD. The major results were as follows. 1. The subject women whose bone density was higher tended to have experienced menarche in early ages and physical exercise more frequently. 2. Two thirds of the subject women reduced BMD during 2 years, although the women having lower BMD at the 1st-year measurement showed lower reduction of BMD and increased exercise and intake of Ca-contained medicines. 3. The women who increased BMD during 2 years took more calcium-rich foods, e.g. "milk and dairy product" hand "green and yellow vegetables". 4. The health examination and service about BMD was useful to improve lifestyle for women whose BMD was lower. These findings evidence changeable BMD of women in thirties according to lifestyle against the previous supposition that it was scarcely changed. Good nutritional status caused by adequate calcium intake in particular triggers increase of BMD. In this concern, health examination and service about BMD is beneficial to women for increasing awareness of their BMD and motivation of changing their lifestyle.
Recently, economically independent elderly persons who live alone have increased in cities. Their health and/or social conditions have scarcely been studied, though the social needs such as primary care for them have increased. In order to clarify the relationship between elderly people's lifestyle and their dietary habits, we surveyed 62 elderly female volunteers living in Yokohama, using the conventional lifestyle questionnaire and the self-weighed method for foods consumed. The results obtained were as follows. 1. Food intake of the subject elderly women living alone was slightly smaller in amounts of foods taken, with large variations among them. 2. Three factors were found to be related to the elderly people's lifestyle by factor analysis. These factors, which differed from those in the Japanese National Nutrition Survey, were the subjects' economic status, staple food intake, and side-dish intake. 3. Regarding the relationship between the scores for three factors obtained by factor analysis and the subjects' lifestyle, it was clarified that the first factor, which represented the subjects'economic status, was strongly related to their lifestyle.