Accurate assessment of the habitual dietary intake is pre-requisite to accurate studies on diet and health, but underestimation of the dietary intake has been apparent in numerous studies. If the underestimation of dietary intake was consistent, a solution to the problem would be relatively easy, because such techniques as energy adjustment should improve estimates of the food and nutrient intake. If, however, underestimation of the dietary intake was a selective phenomenon, it would be much more difficult to solve the problem. A limited number of studies in Western countries have examined whether all foods and nutrients are underestimated to the same degree or only specific foods and/or nutrients are selectively underestimated by using the observed food intake, the measured total energy expenditure with/without 24-hour urinary nitrogen excretion, and the Goldberg cut-off technique as reference methods. These investigations are summarized in the present review. The bulk of the data from these studies suggests that when the energy intakee has been underestimated, such underestimation of the food and nutrient intake is selective rather than consistent. However, little information about those foods that are selectively underestimated is available, so further research is needed to identify such foods.
The relationship was examined between a positive perception toward work and the dietary habits of young male workers to test the reliability and validity of a working life-related “quality of life” (QOL) scale. The subjects were 473 male employees in the age range from twenties to forties working for a medical equipment manufacturing company in Tokyo. A questionnaire survey was conducted in 2001, and the results were analyzed from responses provided by 61.9% of the subjects (n=293). The questionnaire covered quality of life, health condition, behavior, attitude, environment factors, dietary habits and working life factors. Three items were selected by a principal component analysis for a “positive perception toward work”. The “positive perception toward work” was scored on the scale of 4 for three items: from the most positive=4, to the least positive=1. The total mean of the score was 8.0, and Cronbach's α-coefficient was 0.68 for reliability. High concurrent validity was found by the relationship between the “positive perception toward work” score and the dietrelated and health-related quality of life scores. A path analysis presented two courses effecting the “positive perception toward work”. One was the working life course (dietary support at the workplace→job support→“positive perception toward the work”), while the other was the dietary habits course (dietary support at workplace→food consumption, diet-related attitudes→diet-related QOL→health condition→“positive perception toward work”). The “positive perception toward the work” scale could therefore be an effective measurement of working liferelated QOL in evaluating nutrition education for young male workers.
A chronically deficient calcium intake causes defluxion of calcium from osseous tissue, while at the same time increasing the calcium concentration within cells that results in various disorders to cell functions or calcification of soft tissue. It has also been hypothesized that a deficient calcium intake promotes the migration of calcium into the nails. This study was conducted on 24 female university students to assess the effect of an increased calcium intake on the calcium concentration in the nails. Each subject was instructed to consume one pack per day of a calciumenriched food for 2 months. The calcium concentration in the fingernails and the osteo sono-assessment index (OSI) were measured before starting consumption of the calcium-enriched food (baseline) and after 2, 3 and 4 months. OSI was significantly higher after 3 and 4 months, while the fingernail calcium concentration was significantly lower after 4 months (baseline, 1.294±0.234mg/g; after 4 months, 1.089±0.197mg/g (P<0.01)). These results clearly demonstrate that the fingernail calcium concentration can be decreased by improving the calcium nutritional status, and it is suggested that measuring the fingernail calcium concentration would be useful as an indicator of the calcium nutritional status.
A qualitative research trial was performed to clarify the recognition for body-weight change and health-related behavior of adult women by a semistructured interview with a content analysis. The subjects were eight women who had given birth (44-53 years old). Three subjects had BMI of more than 25 now or in the past (obese group), two had BMI of less than 25 but tending to increase (normal weight increase group) and three were of normal weight without any tendency for increase (normal weight group). The responses of the subjects from the obese and normal weight increase groups indicated that tolerance and lack of recognition of their obesity, people concerned and the medical institution attended during pregnancy or after birth were all component factors in their weight gain. Every subject was interested in health and such health-related activities as paying attention to eating habits, but three of the five subjects in the obese and normal weight increase group did not have a regular medical checkup. We report one representative case from each group. The results show the importance of qualitative research to clarify the actual conditions and recognition of body-weight change, as well as of quantitative research to prevent and treat obesity.
The Ainu are indigenous people of Japan who have mainly resided in the Hokkaido and Tohoku regions. They have traditionally obtained starch and onturep from roots of the lily (Cardiocrinum cordatum var. glehnii) which is thought to have been their main edible plant for use as a food and medicine. We prepared starch and onturep in this study and analyzed their compositions. Starch was extracted from roots of the lily, and the remaining root materials were fermented, dried, and made into onturep. They had a high carbohydrate content. Onturep was made into gruel, the energy of the gruel for one meal being calculated to be about 240kcal. The Ainu have traditionally made dried foods high in energy level and fiber content by using starch extracted from the roots and the remaining root materials. The consumption of these dried foods has enabled the Ainu to maintain a stable and nutritious diet.