日本人学童の骨密度と栄養摂取状態に関する研究

抄録

For the purpose of evaluating the relationship between hone density and nutritional status in Japanese children, bone density measurements were made on urban and rural children aged 6 to 15 years and individual dietary surveys were conducted on rural children. Bone density was measured at the phalanx 5-2 center by the X-ray densitometric method. The film exposure conditions using a soft X-ray instrument were 45KVP, 5-10mAS according to the growth stage and 35cm focal distance. As a reference wedge, ivory was used. Bone density was calculated as a density index by the method of Williams and Mason. Bone density index is expressed as X-ray equivalent grams of ivory per cubic centimeter of bone.
The bone density index increased with age in both sexes and was higher in girls than in boys. The density indexes of rural children were significantly lower than those of urban children at each age group in both sexes. The nutrient intakes of rural children were markedly low in vitamin A, vitamin C and calcium as compared with the dietary allowances by sex and age.
When the comparison was made between Japanese and American children, the bone density values of Japanese children were slightly lower than those of American children.