The aim of our study was to investigate the association between nutrient factors and the osteo-sono assessment index (OSI) for calcaneus of young Japanese women. The subjects consisted of 965 young women aged from 18 to 22 years studying at the Department of Food and Nutrition at Nakamura-Gakuen University. The OSI was measured by ultrasonic bone absorptiometry. We found that age, weight, height, exercise, as well as the daily intakes of calcium, phosphorus, protein, energy and sodium were the main factors related to OSI in young women. Positive associations were observed between the OSI and the weight, exercise and daily intakes of calcium, protein and energy, whereas while negative associations were seen between the OSI and the age, height and daily intakes of phosphorus and sodium. In addition, all of these factors were also independently related to the OSI. (C) 2002 Elsevier Science Inc. All rights reserved.