The purpose of this study was to investigate the factors relate to trunk intramuscular fat content in younger and older men. Healthy 23 younger (20 to 29 years) and 20 older men (63 to 79 years) participated in this study. The trunk intramuscular fat content was measured using magnetic resonance imaging at the level of 3rd lumbar vertebra. Blood properties and physical performances were also measured. Dietary intake was assessed with a selfadministered diet history questionnaire. We quantified the status of the 10 nutrients intakes by summing the number of items that met the criteria of dietary reference intakes for Japanese. As a result, trunk intramuscular fat content was significantly higher in older men compared with that of younger ones (p