To assess bone mass and malnutrition according to sex, we assessed the relationship between bone mass (%YAM) and malnutrition using ultrasound imaging and the dietary variety score (DVS) in participants that attended the course on “Nutritional care for bone protection” (723 women, 74 men, mean age 74.9±5.8 years). The percentage of women without osteoporosis or pre-osteoporosis was significantly lower (10.9%) than that of men (24.3%). The average DVS was 4.9±2.0 points in women and 3.6±2.0 points in men. The DVS of participants who ate dairy products, milk, yellow-green vegetables and soybeans almost every day was high, but it was low for those who ate fish, meat and potatoes. There was a sex difference in the food group of “eat almost every day”.

The decrease in DVS could be attributed to the decrease in all types of food and not necessarily a specific food. The DVS in men was lower than that in women, and it was suggested that 25% of women and 51.4% of men were malnourished. In women, bone mass (%YAM) was a significant contributing factor of DVS after adjusting for age and BMI; however, this was not the case for men.

From these results, the pattern of dietary variety in the elderly may differ according to sex, and dietary variety may be related to bone mass and malnutrition in women, and malnutrition in men, respectively. Dietary variety and malnutrition prevention according to sex should be considered when establishing nutritional guidance for osteoporosis in the elderly.