High serum 25-hydroxyvitamin D levels are associated with greater lean tissue mass and skeletal muscle mass:a cross-sectional study on young healthy Japanese women.

Studies have shown that low serum 25(OH)D levels in young women may affect not only their own health but also the health of next generation through pregnancy and childbirth. The aim of this study is to assess the serum 25(OH)D levels in young Japanese women and to determine the factors influencing the changes in their serum 25(OH)D levels. Herein, 83 healthy young Japanese women were included. Early morning fasting blood samples, habitual food intake survey, eating habits survey, and anthropometric measurements were used to analyze the relationship between the serum 25(OH)D levels and nutrient intake, intake of food groups, dietary habits, and body composition. The findings revealed that about 50% of the study participants had an adequate intake (AI) of vitamin D (8.5 µg), whereas about 88% of the study participants were vitamin D deficient and about 12% were insufficient in serum 25(OH) levels. No significant association was observed between the serum 25(OH)D levels and nutrient intake or intake of food groups. Furthermore, higher serum 25(OH)D levels were associated with higher percentages of muscle and lean tissue, indicating that regulating the serum 25(OH)D levels helps maintain muscle mass and lowers the risk of sarcopenia and locomotive syndrome. J. Med. Invest. 71 : 260-266, August, 2024.