Associations between Hair Mineral Concentrations and Skeletal Muscle Mass in Korean Adults

Muscle health plays an important role in maintaining function and independence in the elderly, and some nutrients provide protection against the age-related decline of muscle strength and function. Minerals are important nutrients that may contribute to the prevention and treatment of sarcopenia, but they have not been well-studied. This study investigated whether hair mineral concentrations differ between subjects with low muscle mass (LMM) and subjects with normal muscle mass. Cross-sectional study. A total of 232 adults ≥ 20 years of age who visited the Health Promotion Center of the University Hospital in Gyeonggi-do, Republic of Korea. The data from 232 subjects were analyzed and divided into LMM and normal groups based on the appendicular skeletal muscle mass index (ASMI) (LMM was defined as ASMI < 7.0 kg/m2 in men and < 5.7 kg/m2 in women). Skeletal muscle mass was estimated using a multi-frequency bioelectrical impedance analysis (BIA) device with a body composition analyzer. Overall mean age of participants was 50.4±11.6 years (29.7% women). Subjects with LMM showed significantly lower triglyceride levels, greater high-density lipoprotein cholesterol levels, and lower body mass index (BMI), compared with subjects who had normal muscle mass. No significant differences in hair mineral concentrations were observed between subjects with LMM and subjects with normal muscle mass, with the exception of copper. Hair copper concentrations were significantly greater in subjects with LMM than in subjects with normal muscle mass after adjustment for covariates and factors (65.7±14.2 vs 33.1±4.3 µg/g, P = 0.035). These results suggest that hair mineral status may play a role in the development of LMM. Therefore, further studies with larger numbers of subjects are required to identify the effects of mineral imbalances, their relationships with sarcopenia, and the differences between subjects with LMM and subjects with normal muscle mass.