Increased life expectancy leads to increased prevalence of osteoporosis. When assessing body composition parameters in patients with osteoporosis, it is necessary to take into account a possible decrease in height in this group as the most frequent complication of osteoporosis against the background of vertebral compression fractures. The authors compare different methods for assessing body composition in patients with osteoporosis, because skeletal deformities and reduced height make the interpretation of body composition parameters difficult. Reduced patient height may result in overestimation of calculated measures of nutritional status using height squared in the denominator (e.g. BMI), reducing the sensitivity of these methods in assessing nutritional status. Body length measurement or anamnestic height estimation may be considered in these patients, but further research on this topic is needed. The use of densitometry or bioimpedance analysis is optimal as instrumental methods to determine body composition. Assessment of the phase angle in these patients may have additional advantages as this parameter is independent of the accuracy of anthropometric measurements. If densitometry and bioimpedance analysis are not available in these patients, indirect assessment of musculoskeletal content may have additional advantages, as this parameter is independent of the accuracy of anthropometric measurements. assessment of the musculoskeletal content of the body can be carried out by measuring the circumference of the muscles of the upper arm and lower leg of the upper arm and lower leg muscles. Densitometry or bioimpedance analysis are preferred. In addition, assessing the phase angle in such patients may have additional benefits because it is independent of the accuracy of anthropometric measurements.