Abstract:Objective: To investigate the correlation between thyroid function within the normal range and bone mineral density as well as trabecular bone score in men of different age groups. Methods: Total of 191 men <60 years old as well as 97 men ≥60 years old, conformed to the inclusion criteria, were recruited. Free triiodothyronine (FT3), free thyroxine (FT4), thyroid stimulating hormone (TSH) and ordinary biochemistry indexes were measured. Dual energy X-ray absorptiometry (DXA) was used to measure bone mineral density (BMD) of femoral neck, total hip and lumbar spine. Trabecular bone score (TBS) was calculated with TBS iNsight software. Results: In both groups, TBS was positively correlated with BMD of each part tested. FT3 was negatively related with total hip BMD, lumbar spine BMD and TBS in young and middle-aged men. However, in elderly men, femoral neck BMD, total hip BMD and TBS were negatively related to age, which were not associated with thyroid function. Conclusion: There is a good correlation between TBS and BMD. Elevated FT3 level within the normal range was associated with bone loss and bone microstructure destruction in young and middle-aged men. In elderly men with normal thyroid function, age may have more adverse effect on bone mineral density and bone microstructure compared to thyroid function.