It is known that obesity is inversely correlated with fracture risk. It remains unclear if a low muscle mass (sarcopenia) modulates the relationship between obesity and bone mass density. Twenty-seven obese women were matched for total fat mass (+/- 0.5 kg) and age (+/- 4 yrs) and divided in 3 equal groups: class II sarcopenic, class I sarcopenic, and nonsarcopenic. Body composition (DXA) and dietary intake were measured. Our results suggest that obesity may offer some protection against osteoporosis, even in sarcopenic postmenopausal women. However, further studies are needed to examine the actual implication of these results on a clinical standpoint.