Does menopause affect lean body mass independent of the aging process?
Cross-sectional studies of women across a broad range of ages have shown an increasing rate of loss of FFM (9). In addition, Aloia et al. showed an accelerated loss of FFM with advancing age in women using more sophisticated measurements of FFM (10). They measured total body potassium (a measure of muscle mass) and total body calcium (a measure of bone mass) in 304 women of ages from 20-80 years. Both Aloia et al. and Poehlman et al. also noted a breakpoint around the time of menopause where rate of loss of FFM increased after the age of menopause. The premenopausal women lost potassium corresponding to < 0.1 kg FFM/ year whereas the postmenopausal women lost 0.7 kg FFM / year. This change in FFM and the breakpoint with age around menopause is illustrated in the figure to the right for a hypothetical woman who experiences menopause at 48 years of age [data exemplifies the mean data from the study of Poehlman et al. (10)]. Aloia et al. further noted a relationship in muscle mass and bon
