Osteoporosis
Advanced age and female sex are risk factors for osteoporosis, a bone disease characterized by decreased bone density. Sex hormones play an important role in bone health: levels of estrogen or testosterone seem to regulate the replacement of cells in mature bones. Eriksen et al (1988) first reported the presence of estrogen receptors in mature bones. Lower levels of sex hormones can lead to decreased bone density. The effect of lowered testosterone seems to be less severe than that of lowered estrogen. The reason for this difference is unclear: Moggs et al (2003) state that there is "no sexual dimorphism in receptor distribution" in bones.
Thomas et al (2001) found a relationship between body fat and bone mineral density (BMD) for women, but not men. However, Thomas found that bioavailable estradiol predicted BMD equally in men and women, pre- or post-menopause.
I can think of three reasons why women have a greater risk of osteoporosis, despite the fact that aging lowers sex hormones in both men and women. First, women's estrogen levels typically drop post-menopause, while men's testosterone levels decline more slowly. Second, the effect of the estrogen drop seems to be more severe. Third, women live longer. They're around more to suffer the effect. Still, with my non-standard hormone distribution, I do worry about the health of my bones. There simply isn't enough research into the long-term side effects of cross-sex hormone therapy. Dr. Nick Gorton's Medical Therapy and Health Maintenance for Transgender Men: A Guide For Health Care Providers gives a great review of what little is known.
Thomas et al (2001) found a relationship between body fat and bone mineral density (BMD) for women, but not men. However, Thomas found that bioavailable estradiol predicted BMD equally in men and women, pre- or post-menopause.
I can think of three reasons why women have a greater risk of osteoporosis, despite the fact that aging lowers sex hormones in both men and women. First, women's estrogen levels typically drop post-menopause, while men's testosterone levels decline more slowly. Second, the effect of the estrogen drop seems to be more severe. Third, women live longer. They're around more to suffer the effect. Still, with my non-standard hormone distribution, I do worry about the health of my bones. There simply isn't enough research into the long-term side effects of cross-sex hormone therapy. Dr. Nick Gorton's Medical Therapy and Health Maintenance for Transgender Men: A Guide For Health Care Providers gives a great review of what little is known.