We rarely use Wikipedia as a resource, but this overview on bone density is quite well done. As with any medical issue or question, please consult your physician. The Wikipedia entry is a general discussion of the topic. It is not specifically related to X and Y Chromosome Variations. For individuals who are 47,XXY, untreated hypogonadism can lead to osteoporosis and osteopenia. Most benefit from testosterone replacement therapy (TRT). Those who identify as intersex or choose not to use TRT should seek competent medical help for alternative methods to preserve bone density.