The association of smoking with the occurrence of osteoporosis has been known since several decades ago where the behavior of smoking directly reduces bone density.
Like other body cells, bone cells require free blood flow from toxins to keep them growing and regenerate optimally. Toxins that damage the heart enter the body when you smoke will slowly damage the various cells of the body, not to mention bone cells. Bone cells are damaged and easily kropos cause bone density brittle and easily porous.