What changes occur in the organic part of bone extracellular matrix with aging?

As most people age bone mass is lost to varying degrees.
This is especially true in Caucasian post- menopausal women. When a woman has her
monthly menstrual period, hormones are secreted that help maintain bone health. After
menopause these hormones are no longer being secreted into the bloodstream. Combined
with other factors like deficiencies of calcium, phosphorus, and vitamin D, the bones of
these women become brittle and porous. The bones lose mass and strength due to the loss
of intracellular and extracellular bone matrix. These women are susceptible to
spontaneous fractures.

Another reason most people lose bone
mass as they age is related to activity levels. Most (not all) people have a decrease in
physical activity levels as they age. Physical activity helps to strengthen bones and
maintain the overall health of bone tissue.