What role does estrogen deficiency play in osteoporosis development?

• A. Decreases bone resorption
• B. Has no effect
• C. Accelerates bone resorption due to increased osteoclast activity after menopause
• D. Only affects calcium absorption in the gut

Answer: (C)

Estrogen normally keeps bone remodeling in check by inhibiting osteoclast formation and activity. After menopause, estrogen levels fall, and this inhibition weakens. The balance shifts toward bone resorption because osteoblasts and other cells increase the production of RANKL relative to osteoprotegerin (OPG), promoting osteoclast differentiation and activity. More active osteoclasts break down bone faster, especially trabecular bone, leading to net bone loss and higher fracture risk. In addition, higher levels of inflammatory cytokines like IL-1, IL-6, and TNF-alpha further stimulate osteoclasts, amplifying the effect. So estrogen deficiency accelerates bone resorption due to increased osteoclast activity after menopause.