Why does bone mineral density decline after bariatric surgery, specifically Roux-en-Y gastric bypass, despite calcium and vitamin D supplementation?

💡 Explanation

Bone mineral density declines because Roux-en-Y gastric bypass can cause malabsorption of minerals like calcium, even with supplementation; this limits the available mineral to rebuild bone via the bone remodeling process. Therefore, bone density decreases, rather than from hormone level changes or muscle adaptations.

• Why does long-term potentiation strengthen synaptic connections during sleep?
• A patient with pulmonary fibrosis experiences decreased arterial oxygen saturation despite supplemental oxygen. Which mechanism explains why increased inspired oxygen only partially corrects hypoxemia?
• If a patient's inflammatory response becomes chronically activated due to persistent allergen exposure, which consequence affecting the NF-κB signaling pathway is most likely?
• If a growth factor receptor in a cancer cell line mutates to bypass normal ligand-dependent activation, which consequence becomes most likely regarding cell cycle checkpoints?
• A patient with a genetic defect has impaired cytotoxic T lymphocyte (CTL) function. Why does this deficiency increase the risk of virally induced tumors?
• What distinguishes the immune response to a vaccine with an adjuvant compared to a vaccine without an adjuvant?