Which minerals are critical for absorption that can be affected by bypassing the duodenum and jejunum?

The answer focusing on iron and calcium addresses vital aspects of nutrient absorption that can be significantly impacted when the duodenum and jejunum are bypassed. The duodenum, the first part of the small intestine, plays a crucial role in the absorption of these minerals.

Iron absorption is heavily dependent on the presence of certain dietary factors and the acidic environment typically found in the stomach and duodenum. When this section of the intestine is bypassed, the change in pH and the reduction in the availability of certain enzymes can lead to decreased iron absorption, potentially resulting in deficiencies.

Calcium absorption similarly depends on the presence of vitamin D and is also favored in the duodenum where a more acidic environment can enhance its solubility and therefore its absorption. Bypassing this area may lead to inadequate calcium absorption, with implications for bone health and metabolism.

Both iron and calcium are essential for numerous physiological functions, including oxygen transport and bone mineralization. Their deficiencies are critical health concerns that can arise from alterations in the gastrointestinal tract, highlighting the importance of these minerals in the context of the question.