Mechanisms of nutrient absorption and malabsorption
- Joel B Mason, MD
Joel B Mason, MD
- Professor of Medicine and Nutrition
- Tufts University Schools of Medicine and Nutrition
- USDA Human Nutrition Research Center at Tufts University
Malabsorption refers to impaired absorption of nutrients . It can result from congenital defects in the membrane transport systems of the small intestinal epithelium or from acquired defects in the epithelial absorptive surface. Another factor that can interfere with nutrient absorption is maldigestion, which is due to impaired digestion of nutrients within the intestinal lumen or at the terminal digestive site of the brush border membrane of mucosal epithelial cells.
Although malabsorption and maldigestion are pathophysiologically different, the processes underlying digestion and absorption are interdependent, so that in clinical practice, the term malabsorption has come to denote derangements in either process.
Three steps are required for normal nutrient absorption :
●Absorption into the intestinal mucosa
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