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Published on: May 23, 2025
Disaccharide digestion: clinical and molecular aspects
Claudia C Robayo-Torres1, Roberto Quezada-Calvillo, Buford L Nichols
1Department of Pediatrics, USDA/ARS, Children's Nutrition Research Center, Baylor College of Medicine, Houston, Texas 77030, USA.
Summary
Carbohydrate malabsorption causes digestive issues like bloating and diarrhea due to osmotic load. This review covers the clinical and molecular aspects of disaccharidase digestion, crucial for understanding sugar intolerance.
Area of Science:
- Gastroenterology
- Human Physiology
- Molecular Biology
Background:
- Dietary carbohydrates are typically absorbed in the small intestine.
- Malabsorption leads to osmotic load, causing symptoms like distention and diarrhea.
- Colonic bacteria ferment undigested carbohydrates, producing gas and fatty acids.
Purpose of the Study:
- To review the clinical manifestations of sugar intolerance.
- To explore the molecular mechanisms of disaccharidase digestion.
- To understand carbohydrate malabsorption in infants and adults.
Main Methods:
- Literature review of clinical and molecular aspects of disaccharidase digestion.
- Analysis of symptoms associated with carbohydrate malabsorption.
- Discussion of physiological processes in the small intestine and colon.
Main Results:
- Sugar intolerance presents with abdominal cramps, distention, flatulence, and diarrhea.
- Infants exhibit more severe symptoms, including dehydration.
- Malabsorbed sugars and starches can be detected in stool.
Conclusions:
- Disaccharidase digestion is key to preventing carbohydrate malabsorption.
- Understanding molecular and clinical aspects aids in managing sugar intolerance.
- Further research into disaccharidase function is warranted.
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