Where are carbohydrates mainly digested?

Where are carbohydrates mainly digested?

• A. In the stomach.
• B. In the mouth.
• C. In the large intestine.
• D. In the small intestine.

Answer: (D)

Carbohydrate digestion mainly happens in the small intestine. That’s where pancreatic amylase continues breaking down starch and where the brush-border enzymes on the enterocytes finish converting disaccharides like maltose, sucrose, and lactose into monosaccharides such as glucose, galactose, and fructose. Those simple sugars are then absorbed through the intestinal lining into the bloodstream. The mouth does begin starch digestion with salivary amylase, but the stomach’s acidic environment largely inactivates that enzyme, so digestion of carbohydrates doesn’t continue there. The large intestine doesn’t perform enzymatic carbohydrate digestion; remaining carbohydrates are mostly fermented by gut bacteria there. The small intestine’s combination of potent digestive enzymes and vast surface area from villi and microvilli makes it the primary site for both digestion and absorption of carbohydrates.

Carbohydrate digestion mainly happens in the small intestine. That’s where pancreatic amylase continues breaking down starch and where the brush-border enzymes on the enterocytes finish converting disaccharides like maltose, sucrose, and lactose into monosaccharides such as glucose, galactose, and fructose. Those simple sugars are then absorbed through the intestinal lining into the bloodstream. The mouth does begin starch digestion with salivary amylase, but the stomach’s acidic environment largely inactivates that enzyme, so digestion of carbohydrates doesn’t continue there. The large intestine doesn’t perform enzymatic carbohydrate digestion; remaining carbohydrates are mostly fermented by gut bacteria there. The small intestine’s combination of potent digestive enzymes and vast surface area from villi and microvilli makes it the primary site for both digestion and absorption of carbohydrates.