How does the colon salvage calories?

How does the colon salvage calories?

• A. Short-chain fatty acids produced by anaerobic bacterial fermentation of undigested carbohydrates
• B. Long-chain fatty acids produced from digestion
• C. Lactic acid produced by colonocytes
• D. Amino acids absorbed from protein fermentation

Answer: (A)

Colon salvage calories primarily come from short-chain fatty acids formed when gut bacteria ferment undigested carbohydrates in the colon. These fatty acids—acetate, propionate, and butyrate—are readily absorbed by colonocytes and used as an energy source. Butyrate is especially important as the main fuel for the cells lining the colon, while acetate and propionate contribute to overall energy metabolism. This bacterial fermentation process lets the colon recoup calories from carbohydrates that escape digestion in the small intestine. Long-chain fatty acids, produced from digestion in the small intestine, are not generated by colonic fermentation. Lactic acid produced by colonocytes is not the main mechanism of caloric salvage, and amino acids from protein fermentation are not the primary source of usable energy for the host.

Colon salvage calories primarily come from short-chain fatty acids formed when gut bacteria ferment undigested carbohydrates in the colon. These fatty acids—acetate, propionate, and butyrate—are readily absorbed by colonocytes and used as an energy source. Butyrate is especially important as the main fuel for the cells lining the colon, while acetate and propionate contribute to overall energy metabolism. This bacterial fermentation process lets the colon recoup calories from carbohydrates that escape digestion in the small intestine. Long-chain fatty acids, produced from digestion in the small intestine, are not generated by colonic fermentation. Lactic acid produced by colonocytes is not the main mechanism of caloric salvage, and amino acids from protein fermentation are not the primary source of usable energy for the host.