Question

vignette #1
sue and juan are newlyweds, and sue is taking a nutrition course at the local college. she wants
to apply the principles that she has learned. juan is currently a bit overweight and rarely eats a
balanced diet. sue notices that he usually has gas after meals, especially when dairy is present.
lately, he has also been complaining about constipation. lets see what you can do to assist sue
in her efforts to analyze juans digestive problems.
why might juan have gas after eating dairy products?
he eats dairy products with vegetables at the same meal.
bacteria in his colon digest the lactose, producing gas.
the lactose from the milk remains in his stomach and creates gas.
his body does not make enough sucrase to digest the dairy sugar.
his body produces too much lactase, resulting in gas formation.

Explanation:

Lactose is a sugar found in dairy products. In individuals with lactose intolerance, the small intestine does not produce enough lactase (the enzyme that breaks down lactose). As a result, undigested lactose passes into the colon. Bacteria in the colon ferment (digest) this lactose, and one of the by - products of this fermentation is gas.

• Option 1: Eating dairy with vegetables is not a known cause of gas specifically related to dairy consumption.
• Option 3: Lactose is not mainly digested in the stomach. The small intestine is the primary site for carbohydrate digestion (including lactose if lactase is present).
• Option 4: Sucrase digests sucrose (table sugar), not lactose.
• Option 5: If the body produced too much lactase, lactose would be properly digested in the small intestine, and there would be no undigested lactose for colonic bacteria to ferment and produce gas.

Answer:

B. Bacteria in his colon digest the lactose, producing gas.