[Campbell Biology P.963] People with lactose intolerance lack sufficient lactase, leading to... | Practice Question

People with lactose intolerance lack sufficient lactase, leading to digestive issues after consuming dairy. If a lactose-intolerant person consumes yogurt containing lactase-producing bacteria, why would this likely provide only temporary relief of their symptoms, at best?

  • A: The bacteria in yogurt produce an insufficient amount of lactase to break down all the lactose consumed.
  • B: The bacteria producing lactase are transient and eventually pass through the digestive system, not establishing a permanent lactase source.
  • C: Yogurt contains other dairy components that also cause symptoms in lactose-intolerant individuals.
  • D: The lactase produced by yogurt bacteria is quickly denatured by stomach acid, rendering it ineffective.

Explanation

The "WHAT IF?" question in the text directly addresses this scenario. While yogurt contains bacteria that produce lactase, these bacteria are typically transient, meaning they do not permanently colonize the human gut. As they pass through the digestive system, their lactase production is short-lived, providing only temporary relief. For sustained relief, a continuous intake of such probiotics or the individual's own lactase production would be required.