❓ why
Why do some people have lactose intolerance?
Human BiologyDigestion
Quick Answer
Lactose intolerance happens when the body makes too little lactase, the enzyme that digests milk sugar. Undigested lactose then reaches the colon and causes symptoms.
The Full Story
Lactase breaks lactose into glucose and galactose in the small intestine. In many mammals, lactase production drops after weaning, and many humans also reduce production with age. Without enough lactase, lactose is fermented by gut bacteria, leading to gas, bloating, cramps, and diarrhea. The trait is common worldwide and varies by ancestry, with lactase persistence being more common in populations with a long history of dairy farming.
Key Facts
1.Lactase digests lactose in the small intestine
2.Symptoms include gas, bloating, and diarrhea
3.Lactase persistence is more common in some dairy-farming populations
YouTube Angle
Suggested video title for this topic:
"Why milk bothers some people but not others!"