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Updated: May 18, 2026
04:41
Measuring Lactase Enzymatic Activity in the Teaching Lab
Published on: August 6, 2018
Summary
Individuals with lactose malabsorption experience milk intolerance, with symptoms worsening as milk
Area of Science:
- Gastroenterology
- Human Nutrition
Background:
- Lactose malabsorption is common.
- Milk lactose intolerance is a frequent concern for affected individuals.
Purpose of the Study:
- To investigate the relationship between lactose malabsorption and milk lactose intolerance.
- To quantify symptom occurrence based on milk lactose content.
Main Methods:
- A double-blind study involving 150 participants.
- Administration of 250 ml milk with varying lactose levels (0g, 12.5g, 37.5g) over 3 days.
- Lactose tolerance testing to classify subjects by lactase activity.
Main Results:
- No symptoms reported with lactose-free milk.
- Milk with 12.5g lactose caused symptoms in 37.1% of those with insufficient lactase activity.
- Milk with 37.5g lactose induced symptoms in 83.5% of those with insufficient lactase activity.
Conclusions:
- Subjects with lactose malabsorption are indeed milk-intolerant.
- Symptom frequency directly correlates with the lactose content in milk.
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