Lactose intolerance

Definition

Lactose intolerance is the inability to fully digest lactose, a sugar found in milk and dairy products, due to a deficiency of the enzyme lactase. This condition can lead to various gastrointestinal symptoms when individuals consume lactose-containing foods. Genetic predisposition plays a significant role in the prevalence of lactose intolerance among different populations, highlighting the importance of personalized nutrition therapy that considers an individual's genetic background and dietary needs.

5 Must Know Facts For Your Next Test

1. Lactose intolerance affects about 65% of the global population, with higher rates in certain ethnic groups such as East Asians, Native Americans, and some African populations.
2. Symptoms of lactose intolerance typically include bloating, gas, diarrhea, and abdominal pain after consuming lactose-containing foods.
3. The ability to digest lactose into adulthood is linked to specific genetic mutations that allow continued lactase production; this phenomenon is known as lactase persistence.
4. Management of lactose intolerance often involves dietary modifications, such as reducing or eliminating dairy products, or using lactase supplements to aid digestion.
5. Understanding one's genetic background can help tailor nutrition therapy for individuals with lactose intolerance, ensuring they receive adequate calcium and vitamin D from alternative sources.

Review Questions

• How does the genetic predisposition for lactase persistence influence dietary recommendations for individuals with lactose intolerance?
  • Genetic predisposition for lactase persistence significantly influences how individuals manage their lactose intake. Those with a genetic makeup that supports continued lactase production can usually tolerate dairy products without experiencing symptoms. In contrast, individuals with a genetic inclination toward lactose intolerance may need tailored dietary recommendations to minimize symptoms while ensuring they still meet their nutritional needs.
• What role does the enzyme lactase play in the digestion of lactose, and how does its deficiency lead to symptoms of lactose intolerance?
  • Lactase is crucial for breaking down lactose into simpler sugars, glucose and galactose, which can be absorbed by the body. When there is a deficiency of lactase, undigested lactose moves into the colon where it ferments, leading to gas production and water retention. This process triggers the gastrointestinal symptoms commonly associated with lactose intolerance, such as bloating, diarrhea, and abdominal pain.
• Evaluate the implications of lactose intolerance on nutritional therapy approaches for diverse populations based on their genetic backgrounds.
  • Lactose intolerance has significant implications for nutritional therapy as it necessitates a personalized approach based on genetic backgrounds. For populations with high rates of lactose intolerance, nutrition therapy must focus on alternative calcium and vitamin D sources while avoiding dairy. Meanwhile, individuals from populations with high lactase persistence can be encouraged to consume dairy as part of a balanced diet. This highlights the importance of understanding genetic variability when developing effective dietary interventions.

Related terms

Lactase: An enzyme produced in the small intestine that breaks down lactose into glucose and galactose for absorption.

Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols (FODMAPs): A group of short-chain carbohydrates that can cause digestive issues in some people, including those with lactose intolerance.

Genetic Variability: The differences in DNA among individuals that can influence traits such as lactase persistence or lactose intolerance.