Lactose

Definition

Lactose is a disaccharide sugar composed of one molecule of glucose and one molecule of galactose, commonly found in milk and dairy products. It plays a significant role in nutrition, particularly as a source of energy, and is important in understanding carbohydrate metabolism and digestion.

5 Must Know Facts For Your Next Test

1. Lactose accounts for about 2-8% of the total weight of milk and is a major carbohydrate source for infants.
2. Individuals who lack sufficient lactase enzyme may experience lactose intolerance, leading to gastrointestinal symptoms after consuming dairy products.
3. Lactose can be used as a prebiotic, promoting the growth of beneficial gut bacteria.
4. The process of fermentation can convert lactose into lactic acid, which is utilized in yogurt production.
5. Some dairy products have lower lactose content due to fermentation processes, making them easier to digest for those with lactose intolerance.

Review Questions

• How does lactose function as a source of energy in the human body, and what role does lactase play in this process?
  • Lactose functions as an energy source by being broken down into its constituent monosaccharides, glucose and galactose, through the action of the enzyme lactase. Once digested, glucose can be readily used by cells for energy production through cellular respiration. Lactase is crucial for this process, as individuals who do not produce enough lactase cannot effectively digest lactose, leading to potential nutritional deficiencies.
• Discuss the implications of lactose intolerance on dietary choices and health in populations with varying levels of lactase persistence.
  • Lactose intolerance affects many individuals globally, particularly those from populations with low levels of lactase persistence. This condition influences dietary choices, often leading individuals to avoid dairy products or seek lactose-free alternatives. The impact on health can include reduced intake of calcium and vitamin D found in dairy, which are essential for bone health. Consequently, those with lactose intolerance must find alternative sources of these nutrients to maintain overall health.
• Evaluate the role of lactose in food production and its nutritional significance in different dietary contexts.
  • Lactose plays an important role in food production processes such as fermentation in yogurt and cheese making, where it contributes to flavor development and texture. In addition to its functional properties, lactose has nutritional significance; it serves as a source of energy while also acting as a prebiotic that supports gut health. The presence of lactose can vary across different dairy products, influencing their suitability for individuals based on their lactase levels, ultimately affecting dietary choices and nutrition across diverse populations.

Related terms

Glucose: A simple sugar that is an important energy source in living organisms and a component of many carbohydrates, including lactose.

Galactose: A monosaccharide that combines with glucose to form lactose; it is part of the sugar found in milk.

Lactase: An enzyme that breaks down lactose into glucose and galactose, allowing for its digestion and absorption in the intestines.