Lactose

Lactose is a type of sugar that is naturally found in milk and other dairy products. It is a disaccharide, meaning it is made up of two smaller sugar molecules: glucose and galactose. When lactose is consumed, the body breaks it down into these two components using an enzyme called lactase, which is produced in the small intestine.

Key Points about Lactose:

  • Chemical composition: Lactose (C₁₂H₂₂O₁₁) consists of one molecule of glucose and one molecule of galactose.
  • Lactase enzyme: To digest lactose, the body needs lactase. People who produce insufficient amounts of lactase often experience lactose intolerance, which can cause digestive issues like bloating, gas, and diarrhea after consuming dairy.
  • Sources: Lactose is found primarily in milk (from cows, goats, and other mammals) and dairy products like cheese, yogurt, and butter.
  • Lactose intolerance: This is a common condition, especially in adults, where the body cannot properly digest lactose. It is more prevalent in certain populations, such as those of East Asian, African, and Native American descent.

Lactose is an important energy source, particularly for infants, as milk is often a primary food source in early life. However, as people age, the production of lactase decreases in many individuals.