Laktóztolerancia

Laktóztolerancia refers to the ability of an individual to digest lactose, a sugar found in milk and dairy products. Most mammals, including humans, produce the enzyme lactase in their small intestine, which breaks down lactose into glucose and galactose, allowing for absorption. This is essential for infants to digest breast milk.

However, in many populations, lactase production significantly decreases after weaning, a phenomenon known as lactase non-persistence. This is the ancestral human condition. Individuals with lactase non-persistence may experience digestive symptoms such as bloating, gas, diarrhea, and abdominal pain after consuming foods containing lactose. This condition is commonly referred to as lactose intolerance.

Lactose intolerance is not an allergy to milk; it is a digestive issue. The severity of symptoms can vary depending on the amount of lactose consumed and the individual's remaining lactase activity. In some cases, people with lactase non-persistence can still tolerate small amounts of lactose, especially when consumed with other foods.

Genetically determined lactase persistence, the ability to continue producing lactase into adulthood, is a relatively recent evolutionary adaptation that arose independently in several human populations, particularly in Northern Europe and parts of Africa and the Middle East. This adaptation allowed these populations to utilize milk from domesticated animals as a significant source of nutrition.

Diagnosis of lactose intolerance is typically based on symptoms and can be confirmed through a lactose breath test or a hydrogen breath test, which measures the amount of hydrogen expelled after consuming lactose. Management usually involves reducing or avoiding lactose-containing foods and beverages or using lactase enzyme supplements.