Lactase

Lactase is an enzyme that is naturally produced by the human body. Enzymes are substances that trigger biochemical reactions in organisms. The function of lactase enzymes is to break down lactose, a type of sugar that is found in milk and other dairy products. This enables the body to absorb the energy provided by lactose sugars.

People whose bodies do not naturally produce enough lactase are at higher risk of suffering from a condition known as lactose intolerance. Lactose-intolerant individuals typically experience symptoms including bloating, stomach pain, nausea, gassiness, diarrhea, and vomiting after consuming milk or other foods containing milk or dairy-based ingredients.

Overview

Lactase encoding is governed by a gene found on chromosome 2, which is the second-largest chromosome in the human body. Chromosome 2 contains approximately 1200 to 1,400 genes that tell the body how to build proteins.

Human beings, along with most other mammals, naturally display elevated lactase levels in their intestinal tracts at birth. This is because most mammals are nourished from birth with their mother’s milk, which contains dense concentrations of lactose. In humans, the natural presence of lactase enzymes typically begins to decline as children are weaned off milk and begin to eat other foods. Doctors and scientists refer to this phenomenon as lactase non-persistence. In lactase non-persistent individuals, lactase levels can fall by as much as 90 percent by the time a child reaches four years of age. Rates of lactase decline are higher among children who eliminate milk and dairy altogether after transitioning from breast milk or infant formula to other foods.

However, lactase non-persistence is not a universal phenomenon. Individuals who continue to display high levels of lactase activity after weaning are termed lactase persistent. Studies have associated lactase persistence with certain types of chromosomal mutations, especially mutations affecting chromosome 2. People who are lactase persistent can continue to consume large quantities of milk or dairy products throughout life without experiencing any symptoms of intestinal discomfort. Research suggests that lactase persistence represents an evolutionary adaptation that enables humans to consume the milk and milk products of other animals. Lactase persistence is especially common among individuals of northern European and East African descent.

Conversely, lactase non-persistent individuals can only consume limited amounts of milk or dairy products without developing mild to moderate gastrointestinal discomfort. Lactose intolerance is indicated if an individual displays intense symptoms after consuming only very small quantities of milk or foods containing dairy-based ingredients.

Individuals with lactose sensitivities are frequently advised to take dietary supplements containing lactase that are known to ease the stomach discomfort associated with the consumption of milk and dairy products. Milk and dairy-based foods contain high levels of calcium and other minerals and nutrients that are essential for good health. Doctors and nutritionists tend to encourage lactose-sensitive and lactose-intolerant individuals to use lactase supplements to treat their condition rather than avoid dairy altogether.

Lactase supplements have excellent safety profiles. When used in recommended dosages, they are generally considered safe and have no known side effects and display no known drug interactions.

Bibliography

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