Lactose
Many of us are familiar with symptoms like diarrhea, bloating, nausea, or vomiting after consuming cow's milk or other mammalian dairy products. These symptoms are often signs of Lactose Intolerance.
What is Lactose and Where is it Found?
Lactose is a type of sugar found naturally in the milk of all mammals. Therefore, it can be found in breast milk, cow's milk, goat's milk, and milk from other mammals. Beyond just milk, lactose is also an ingredient in various dairy products such as yogurt, cream, ice cream, and cheese, though usually in smaller quantities than in liquid milk.
Why Lactose Intolerance Occurs: The Role of the Enzyme Lactase
Normally, when we consume dairy products, lactose must be broken down in the digestive system by an enzyme called Lactase, which is produced in our small intestine. Lactase breaks down the large lactose molecule into smaller sugar molecules: glucose and galactose, which the body can then easily absorb and use for energy.
However, many people experience lactose intolerance because their bodies produce insufficient lactase to digest lactose. When lactose is not digested, the body cannot absorb it. This leads to the characteristic symptoms of lactose intolerance, including bloating, diarrhea, abdominal pain, nausea, and vomiting.
Causes of Insufficient Lactase Production
Several factors can lead to insufficient lactase production:
- Genetics: This is the most common cause.
- Gastrointestinal diseases: Such as Inflammatory Bowel Disease or Crohn's Disease.
- Small intestine surgery: Can affect enzyme production.
- Developmental factors: Typically, all newborns can digest lactose. However, after weaning, some individuals' bodies may stop
- producing lactase, which is why many people develop lactose intolerance as they grow older.
Additionally, congenital lactose intolerance can occur, primarily in premature infants whose small intestines are not yet fully developed, leading to insufficient lactase production. However, these symptoms may resolve as the infant's body matures.
Managing Lactose Intolerance
In the past, people with lactose intolerance were often advised to completely avoid milk and dairy products. However, current research suggests that individuals with lactose intolerance can consume dairy products in amounts their bodies can tolerate. This allows them to still receive essential calcium and other nutrients found in milk. Therefore, it's advisable to consult a doctor to determine your level of lactose intolerance and appropriate consumption limits.
- Approximate Lactose Content in Dairy Products:
- Cow's Milk (skim/low-fat/whole) (250 ml): 12 grams of lactose
- Goat's Milk 1 cup (250 ml): 9 grams
- Condensed Milk 1 cup (250 ml): 24 grams
- Ice Cream 1 cup (250 ml): 12 grams
- Cream 1 cup (250 ml): 8 grams
- Yogurt 1 cup (250 ml): 5 grams
- Cheese 1 ounce (28 grams): 1 gram
- Butter and Margarine: Very low lactose content
Beyond these specific products, many other foods use milk as an ingredient. The cooking processes often do not break down lactose, so these foods and beverages can still contain lactose. Examples include Tom Yum Nam Khon (creamy Thai soup), cream soups, carbonara sauce, puddings, and milky coffee.