Unlike in childhood, when milk was easily digested, many people become lactose intolerant as adults. This is caused by a lack of the enzyme that breaks down lactose, and lactose-free milk solves this problem. Explain the causes of lactose intolerance and how to treat it.
Have you ever seen a product called “easy-to-digest milk” and wondered why it has this name? Thinking backwards, is milk an indigestible product? Many people say they have experienced discomfort after drinking milk. Most of them probably didn’t have any problems when they were younger, but as they grew up, they started to experience this discomfort more and more. It’s a phenomenon that affects 8 out of 10 adults, which is both curious and strange, but most people don’t go to the doctor about it or try to fix it, because they think that milk consumption is only essential for growing children, and that adults who have finished growing up can just stop drinking milk and not feel sick. Even if you don“t have a degree in food and nutrition, you know that calcium is important for bone growth, but it”s often overlooked that bone health is very important at any age. Bone health, especially in later life when fractures and osteoporosis are more common, is highly dependent on calcium intake in adulthood, so it’s essential to drink milk as an adult. However, many people avoid milk as adults because of the diarrhea, abdominal pain, and gas they experience after consuming it. This inability to digest milk is known as lactose intolerance. As adults need a significant calcium intake, lactose-free milks are being developed that can be consumed by people who suffer from this condition.
You can probably guess from the name “lactose-free milk for lactose intolerant people” that lactose is the substance causing the problem. So what is lactose? It is literally the sugar in milk, also called lactose because it is found only in mammalian milk. In other words, lactose is a carbohydrate found in milk or breast milk. Glucose is a type of monosaccharide, the most basic type of carbohydrate, and lactose is a disaccharide, which is a combination of two of these monosaccharides. In other words, if glucose is a single person, lactose is a couple holding hands. When you drink milk, lactose travels through your esophagus and stomach to your intestines, where it absorbs nutrients into your body. It”s important to note that the intestine has a pathway that only allows nutrients that the body needs to move through. Only then does it enter the bloodstream and travel throughout the body; if it doesn’t, it stays in the intestines and is later eliminated. The body has a pathway for transporting monosaccharides, which allows glucose to enter the body, but for disaccharides, there is no such pathway, so the body won’t let lactose through. Just as you have to go through the turnstiles one by one to travel on the subway of blood, a couple that has always been together has to let go and go through one by one. But lactose doesn’t unbind easily, so what’s needed is a “couple breaker,” or digestive enzyme. It breaks the bonds of the disaccharide and splits it into two monosaccharides. Each monosaccharide can then be absorbed into the body. Lactose intolerance is caused by a lack of this enzyme, which is unable to break down lactose into monosaccharides. When lactose isn”t absorbed, it remains in the intestines and causes uncomfortable symptoms.
So, why is lactase deficient? If you had no problems during your childhood when you were nourished by formula or breast milk, you probably had enough lactase in your system. However, as we grow up, we start eating rice instead of milk, and as our intake of lactose decreases, our bodies no longer feel the need to make lactase enzymes. The body has decided that it is inefficient to keep enzymes ready for lactose that might come in at any time. It’s not that the body is incompetent for not secreting the enzyme, but rather that it’s making a smart choice to use its energy more efficiently elsewhere.
When you don’t absorb lactose due to a lactase deficiency, you don’t just miss out on nutrients, you get diarrhea and abdominal pain. The reason diarrhea occurs is due to osmosis. To understand osmosis, we must first understand diffusion. Imagine a room full of people. People will bump into each other and feel uncomfortable. If you open the door to the next room, people will move into the larger space and there will be a balanced distribution of people in both rooms. This movement of a substance from a higher concentration to a lower concentration is called diffusion. On the other hand, osmosis occurs when the substance cannot pass through. If the door is too small for people to pass through, we try to solve the problem by increasing the size of the crowded room. Osmosis is the movement of water from a lower concentration to a higher concentration when a substance cannot move from a higher concentration to a lower concentration. In people who are lactose intolerant, lactose accumulates after drinking milk because it cannot be absorbed in the small intestine. In this case, lactose cannot diffuse, and water from the body enters the small intestine by osmosis. This results in loose stools and diarrhea.
The main cause of abdominal pain and gas is bacterial fermentation. The human intestine is inhabited by bacteria such as E. coli, which are responsible for breaking down substances in the intestine. When lactose reaches the colon of a lactose intolerant person, it is fermented by bacteria, which converts it into lactic acid, CO₂, and hydrogen. The gases produced in the colon are expelled as gas, and the lactic acid accelerates osmosis. It also promotes peristalsis, which causes the colon to move excessively and causes abdominal pain.
To eliminate this discomfort, lactose-free milk is made in two ways. The first is to physically remove the lactose. The lactose is removed during the manufacturing process, eliminating the root of the problem. The second is by adding lactase enzymes to the milk. This method breaks down the lactose into monosaccharides beforehand, which helps to prevent the problem from occurring in the body.
According to the latest National Health and Nutrition Examination Survey, adults consume less than 80% of the recommended calcium intake. Despite the fact that calcium is an essential nutrient for adults, not many people pay attention to their dairy intake. This is because lactose intolerance often leads to a natural avoidance of milk as an adult. However, the fact that we have to eat foods that we can“t digest in order to make them digestible is a paradoxical indication that they”re no longer a choice, but a necessity.
