The lactase enzyme helps your body digest lactose in dairy foods, but production often decreases with age. When levels are low, lactose intolerance symptoms can occur. Lactase supplements are a safe, effective way to support digestion and enjoy dairy without discomfort.
What is the lactase enzyme?
The lactase enzyme is a natural substance produced in the small intestine that helps your body digest lactose, the sugar found in milk and other dairy products. So if you are wondering what type of enzyme lactase is, the answer is: lactase is a digestive enzyme, which helps break down lactose into glucose and galactose. These smaller sugars can then be easily absorbed into the bloodstream and used for energy.
The enzyme belongs to a group called beta-galactosidases. In simple terms, that just means it specializes in splitting milk sugar into digestible parts. When this process works properly, dairy foods pass through the digestive system without causing discomfort.
The lactase enzyme structure is designed to do one job very efficiently: attach to lactose molecules and cut them into those two smaller sugars. While the structure itself is complex at a molecular level, what matters most is its function—without enough active lactase, lactose can't be properly digested.
For many people, lactase production naturally decreases over time. When that happens, dairy can start causing bloating, gas, cramps, or diarrhea. That's why understanding what lactase is and how the enzyme works is the first step to understanding lactose intolerance and how to manage it effectively.
Understanding the role of lactase in digestion
The function of the lactase enzyme is simple but essential: it allows your body to digest lactose, the natural sugar found in milk and dairy products such as cheese, yogurt, and cream. When you consume these foods, lactose travels to your small intestine. That's where the lactase enzyme steps in and breaks it down into glucose and galactose—two sugars your body can easily absorb and use for energy.
When this process works smoothly, dairy digestion happens quietly in the background. You don't feel anything unusual because lactose is fully processed before it reaches the large intestine. But when lactase levels are low, lactose remains undigested and moves into the colon, where gut bacteria start fermenting it. This fermentation produces gas and draws water into the bowel, which can lead to bloating, cramps, and diarrhea.
So while the lactase enzyme may be invisible, its role is incredibly important. It acts like a biological "key" that unlocks the nutrients in dairy foods. Without enough of this enzyme, even small amounts of lactose can trigger discomfort, turning everyday foods into a digestive challenge for many people.
What happens when lactase levels are too low?
When the body doesn't produce enough lactase, digesting dairy becomes more difficult. Instead of being broken down in the small intestine, lactose passes into the large intestine undigested. There, gut bacteria begin to ferment it, producing gas and drawing extra water into the bowel. This process can lead to uncomfortable digestive symptoms that often appear shortly after eating dairy.
At first, low enzyme activity may go unnoticed. Some people only feel mild bloating or fullness, while others experience stronger reactions. Over time, symptoms can become more noticeable as natural enzyme production continues to decline. This is why many people tolerate milk as children but struggle with it later in life.
Low lactase levels don't mean dairy is suddenly "bad" for you—it simply means your body can no longer process lactose efficiently on its own. Understanding what's happening inside your gut helps explain why symptoms appear and why they vary so much from person to person.
Causes and symptoms of low enzyme activity
Low enzyme activity can develop for several reasons. The most common cause is genetics—many people naturally produce less lactase enzyme after childhood. Illness, intestinal infections, inflammation, or conditions like celiac disease can also temporarily reduce enzyme levels by damaging the lining of the small intestine. In rare cases, babies are born with very low or no lactase production at all.
Symptoms usually appear within 30 minutes to two hours after eating dairy. They may include bloating, abdominal pain, gas, rumbling sounds in the stomach, diarrhea, and sometimes nausea. The severity depends on how much lactose is consumed and how much lactase enzyme the body still produces. Some people can handle small amounts of dairy, while others react strongly to even a sip of milk or a few spoons of yogurt.
The connection between lactase deficiency and lactose intolerance
Lactase deficiency is the underlying cause of lactose intolerance. In simple terms, when your body doesn't make enough of the enzyme, it can't properly digest lactose. The undigested sugar then triggers the digestive symptoms commonly labeled as lactose intolerance.
This connection explains why lactose intolerance is so different from an allergy or immune reaction. It's a digestive issue. The body isn't "attacking" dairy; it just lacks the tool needed to process it. That's also why symptoms are dose-dependent: the more lactose you eat, the more undigested sugars reach the colon, and the stronger the reaction becomes.
Understanding this link makes it easier to manage symptoms, whether through dietary choices, portion control, or lactase enzyme supplements.
Why lactase production decreases over time
For many people, the ability to digest dairy changes as they grow older. As infants and young children, humans typically produce high levels of lactase because milk is a primary food source. This early production supports rapid growth and development. However, once weaning occurs and milk becomes less central to the diet, the body often reduces enzyme production. This is a normal biological process and not a sign that something is "wrong".
Genetics play a major role in this decline. In large parts of the world, adults naturally produce less of the natural lactase enzyme. This pattern, known as lactase non-persistence, is the global norm. Only certain populations have genetic traits that allow them to continue producing high enzyme levels into adulthood.¹
Health factors can also affect production. Infections, inflammation, intestinal surgery, or chronic conditions like celiac disease can damage the lining of the small intestine, where lactase is made. When the lining is irritated or injured, enzyme output may drop temporarily or permanently.
Age-related digestive changes may further reduce enzyme activity over time. Even people who tolerated dairy for decades can suddenly notice bloating or discomfort after consuming foods like milk, cheese, or yogurt.
Because this decline is so common, many people look for ways to support digestion when symptoms appear. This is where lactase enzyme supplements come into play—a practical option we'll explore in the next section.
Living with low lactase levels
Living with low lactase levels doesn't have to mean giving up your favorite dairy foods. Today, many people rely on lactase enzyme supplements for lactose intolerance as a simple, effective way to enjoy milk, cheese, yogurt, and creamy desserts without discomfort. These supplements provide the enzyme your body no longer produces in sufficient amounts, helping to break down lactose before it causes digestive symptoms.
One of the biggest benefits of supplementing lactase enzyme is the flexibility it gives you. You don't need to follow a strict lactose-free diet or avoid social situations that involve food. Instead, you can take an enzyme tablet or capsule shortly before eating dairy and let it do the work for you. This makes eating out, traveling, and spontaneous meals much easier to manage.
Many people wonder whether supplementing lactase enzyme is safe. The short answer is yes. Lactase supplements are generally well tolerated because they simply replace a natural digestive enzyme. Side effects are rare, though a mild reaction to lactase enzyme supplements can occur in very sensitive individuals if too much is taken at once.
People also often wonder about the effectiveness of lactase enzyme supplements. Results vary depending on the dose, the amount of lactose consumed, and individual digestion. However, many users report significantly reduced bloating, cramps, and other symptoms when they take the enzyme correctly. In many cases, they are able to enjoy dairy again without any discomfort at all.
Knowing how much lactase enzyme to take is key. The right amount depends on your personal tolerance and the lactose content of your meal. Some people need only a small dose for yogurt or cheese, while others require a higher dose for milk-heavy dishes or desserts.
Overall, lactase supplements like the ones from LactoJoy offer a practical, science-based way to regain food freedom and enjoy dairy on your own terms.
