Lactose intolerance is a digestive condition that occurs due to the body’s inability to properly break down lactose, which is the natural sugar found in milk. This can lead to uncomfortable symptoms after consuming dairy products. While most people have trouble digesting lactose, not everyone develops visible symptoms. When symptoms do occur, the condition is known as lactose intolerance.
The body relies on an enzyme referred to as lactase, produced in the small intestine, to break down lactose so it can be absorbed. However, individuals with lactose intolerance have insufficient levels of lactase.
Despite low lactase levels, some people can still digest dairy products without any issues. For those who are lactose intolerant, reduced lactase levels often result in symptoms after consuming dairy.
Lactose malabsorption occurs when the small intestine cannot absorb lactose properly. Instead of being absorbed, the lactose travels through your digestive system unprocessed. When it reaches the large intestine, it can trigger symptoms, and this is what defines lactose intolerance.
However, lactose malabsorption doesn’t always result in lactose intolerance. You can have malabsorption without experiencing noticeable symptoms, meaning not all cases of malabsorption lead to intolerance.
Common symptoms of lactose intolerance are:
Usually, the symptoms result from undigested lactose reaching the large intestine. It typically takes 6–10 hours for food to travel to the large intestine after consumption and another 24–36 hours to pass through. As a result, symptoms may appear up to one or two days after eating foods containing lactose.
Lactose is found in most dairy products unless specifically removed. This comprises products made from cow or goat milk.
The amount of lactose varies between products. For instance, hard cheese contains less lactose than cream and fresh milk. However, a sprinkle of parmesan on the salad can be just fine.
If you are highly sensitive to lactose, even trace amounts can cause reaction symptoms. It’s also important to read food ingredient lists and nutrition labels, as lactose can be present in processed foods such as salad dressings, soup, and snacks. Sometimes, it is included in the prescription drugs you take.
Lactose intolerance is influenced by two key factors: lactose malabsorption and gut sensitivity. The most significant factor is lactose malabsorption, which occurs when the small intestine cannot effectively break down and absorb lactose. As a result, it enters the large intestine, which triggers symptoms.
The small intestine relies on lactase to break down lactose into small molecules, allowing it to be absorbed into the bloodstream. Many individuals produce lactase during infancy to assist in the digestion of breast milk, but the body naturally begins producing less lactase as they age.
Those with lactase deficiency are unable to properly digest lactose. While some may release more or less lactase, most people worldwide experience some level of lactose malabsorption. Only a small percentage of the population continues producing lactase even during adulthood.
Gut sensitivity refers to how an individual’s digestive system reacts to substances that are not fully digested, such as certain sugars or dietary fibers. These substances pass through the digestive system and feed the gut bacteria.
While most people can tolerate small amounts of undigested substances without severe symptoms, everyone’s body is unique. Intestinal health, genes, diet, and sensitives are factors that determine the levels of sensitivity to lactose.
Your symptoms will indicate how much lactose your body can tolerate, as your gut microbiome (various types of bacteria in the colon) plays a significant role in processing it.
The 4 primary types of lactose intolerance include:
The following factors are likely to make you or your child susceptible to lactose intolerance:
Lactose intolerance may be suspected depending on your symptoms and how they improve when you reduce dairy in your diet. To confirm the diagnosis, your doctor can perform one or more of these tests:
Treatment for lactose intolerance depends on the underlying cause. If the condition is triggered by another health issue, addressing that condition may help restore the body’s capacity to digest lactose, though this can take several months. In cases of other causes, discomfort caused by lactose intolerance can be avoided with a low-lactose diet.
To reduce lactose intake, you should consider:
Many foods contain lactose, so it’s important to always check labels. Foods such as snack foods, dried vegetables, candy, bakery items, dry mixes, and infant formulas may contain lactose. Additionally, many medicines, especially white tablets like birth control pills or drugs for stomach acid and gas, use lactose as a filler. Your GP or pharmacist can help you identify if any of your prescription medications contain lactose.
The high-lactose foods to be aware of include:
Lactose-free substitutes you can try include:
Lactose intolerance is usually not considered an illness; rather, it’s a natural dissimilarity in the manner in which our digestive systems function. In fact, the capacity to digest lactose beyond infancy is a somewhat new genetic adaptation, and not everyone has it. This is completely fine because it is possible to live healthily with lactose intolerance.
If you’re experiencing digestive symptoms and suspect they may be linked to dairy products, seek medical assistance. Your doctor can check for lactose intolerance and other potential reasons for your symptoms. If you are diagnosed with lactose intolerance, your provider will help you in modifying your lifestyle to manage the condition and avoid discomfort.
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