When you hear Lactase, the first thing that probably comes to mind is milk or other dairy products. But there’s so much more to lactase than dairy. Today we’re going to break down this powerful and essential enzyme piece-by-piece to enable us to fully understand it as both a natural ingredient and a dietary supplement.
Table of Contents
What is Lactase?
Lactase is an enzyme needed for breaking down lactose in the body. Moreover, Lactose is a sugar commonly found in milk and milk products. If the body does not have enough lactase, the milk does not digest well. Unfortunately, this results in lactose intolerance. What’s more, the results of this intolerance includes a variety of problematic gastrointestinal reactions.
How Does Lactase Work?
Lactase starts in the lining of the small intestine. Its purpose is to break down lactose into glucose, which is essentially smaller sugar molecules. By breaking it down, it becomes more easily digestible. For that reason, lactase is fundamental in the digestion of milk and milk products.
What is Lactase Deficiency?
Lactase is an abundant enzyme during infancy due to our extreme consumption of milk. As we grow into adulthood, the production of lactase begins to naturally decline, which is a common human trait. However, being lactase deficient means not having enough lactase to properly break down the lactose from dairy products. Interestingly, this is how someone becomes lactose intolerant.
Amazingly, a study done in 2019 says that about 70% of the world’s population is lactase deficient or commonly referred to as lactose intolerant. While it is less common in the United States, some of the highest rates are seen in people of East Asian, West African, Jewish, Greek, Italian, and Arab descent.
Lactose Intolerance
Normally, the lactase enzyme is able to breakdown the lactose in dairy products into glucose, which is then processed and absorbed as it passes through the small intestine. However, when someone is lactase deficient, the lactose moves directly into the colon without absorbing or processing properly. While in the colon, the undigestible lactose interacts with normal bacteria, which then causes lactose intolerance. Symptoms of lactose intolerance include bloating, diarrhea, abdominal cramps, and gas. The symptoms begin to manifest about 30 minutes to a couple of hours after drinking or eating foods that contain dairy.
To break it down further for better understanding, there are three types of lactose intolerance. As you see below, those types are primary, secondary and congenital.
Primary Lactose Intolerance
Most people start life producing plenty of lactase. Not surprisingly, it is a necessity in infants since milk is the primary source of nutrition. As we grow into childhood, we begin to replace milk with other food sources. Although the production of lactase begins to decrease, it still remains at a high enough level in a typical adult diet. However, sometimes the production of lactase gets too low and makes milk products harder to digest. When this happens it results in primary lactose intolerance.
Secondary Lactose Intolerance
This type of lactose intolerance happens when the small intestine decreases the production of lactase. This reduction may be due to an illness, injury, or surgery that involves the small intestine. Additionally, illnesses linked to secondary lactose intolerance include Crohn’s disease, celiac disease, and bacterial overgrowth syndrome.
Crohn’s Disease
Crohn’s disease is a chronic inflammation of the gastrointestinal tract. About 3 million Americans suffer from the effects of Crohn’s every year. Moreover, it can start at any age, however, it is usually diagnosed between 20-30. Also genetic, most people who get Crohn’s disease have a parent, sibling, or child with the same condition. Additionally, Crohn’s affects any ethnicity, but it is more common in Caucasians. However, in recent years, rates are increasing among Asians and Hispanics.
Celiac Disease
Celiac disease is an autoimmune disease that damages the small intestine in people who are predisposed to having an intolerance to gluten. Gluten is a protein that is found in barley, rye, and wheat. The symptoms of celiac disease are very similar to lactose intolerance. Again, a person’s risk of developing celiac increases if another family member suffers from the same condition. What’s more, if a person has another autoimmune disease, it is more likely that they may develop another one like celiac.
Bacterial Overgrowth Syndrome
Another condition that results in lactose intolerance is bacterial overgrowth syndrome (BOS.) This characterizes clinical symptoms that happen when normally low levels of bacteria living in the duodenum, stomach, proximal ileum, and jejunum increase considerably or are overtaken by other pathogens. Moreover, excess bacteria may consume important nutrients, including vitamin B12 and carbohydrates. This consumption leads to calorie deprivation and a deficiency in the levels of B12. Therefore, the symptoms of BOS are much the same as those of lactose intolerance.
Developmental or Congenital Lactose Intolerance
Although babies born with lactose intolerance is rare, the condition is a result of an absence of lactase activity during fetal development. Its cause is by inheritance of a recessive gene that must be present in both the mother and father.
Premature babies may also have lactose intolerance due to lower levels of lactase activity. This is because the small intestine does not fully develop lactase cells until late in the third trimester.
Diagnosing Lactose Intolerance
Your doctor may suspect lactose intolerance based on a variety of symptoms. However, in order to confirm the diagnosis, your doctor may want to do some tests. Below are the most common tests to confirm or deny a lactose intolerance diagnosis.
Hydrogen Breath Test
In this test, the patient drinks a beverage that is high in lactose. At this point, if the body does not digest it correctly, it ferments in the colon. To measure it, patients do a breath test. In a normal reading, hydrogen is barely detectable. This fermentation causes excess hydrogen and other gases that the body eventually exhales. During a breath test, higher than normal amounts of hydrogen will indicate that lactose is not being properly absorbed.
Lactose Tolerance Test
For this, a couple of hours after consuming the liquid high in lactose, a blood test is taken to measure the amount of glucose in the bloodstream. If the level of glucose does not rise, it signals that the body isn’t digesting and absorbing the lactose drink properly.
Stool Acidity Test
A stool acidity test may be used in infants and children who cannot perform the two previous tests. This is done by measuring the lactic acid from a stool sample.
Lactase Supplements
Taking a lactase supplement may help ease or even prevent the symptoms from lactose intolerance. In a study performed in 2010 and published in the European Review for Medical and Pharmacological Sciences, it is noted that lactase supplements worked better to help lessen the effects of lactose intolerance as compared to probiotics such as L. reuteri.
The study involves 60 adults over a 10-day period. The participants were given one lactase supplement 15 minutes before a meal that included some dairy. The results show that the supplement normalized the metabolization of lactose better than the probiotic, and it also worked better to alleviate lactose intolerance symptoms.
Lactase supplements may also help users to meet daily calcium needs by allowing an increase of dairy in your diet. Allowing dairy to be part of your diet helps build and maintain healthy bones. Moreover, a 2019 study shows that being lactose intolerant increases the risk of decreasing bone density and fragility fractures during old age.
Lactase Doses
Lactase supplements come in capsule, tablet, or powder form. The average doses range from 6,000 – 9,000 IU (international units) and are taken right before a meal that contains dairy products. Other users use 2,000 IU’s of lactase powder per two cups of milk to alleviate symptoms.
It’s best to start off on the lower range dosage until symptoms are within a healthy range. Taking smaller amounts have less effect on blood sugar and saves you money without compromising its effects.
It is not advisable to consume lactase supplements past their expiration date. Additionally, you must store them at room temperature in a container with a good seal.
If symptoms still occur after taking a lactase supplement, it’s possible that the supplement was not taken properly. Remember that it’s best to take the dosage prior to eating dairy. Interestingly, it is possible to extend the benefits by taking another dose after 20 – 30 minutes. This is beneficial if you eat dairy products over a longer time.
Lactase Supplement Side Effects
With no real side effects, lactase supplements are considered safe and well-tolerated for most people. However, people who have diabetes must use caution when using lactase supplements. Because the purpose of lactase is to break down lactose into simple sugars for better absorption, lactase supplements may increase blood glucose levels to unsafe levels for diabetics. Though it usually does not cause significant issues, it is important to check blood sugar levels 20 – 30 minutes after taking a lactase supplement to ensure sugar levels are within a normal range.
It is not advisable that women who are pregnant or breastfeeding to take lactase supplements since there isn’t enough research and information to safeguard their health. Also, it is not known if lactase supplementation results in interactions with other prescription medications or supplements.
Where to Buy Lactase
Lactase supplements are bought in many drugstores, dietary supplement stores, or natural foods stores. It’s also purchased online and is found in many digestive enzyme mixes like this one. Additionally, there is no need for a prescription to place an order.
Please note that Lactase supplements are not under regulation by the United States FDA. So, in order to ensure the safety and quality of your purchase, be sure to look for brands with independent certifications by a third party.

Other Sources of Calcium
If you find that taking a lactase supplement alone is not working for you, there are a variety of other sources of calcium to consider in order to meet the RDA (recommended dietary allowance) of calcium. Below is a list of food items that are also a good source of calcium.
- Bok choy
- Broccoli
- Calcium-fortified orange juice
- Calcium-fortified soymilk
- Tofu made from calcium sulfate
- Kale
- Whole wheat bread
Keep in mind that for women 18-50 and men 18-70, the RDA of calcium is 1,000mg a day. If you are a woman over 50, a daily calcium supplement may also help meet the RDA.
Conclusion
Lactase is an enzyme that is found in the small intestine that is needed in order to break down the lactose found in milk and milk products. If the body does not produce enough lactase, then it won’t be able to digest milk very well, resulting in lactose intolerance. When someone is found to be lactose intolerant, they may suffer from an array of uncomfortable symptoms like bloating, gas, diarrhea and, stomach cramps. Therefore, many people take lactase supplements to reduce or even prevent lactose intolerance symptoms.
These statements have not been evaluated by the Food and Drug Administration. Products discussed are not intended to diagnose, treat, cure, or prevent any disease.