Lactase tablets: how they work and when they may be appropriate
The essentials at a glance
Lactase tablets contain lactase, the enzyme that breaks lactose down into its two components in the small intestine. People who produce too little of it take it with their meal as a supplement. In 2024, IQWiG stated that its benefit has not yet been demonstrated by meaningful studies. At the same time, European food law permits a claim about lactose digestion if a serving contains at least 4,500 FCC units (FCC stands for Food Chemicals Codex, a unit of measurement for enzyme activity).
Both are presented side by side here because both are true. The text does not resolve the contradiction in favor of the tablets; instead, it explains exactly what each statement covers and what it leaves open.
You will first learn what lactase does in the body, followed by the evidence and the number on the package. From chapter five onward, the focus is on whether you need the tablets permanently or only for a while, and the final section covers alternatives that do not require a supplement at all.
What to expect in this article
1. Why milk causes problems for many people
2. What lactase does in the body
3. What lactase tablets do and what has been proven
4. FCC units: how to read the number on the package
5. Genetic, acquired, or temporary
6. Taking them correctly: timing, meals, and limits
7. Who tablets are suitable for and who should seek clarification first
8. Genetic or acquired: what a DNA test reveals
9. Alternatives without a supplement
10. What you can do now
Frequently asked questions
Sources
Why milk causes problems for many people
Lactose, technically known as lactose, is a disaccharide. It is too large to pass through the intestinal wall into the bloodstream as it is. Only when it is broken down into two simple sugars in the small intestine can the body make use of it.
If this breakdown does not take place, the lactose continues into the large intestine. There, bacteria take over what the enzyme did not manage to do. This produces gases and acids, which in turn cause the symptoms many people know: bloating, rumbling, pressure, and sometimes diarrhea. Our article on the symptoms of lactose intolerance explains in detail which symptoms are typical and how soon they occur after eating.
5 to 15 %
of people in Europe cannot digest lactose. Figure from IQWiG on gesundheitsinformation.de, as of 2024.
15 %
The Helmholtz Munich Allergy Information Service gives this figure for lactose intolerance among the population in 2023.
4 500
For a preparation to carry a claim about lactose digestion, Regulation (EU) No 432/2012 from 2012 requires 4,500 FCC units per serving.
The two percentages come from two sources with different scopes, which is why they are shown separately here rather than combined into a single figure. What they have in common is this: this is not a marginal issue.
Let us clear up one thing right away, because it is often confused. Lactose intolerance is not an allergy. In 2023, the Allergy Information Service of Helmholtz Munich classified it as a disorder of carbohydrate utilization and explicitly included it among non-allergic food intolerances. The immune system is not involved. The problem is a missing tool, not a lack of tolerance.
What lactase does in the body
Lactase is an enzyme in the lining of the small intestine. You can think of it as a locksmith at a very narrow passage: It breaks down each milk sugar molecule into two smaller parts, glucose and galactose, and only these two can pass through the intestinal wall.
In infants, this locksmith works at full capacity because milk is their only food. After that, production declines in many people. In 2024, the IQWiG described precisely this hereditary form as the most common: Lactose intolerance is usually hereditary.
Less enzyme does not automatically mean symptoms
There are several steps between the amount of enzyme and what you feel in your stomach. How much milk sugar a serving contains, whether you eat it on its own or as part of a larger meal, how quickly your intestines work, and which bacteria produce which gases there: all of this shifts the threshold. That is why one person can easily tolerate a latte but experiences symptoms after a glass of milk.
In practice, this means the question is rarely “milk or no milk.” It is how much milk sugar remains unnoticeable for you in which situation. We described how to observe yourself in this process without imagining symptoms in the article Recognize lactose intolerance and test yourself. This article focuses on the tablets.
At a glance: what lactase does in the body
In the small intestine, lactase breaks down milk sugar into glucose and galactose. If the enzyme is missing, the milk sugar reaches the large intestine, where bacteria ferment it and produce gases. A lactase tablet supplies the enzyme from outside along with the meal. It changes neither the intestinal lining nor enzyme production and works only for the meal with which you take it.
What lactase tablets do and what has been demonstrated
The principle is simple, and that is precisely what makes the tablets so popular: You swallow lactase produced outside the body together with the meal containing lactose. In the small intestine, the enzyme is supposed to take over the work that your own enzyme can no longer perform in sufficient quantities.
The evidence is less reassuring than the packaging might suggest. The Institute for Quality and Efficiency in Health Care writes on gesundheitsinformation.de:
Documented source
“However, it has not yet been demonstrated in meaningful studies that they can alleviate the typical symptoms.”
Institute for Quality and Efficiency in Health Care (IQWiG)
gesundheitsinformation.de, topic: lactose intolerance, 2024
Set against this is another equally official statement. Regulation (EU) No 432/2012 lists an authorized claim for the enzyme lactase in its annex: In essence, the authorized claim reads: Lactase improves lactose digestion in individuals who have difficulty digesting lactose. The regulation links this to a condition. The claim is reserved for food supplements that provide at least 4 500 FCC units per serving, together with the instruction to take the product with every lactose-containing meal. Source: Official Journal of the European Union L 136, 25 May 2012.
The contradiction is smaller than it appears, and it does not resolve itself in favor of the tablets. The authorized claim describes a digestive process: The enzyme supplied breaks down milk sugar. The IQWiG statement concerns something else, namely the symptoms you actually feel. The fact that a substance does what it is supposed to do in the laboratory and that people measurably feel better with it in everyday life are two different claims with two different burdens of proof.
What does this mean for you? Not that the tablets are worthless. Rather, no one can seriously guarantee you a specific effect, and your own experience is the only measure you have. Anyone who tries them should do so consciously, not as a long-term solution for symptoms that no one has ever assessed.
FCC units: how to read the number on the package
Almost every package has a number followed by three letters: FCC. This stands for Food Chemicals Codex, a set of standards that specifies how the activity of an enzyme is measured. FCC units are therefore not milligrams, but a measure of enzyme activity.
More units mean: more enzyme activity per tablet. They do not mean: more effective for you. This is where most package comparisons go wrong. The number describes the product, not your gut.
Key message
The FCC number indicates how much enzyme activity is contained in one portion. It says nothing about how much milk sugar you personally can tolerate.
There are two things worth checking on the packaging. First: Does the information refer to one tablet or to a portion consisting of several tablets? This is stated in small print below the nutrition table and affects every comparison between packages. Second: Does the manufacturer include the condition that the product must be taken with every lactose-containing meal? That is exactly what the 2012 European regulation requires if the claim about lactose digestion is used.
It is deliberately not stated here how many units are right for your portion of rice pudding. That is what the information on the packaging and the conversation at the pharmacy are for. A general recommendation would pretend that the amount of milk sugar in your food and your remaining activity are known. Neither is.
Genetic, acquired, or temporary
Whether you need tablets permanently depends less on the severity of your symptoms than on their cause. In 2024, IQWiG distinguishes the usually hereditary form from the acquired form, which is caused by other diseases. In technical terms, the hereditary variant is called primary, and the acquired variant secondary.
| Form | Cause | Course | Are tablets needed permanently? | How to recognize it | Source |
|---|---|---|---|---|---|
| Genetically determined (primary, meaning present from the outset) | Lactase production decreases after early childhood. In 2024, IQWiG states that lactose intolerance is usually hereditary. | It often begins during adolescence or early adulthood and persists. The predisposition does not change anymore. | Descriptively: usually yes, as long as lactose is consumed and the amount exceeds your individual threshold. | Hydrogen breath test at a medical practice, meaning measurement of the hydrogen content in the breath after drinking a lactose solution. A DNA test shows the predisposition, not the current condition. | IQWiG 2024 |
| Acquired (secondary, meaning resulting from something else) | Another disease damages the lining of the small intestine. In 2024, IQWiG cites Crohn's disease as an example. | It depends on the course of the underlying condition. If the mucous membrane improves, tolerance may improve as well. | Descriptively: often only as long as the underlying condition exists or the mucous membrane is irritated. | Through medical evaluation of the underlying condition, supplemented by the breath test. A DNA test does not capture this form. | IQWiG 2024 |
| Temporary after a gastrointestinal infection (special case of the acquired form) | The mucous membrane is temporarily irritated. The mechanism is the same as with the acquired form, but the cause is short-lived. | Limited in time, tied to the recovery of the mucous membrane. | Descriptively: generally no, but at most for this period. | During a medical consultation, because the timing of the symptoms is what matters here, not the predisposition. | IQWiG 2024, as a subgroup of the acquired form |
The standard method for classification is the hydrogen breath test at a medical practice. After drinking a lactose solution, the hydrogen content in the breath is measured several times, as IQWiG describes in 2024. We explain what other methods are available and how useful they are in comparison in the article Lactose intolerance self-test; Getting tested for lactose intolerance explains how testing works in practice.
Take it correctly: timing, meal, limits
The enzyme must be in the same place at the same time as the milk sugar. Therefore, taking it is tied to the meal, not the time of day. The 2012 European regulation requires precisely this wording for the approved claim: with every lactose-containing meal.
This entails limitations that are rarely stated on the package. A tablet works only for the meal with which you take it; it does not build up a reserve. It does not work retroactively once symptoms have begun. And it does not change the cause: Your own enzyme production remains as it is.
The tablet replaces an enzyme, not a diagnosis.
The second sentence is more important than the first. If symptoms persist despite taking tablets, that is not a reason to increase the dose on your own. It is an indication that lactose may not be the whole explanation. At precisely this point, the question belongs in the hands of a doctor, not in the next package.
Who lactase tablets are suitable for and who should be assessed first
Lactase tablets are an aid for known situations, not a tool for finding the cause. This distinction determines whether they make sense for you.
Lactase tablets are suitable if …
your intolerance has already been medically assessed and you know what triggers your digestive symptoms.
you eat dairy products only occasionally, for example when eating out, where you do not choose the ingredients yourself.
you understand the information on the package: units per serving, taken with a meal.
Have it assessed first if …
the symptoms are new, persist, or change without anyone having assessed them.
you lose weight unintentionally or blood appears in your stool. This should be assessed promptly at a medical practice.
it involves a child or symptoms persist despite taking tablets. Both are matters for a doctor's office.
Genetic or acquired: what a DNA test says about it
This is where an objection regularly arises, and one we consider justified: Do you need a genetic test to know whether to take tablets? No. To determine whether you can tolerate lactose today, the breath test at a medical practice is the way to go. A genetic analysis answers a different question, and only that one.
mybody®x (MYBODY Lab GmbH) offers a saliva analysis for this purpose. The “mybody® Metabolic Type” chapter includes the “Lactose Metabolism” report. The MCM6 gene, which controls the activity of the lactase gene LCT, is examined. The result shows the genetic predisposition and thus helps you distinguish the congenital form from an acquired one.
DNA analysis from saliva
NutriCare | INFINITY DNA test
At-home saliva sample. The “Lactose Metabolism” report in the “mybody® Metabolic Type” chapter shows the genetic predisposition through the MCM6 gene, which regulates the lactase gene LCT. It therefore distinguishes the congenital form from the acquired form. What it does not do: It does not measure current lactase activity, say anything about your symptoms, specify a dosage for a preparation, or replace the hydrogen breath test at a medical practice.
one of four tolerance reports
What such an analysis cannot do
The position paper of the German Nutrition Society stated in 2022 that evidence for the success of gene-based dietary recommendations is still generally lacking. This qualification is part of an honest picture. A predisposition is a data point, not an action plan.
Put simply: If you are only interested in whether you can tolerate a piece of cheesecake today, you do not need a genetic analysis. If you are interested in whether you are predisposed to it and likely to live with it, the analysis provides information about that which will not change.
Alternatives without a preparation
Tablets are not the only option, and for many people they are not even the most obvious one. Three options work without a preparation.
The first is portion size. Because symptoms depend on the amount, even a small sip of milk in coffee can shift the situation, especially when it comes with a larger meal rather than on its own on an empty stomach. The second option is lactose-free products: There, the lactose has already been broken down during production, so the enzyme has done its work before sale. The third option is selection. In long-aged cheeses, a large proportion of the lactose has been broken down through aging, and some people also tolerate fermented dairy products better than fresh milk.
What is deliberately missing here is a gram list. The amount of lactose a particular cheese contains varies with its degree of aging and production method, and our sources do not provide a figure for this. Instead of giving a number that looks precise but is not, this text refers you to the nutritional information on the package.
What you can do now
Back to the beginning: Lactose is too large to pass through the intestinal wall, and lactase makes it smaller. Everything this text discusses hinges on this one process. The tablet supplies the tool for one meal, no more and no less.
The order in which the steps make sense is: have your symptoms assessed before covering them up permanently with a preparation; the hydrogen breath test at a medical practice is the standard approach for this. Then, if you use tablets, read the amount per serving and take them with your meal. Finally, check how far you can get with portion size, lactose-free products, and aged cheese anyway.
And if you want to know whether you are predisposed to it: That is a separate question with a separate answer. It does not change what you eat tonight. It changes how you interpret it.
Frequently asked questions
Can I take lactase tablets preventively before I know whether I can tolerate lactose?
It is possible, but rarely sensible. Anyone who takes a preparation continuously without clarifying the cause may mask symptoms that have another cause and only realize it late. IQWiG also states in 2024 that a benefit for the typical symptoms has not yet been demonstrated by meaningful studies. The standard way to assess this in a medical practice is the hydrogen breath test: After drinking a lactose solution, the hydrogen level in the exhaled air is measured several times.
Are more FCC units always better?
No. FCC stands for Food Chemicals Codex and is a measure of enzyme activity. A higher number means more enzyme activity per serving, not a stronger effect for you. Regulation (EU) No 432/2012 merely sets a lower limit: only from 4,500 FCC units per serving may a food supplement carry the authorized claim regarding lactose digestion, together with the instruction to take it with every lactose-containing meal. The source is the Official Journal of the EU L 136 of May 25, 2012.
Is lactose intolerance the same as a milk allergy?
No, these are two different things. In 2023, the Helmholtz Munich Allergy Information Service classified lactose intolerance as a carbohydrate metabolism disorder and explicitly distinguished it from allergy-related reactions; it is classified there as a non-allergic food intolerance. In an intolerance, an enzyme is missing; the immune system is not involved. Lactase tablets therefore act exclusively on lactose and have nothing to do with an allergic reaction.
Do I have to take the tablets for the rest of my life?
That depends on the cause. In the usually hereditary form, the underlying situation remains unchanged as long as lactose is consumed, because the predisposition does not change. According to IQWiG 2024, the acquired form is caused by other diseases such as Crohn's disease; it is linked to their course and may change along with them. That is why it is worth distinguishing between the forms before settling on a long-term solution. Discuss the amount and frequency with the package information and your pharmacist.
What should I do if the symptoms persist despite taking tablets?
Then the amount is not the first thing to adjust, but whether lactose is really the whole explanation. Abdominal symptoms can have many possible causes, and the tablet addresses only one of them. In this case, speak with your doctor, especially if the symptoms are new, persist for a longer period, are accompanied by unintentional weight loss, or if there is blood in your stool. In children, the assessment should be carried out by a pediatrician from the outset.
Next step
Know whether it is innate
If you want to know your genetic predisposition for lactose metabolism, you will find it in the report from the NutriCare INFINITY DNA test. For the question of what you can tolerate today, the breath test remains the right approach in practice.
To the DNA test Compare test methodsRead more
You might also be interested in this
The role of predisposition in abdominal complaints and where its significance ends.
A sober assessment of what genetic nutritional analyses can and cannot show.
Sources
- Institute for Quality and Efficiency in Health Care (IQWiG): Lactose intolerance (as of 2024) - gesundheitsinformation.de
- European Commission: Regulation (EU) No. 432/2012, Annex; Official Journal of the European Union L 136 dated 25/05/2012 (paraphrased, without a link)
- Allergy Information Service, Helmholtz Munich: Food allergy, fundamentals (as of 2023) - allergieinformationsdienst.de
- Holzapfel C, Waldenberger M, Lorkowski S, Daniel H and DGE Working Group: Position paper of the German Nutrition Society on personalized nutrition, Molecular Nutrition and Food Research 2022, DOI 10.1002/mnfr.202200077
The frequency, distinction between hereditary and acquired forms, breath test, and assessment of the evidence from studies are based on [1]. The information on lactose digestion, including the lower limit of 4,500 FCC units, comes from [2] and has been paraphrased. The distinction from allergy and the second frequency figure come from [3], while the assessment of the significance of genetic nutritional analyses is based on [4]. Product information refers to the mybody®x product pages; the price and image were checked on 09/09/2026.
mybody®x Editorial & Expert Team
Intolerances Digestion Genetics and nutrition
This article was created by the mybody®x editorial and expert team. The people who contributed to it are listed on the authors page.
Published on 09/09/2026 · Last updated on 09/09/2026
The content is intended for general information and does not replace medical advice, diagnosis, or treatment. Reference ranges depend on the laboratory, method, and age - the information in your report is always authoritative.
The DNA analysis is intended for nutritional and lifestyle counseling. It is not a diagnostic procedure, does not predict diseases, and does not replace a medical examination or consultation. Genetic variants describe probabilities in population groups, not fixed outcomes for individuals. Our products are not intended to diagnose, treat, cure, or prevent diseases.
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