Can i develop a lactose intolerance
Lactose intolerance - NHS
Lactose intolerance is a common digestive problem where the body is unable to digest lactose, a type of sugar mainly found in milk and dairy products.
Symptoms of lactose intolerance
Symptoms of lactose intolerance usually develop within a few hours of consuming food or drink that contains lactose.
They may include:
- farting
- diarrhoea
- a bloated stomach
- stomach cramps and pains
- stomach rumbling
- feeling sick
The severity of your symptoms and when they appear depends on the amount of lactose you have consumed.
Some people may still be able to drink a small glass of milk without triggering any symptoms, while others may not even be able to have milk in their tea or coffee.
When to seek medical advice
The symptoms of lactose intolerance can be similar to several other conditions, so it's important to see your GP for a diagnosis before removing milk and dairy products from your diet.
For example, the symptoms above can also be caused by:
- irritable bowel syndrome (IBS) – a long-term disorder that affects the digestive system
- milk protein intolerance – an adverse reaction to the protein in milk from cows (not the same as a milk allergy)
If your GP thinks you have lactose intolerance, they may suggest avoiding foods and drinks containing lactose for 2 weeks to see if your symptoms improve.
What causes lactose intolerance?
The body digests lactose using a substance called lactase.
This breaks down lactose into 2 sugars called glucose and galactose, which can be easily absorbed into the bloodstream.
People with lactose intolerance do not produce enough lactase, so lactose stays in the digestive system, where it's fermented by bacteria.
This leads to the production of various gases, which cause the symptoms associated with lactose intolerance.
Depending on the underlying reason why the body's not producing enough lactase, lactose intolerance may be temporary or permanent.
Most cases that develop in adults are inherited and tend to be lifelong, but cases in young children are often caused by an infection in the digestive system and may only last for a few weeks.
Who's affected
In the UK, lactose intolerance is more common in people of Asian or African-Caribbean descent.
Lactose intolerance can develop at any age.
Many cases first develop in people aged 20 to 40, although babies and young children can also be affected.
Is it an allergy?
Lactose intolerance is not the same as a milk or dairy allergy. Food allergies are caused by your immune system reacting to a certain type of food. This causes symptoms such as a rash, wheezing and itching.
If you're allergic to something, even a tiny particle can be enough to trigger a reaction, while most people with lactose intolerance can still consume small amounts of lactose without experiencing any problems, although this varies from person to person.
Treating lactose intolerance
There's no cure for lactose intolerance, but cutting down on food and drink containing lactose usually helps to control the symptoms.
Lactose-free products include:
- lactose-free cows' milk
- soya milks, yoghurts and some cheeses
- rice, oat, almond, hazelnut, coconut, quinoa and potato milks
Your GP may also recommend calcium and vitamin D supplements.
You may be advised to take lactase substitutes, which are drops or tablets you can take with your meals or drinks to improve your digestion of lactose.
Complications of lactose intolerance
Milk and other dairy products contain calcium, protein and vitamins, such as A, B12 and D.
Lactose also helps your body absorb a number of other minerals, such as magnesium and zinc.
These vitamins and minerals are important for the development of strong, healthy bones.
If you're lactose intolerant, getting the right amount of important vitamins and minerals can prove difficult.
This may lead to unhealthy weight loss and put you at increased risk of developing the following conditions:
- osteopenia – where you have a very low bone-mineral density; left untreated, it can develop into osteoporosis
- osteoporosis – where your bones become thin and weak, and your risk of breaking a bone is increased
- malnutrition – when the food you eat does not give you the nutrients essential for a healthy functioning body; this means wounds can take longer to heal and you may start to feel tired or depressed
If you're concerned that dietary restrictions are putting you at risk of complications, you may find it helpful to consult a dietitian.
They can advise you on your diet and whether you require food supplements.
Your GP should be able to refer you to an NHS dietitian free of charge. Or you can contact a private dietitian.
The British Dietetic Association has information on how to find a private dietitian.
Page last reviewed: 25 February 2019
Next review due: 25 February 2022
Mayo Clinic Q and A: Lactose Intolerance Can Develop at Any Age
-
By
Liza Torborg
DEAR MAYO CLINIC: What would cause someone to become lactose-intolerant later in life? I’m in my 40s and have never had an issue with dairy, but, now, I can’t seem to have it without problems. Do I need to see a doctor to be tested for allergies, or should I just avoid dairy?
ANSWER: Lactose intolerance isn’t a true allergy, and it can develop at any age.
In some people, lactose intolerance may be triggered by another medical condition, such as Crohn’s disease. In others, it develops without a specific underlying cause. It would be a good idea to have your condition evaluated by your doctor to confirm that what you’re dealing with truly is lactose intolerance.
Lactose intolerance results from a problem with the carbohydrate lactose, a type of sugar found in dairy products. When you eat or drink dairy products, enzymes in your small intestine digest lactose, so the body can make energy. In people with lactose intolerance, a certain enzyme, called lactase, is missing from the body. When those people eat dairy products, the body has no way to break down the lactose. This leads to fermentation of the sugar in the intestines and triggers symptoms, such as diarrhea, nausea, abdominal cramps, bloating and gas.
Sometimes, lactose intolerance develops when the small intestine’s production of lactase decreases after an illness, injury or surgery involving the small intestine.
This is called secondary lactose intolerance. Among the diseases associated with this kind of lactose intolerance are celiac disease, bacterial overgrowth and Crohn’s disease. Treatment of the underlying disorder may restore lactase levels and improve symptoms.
More common than secondary lactose intolerance is primary lactose intolerance. People who develop primary lactose intolerance start life making normal levels of lactase — a necessity for infants, who get all their nutrition from milk. As children replace milk with other foods, lactase production normally decreases. It stays high enough, though, to digest the amount of dairy in a typical adult diet. In primary lactose intolerance, lactase production declines below normal at some point for reasons that are unclear. The low amount of lactase then makes milk products difficult to digest and leads to lactose intolerance symptoms.
Your doctor can confirm a diagnosis of lactose intolerance with a clinical test. One that’s often used is a lactose tolerance test.
It assesses your body’s reaction to a dose of lactose. After you consume a drink containing lactose, a sample of your blood is taken to measure glucose levels. If your glucose level does not rise, it means your body isn’t properly digesting and absorbing the lactose.
Alternatively, another test called the hydrogen breath test may be used. This test also requires you to consume a drink that contains high levels of lactose. Your doctor next measures the amount of hydrogen in your breath. Normally, very little hydrogen is detectable. However, if your body doesn’t digest the lactose, the fermentation reaction in your colon releases hydrogen and other gases. Your intestines absorb those gases, and you exhale them. Larger-than-normal amounts of hydrogen measured during this test are a sign that your body isn’t fully digesting and absorbing lactose.
If you have lactose intolerance, there isn’t a way to cure it. The most effective way for people with lactose intolerance to get relief from symptoms is to lower the amount of dairy products they eat.
You may be able to use dairy products that have reduced levels of lactose or are lactose-free. Some people who have lactose intolerance benefit from taking lactase enzyme supplements, as well.
If test results do not point to lactose intolerance, your doctor may recommend additional tests to check for another condition that could be causing your symptoms, such as a milk allergy, intestinal disorders or other problems within your digestive tract. — Dr. Rohit Divekar, Allergic Diseases, Mayo Clinic, Rochester, Minnesota
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what is true and what is not?
This is the second article in a series on lactose intolerance. In it, we analyze the most popular myths about this condition.
From the previous article it was possible to find out what causes lactose intolerance and what types it can be divided into. In this material, we understand how this condition differs from allergies, at what age it appears more often, and also what intolerance can be confused with and how to diagnose it.
If you have experienced intestinal discomfort after dairy products or have heard that milk is harmful for adults, this series of articles is for you. In three materials, we will talk about what lactose intolerance is, what types it is divided into, we will analyze the most common misconceptions, and also clarify how to live with it. nine0008
Contents
- Lactose intolerance and food allergy are not the same thing
- Similar symptoms may occur due to other diseases
- Intolerance does not always occur from birth
- Lactose intolerance can be diagnosed
Lactose intolerance and food allergy are not the same thing
Lactose intolerance occurs when a person's small intestine does not produce enough lactase enzyme.
This enzyme converts milk sugar (lactose) into simple sugars, which are then released into the bloodstream through the lining of the small intestine. nine0025
If there is little or no lactase, lactose enters the large intestine with food. There, bacteria begin to process it, and not sugars appear from lactose, but fatty acids, carbon dioxide, hydrogen and methane. This causes people to experience bloating, stomach pain, and other symptoms of lactose intolerance.
In allergies, the body's immune system reacts to milk protein rather than milk sugar. The symptoms of this condition also differ - more often itching, rash or swelling occurs. nine0005
If milk is an allergen for a person, then even a sip may be enough to immediately start symptoms.
And most people with lactose intolerance can eat small amounts of lactose and have no problems (although this varies from person to person).
If a person has frequent diarrhea or bloating, it is not necessarily lactose intolerance.
Similar symptoms can also occur due to other illnesses, such as irritable bowel syndrome or celiac disease. And sometimes even lactose intolerance can be secondary - due to some drugs or diseases that affect the intestines, such as ulcerative colitis. nine0025
Therefore, it is important to consult a physician to clarify the diagnosis before making it yourself and eliminating milk and dairy products from your diet.
In addition, limiting any food groups can cause vitamin and mineral deficiencies. So, when you refuse milk, sometimes there is a lack of calcium and vitamin D. This is another reason not to self-medicate.
Lactose intolerance does not always appear immediately from birth
Lactose intolerance usually first occurs between 20 and 40 years of age. This is due to the fact that most people in the world are faced with primary lactose intolerance. And this condition progresses in adulthood, when children with it are able to digest lactose.
nine0005
But congenital lactase deficiency in infants is a rare disease that can only be transmitted if both parents have a specific mutation in a certain gene.
Lactose intolerance can be diagnosed with tests
Doctors have ways to confirm this diagnosis. Most often, specialists use diary keeping, a hydrogen breath test, and a blood test for lactose tolerance.
The diary helps track the correlation of symptoms and foods a person eats over several weeks. The hydrogen breath test measures the amount of hydrogen before and after ingestion of a lactose-laden liquid. If there is more hydrogen, this indicates a lack of lactase in the body (because it means that lactose is processed not in the small intestine, but in the large intestine by bacteria). nine0025
During the blood test, you will also need to drink a liquid with lactose. If after that a low level of sugar is found in the blood, this means that lactose has not decomposed into simple sugars in the small intestine and the person is probably lactose intolerant.
In rare cases, doctors may use a biopsy of the small intestine to distinguish between primary and secondary lactose intolerance.
There is also a genetic test for primary lactose intolerance. nine0033It does not take long to run, but can only be used in European and North African populations.
In the final article, we will look at how to live with lactose intolerance, what foods can and cannot be consumed by people with this condition.
The results of the Atlas Genetic Test can provide not only data on the risk of developing certain diseases and the status of carriers of hereditary diseases, but also the characteristics of metabolism and a predisposition to intolerance to certain nutrients. Including find out if you have breakdowns in the genes associated with lactose. nine0008
- Mayo Foundation for Medical Education and Research, Lactose intolerance, 2021
- National Health Service, Lactose intolerance, 2021
- MedlinePlus, Lactose intolerance, 2021
- UpToDate, Lactose intolerance: Clinical manifestations, diagnosis, and management, 2021
- UpToDate, Patient education: Lactose intolerance (The Basics), 2021
What is lactose intolerance?
This is the first article in a series on lactose intolerance.
In it, we will tell you what it is, what this problem is associated with and what types it can be divided into. nine0003
If you have experienced intestinal discomfort after dairy products or have heard that milk is harmful for adults, this series of articles is for you. In three materials, we will talk about what lactose intolerance is, what types it is divided into, we will analyze the most common misconceptions, and also clarify how to live with it.
Contents
- 1. What is lactose intolerance
- 2. How genes affect it
- 3. Other causes
nine0013 4. NoteWhat is lactose intolerance
This is a condition that makes it difficult for the body to digest milk and dairy products. Lactose (milk sugar) intolerance can cause diarrhea, pain, abdominal cramps and bloating, flatulence, and vomiting. Symptoms appear within a few hours after ingestion of lactose-laden foods or drinks such as milk, yogurt, or cheese.
Humans normally produce lactase in the small intestine, an enzyme that breaks down lactose into other sugars (glucose and galactose).
If there is not enough lactase, lactose moves to the large intestine, where bacteria begin to process it. But here, it is not sugars that appear from lactose, but fatty acids, carbon dioxide, hydrogen and methane. This is what causes all the symptoms. nine0005
Genes are a common cause of lactose intolerance
There are many types of lactose intolerance. The most common in the world is primary lactose intolerance. In this case, the body produces a sufficient amount of lactase during childhood, but loses this ability with age due to a gradual decrease in the activity (expression) of the LCT gene.
Primary lactose intolerance is more common among African and Asian populations, but among Europeans in adulthood this problem occurs less frequently. This is attributed to a special mutation that appeared in the ancestors who first domesticated cows (and other animals that give milk) and constantly consumed dairy products. nine0005
There is also a congenital lactose intolerance.
The body of such people does not produce lactase from birth. This is a rare disease that is transmitted in an autosomal recessive manner of inheritance.
This means that both parents must have a genetic mutation in a particular gene in order for them to pass it on to their child. The largest number of cases of congenital lactose intolerance was registered among the population of Finland (1 case per 60,000 children).
What else causes lactose intolerance
Another type is secondary lactose intolerance, or lack of lactase, which occurs due to problems in the intestines. It can happen at any age after an injury, surgery, or medication such as chemotherapy or long courses of antibiotics.
It can also happen in diseases like gastroenteritis, Crohn's disease, ulcerative colitis and celiac disease. Treating the underlying condition over time can restore lactase levels and improve symptoms of lactose intolerance. nine0005
Another isolated lactose intolerance associated with preterm birth.
Some babies born before the 37th week of pregnancy have temporary lactose intolerance. This is because their small intestine has not fully developed by the time of birth, but as the baby grows older, this condition usually improves or goes away.
Notes
- Lactose intolerance is a condition in which the body has difficulty digesting milk and dairy products due to a lack of the enzyme lactase. nine0014
- The most common in the world is primary lactose intolerance, with it, with age, the activity of the LCT gene, which is responsible for the production of the enzyme, decreases.
- Secondary lactose intolerance occurs due to diseases or injuries in the intestines.
- Intolerance is also congenital, and sometimes develops due to premature birth. Atlas Genetic Test nine0014
In the following articles, we will talk about some misconceptions about lactose intolerance, such as why it is not related to allergies, and how you can live with this condition.
