How do u know if you are lactose intolerant?

If milk messes with your stomach, you might just assume you’re lactose intolerant and call it a day. But that’s not the only cause of dairy trouble, and knowing exactly why milk does a number on your gut will help you get a better handle on your symptoms.

First things first: Lactose intolerance isn’t the same thing as a milk allergy.

“Lactose intolerance is the inability to digest lactose, which is the sugar in milk. An allergy to milk is basically your immune system reacting to the proteins in milk, not the sugar,” James R. Baker, Jr., M.D., professor emeritus from the University of Michigan and CEO and CMO of Food Allergy Research & Education, tells SELF.

With lactose intolerance, your body essentially has an enzyme deficiency. It doesn’t make enough lactase—an enzyme in your small intestine that helps your body break down the sugar in milk. As a result, undigested lactose reaches your colon, where it reacts with gut bacteria. This digestive misstep can then lead to stomach discomfort.

A milk allergy, on the other hand, means your immune system has gone awry. It attacks milk proteins—namely, casein and whey—when they enter your body. It sees these proteins as potential threats. Your body may respond by producing chemicals called histamines, prompting an allergic reaction.

Your symptoms will provide a major clue about what’s troubling you.

People with a milk allergy often have an immediate reaction, within minutes. “Symptoms include mild ones such as skin rashes, hives, itchiness, and stomach pain. But they can also be serious, such as trouble breathing and poor blood circulation,” Scott H. Sicherer, M.D., professor of pediatrics, allergy, and immunology at Icahn School of Medicine at Mount Sinai, tells SELF. In fact, a food allergy can be life-threatening. It can result in anaphylaxis, a severe allergic reaction. And depending on your immune system, it might take only a dab of dairy for it to happen.

Symptoms of lactose intolerance often take longer to manifest—from many minutes to hours. That’s because it takes time for lactose to go through your gastrointestinal tract and reach your colon. Once it does, you may experience gas, bloating, an upset stomach, and diarrhea. These symptoms may be uncomfortable, but they aren’t life-threatening. And the severity usually depends on how much lactose you consume.

Your age is another indicator.

Another possible clue to your dairy problem is when you first started having symptoms. Most people with a milk allergy develop it as a child and outgrow it. Developing a food allergy as an adult is pretty uncommon. “Usually by the time you are an adult, your immune system has sorted itself out so it doesn’t react to things like food,” Dr. Baker adds.

So it’s more likely that a recently noted dairy reaction was lactose intolerance. Some people—about 10 to 15 percent in the U.S.—develop this problem. The exact reason is unclear, but “we know with aging the gut’s physiology declines,” Gerard E. Mullin, M.D., a board-certified gastroenterologist and associate professor of medicine at The Johns Hopkins Hospital, tells SELF.

And your family tree may provide some insight.

Allergies and lactose intolerance can be passed down through families. You may be more prone to developing a food allergy if family members have allergies, too. That includes any type of allergy, such as hay fever or eczema.

A drop in lactase is often genetic, although it may sometimes be caused by problems in the small intestine, such as an infection. Certain groups of people are more likely to suffer from lactose intolerance, including African-Americans, Hispanics, American Indians, and Asian Americans.

So what should you do if dairy is wreaking havoc on your gut?

The only way to be certain about what’s causing your reaction to dairy is to see your doctor. He or she will be able to make a diagnosis after asking about your symptoms and doing certain tests. To check for a milk allergy, your doctor may take a blood sample or prick your skin and put some milk on it to see if there is a reaction. You may also be asked to eat a bit of dairy in your doctor’s office. A breath test or stool sample may be used to diagnose lactose intolerance.

5 Signs you may be lactose intolerant

Lactose intolerance is a food intolerance caused by an inability to digest lactose, a sugar found in milk and dairy products. Unlike milk allergy, which involves an allergic reaction to a protein in milk, and happens after ingesting any amount of milk, lactose intolerance is due to not having enough lactase to digest the lactose sugars in milk and symptoms are related to the amount of lactose you ingest.

Here are 5 signs you may be lactose intolerant:

1. You develop symptoms of bloating, abdominal discomfort and cramps, or even vomiting, half an hour to 2 hours after eating foods containing lactose, such as milk, custard and yoghurt.

2. You get increased flatulence/gas after eating foods containing lactose.

3. Lactose-containing foods give you diarrhoea.

4. Your symptoms disappear after you remove lactose from your diet for 2 weeks.

5. You are of Asian descent, especially East Asia or China. People from these places may be lacking the enzyme lactase, which is the enzyme that the body uses to break down lactose. Lactose intolerance is also more common in people of African and South American descent.

Remember milk and other dairy foods are an important source of calcium, which is important for the health of your bones, so don’t remove these foods from your diet without seeking advice from your doctor or dietitian first.

If you think you may be lactose intolerant, consult your doctor who should be able to organise tests to diagnose your condition.

Lactose Intolerance Symptoms

The signs of lactose intolerance typically occur within 2 hours after consuming milk-based products.

If you are lactose intolerant, you will experience one or more of the following symptoms 30 minutes to two hours after consuming a milk-containing or milk-based product:

  • Abdominal bloating, pain, or cramps
  • Borborygmi (rumbling or gurgling sounds in the stomach)
  • Diarrhea
  • Flatulence, or gas
  • Nausea, which may be accompanied by vomiting

If you experience other symptoms, particularly hives and wheezing, immediately after consuming milk, you probably have a milk allergy — that is, you are allergic to the proteins in milk, and may not be lactose intolerant.

Dairy products are an important part of a balanced diet, providing the body with calcium, protein, and various vitamins, including A, B12, and D.

If you swear off dairy but don’t supplement your diet with foods containing these essential minerals and vitamins, you may experience complications, including a low bone-mineral density condition called osteopenia, which can lead to osteoporosis, a thin-bone disorder that increases your risks of fractures

Lactose Intolerance Tests

A simple method to see if you might be lactose intolerant is the so-called milk challenge.

Drink a glass of milk after not consuming any dairy products for several days; if you experience the hallmark symptoms of lactose intolerance listed above, you likely have the condition.

Your doctor also has a number of tests to see if you are lactose intolerant, including:

  • Hydrogen breath test
  • Lactose intolerance blood test
  • Intestinal biopsy
  • Stool acidity test
  • Genetic test

The hydrogen breath test is a simple and generally accurate technique to diagnose lactose intolerance.

Your doctor will ask you to drink a liquid with a known amount of lactose in it, and then later have you breathe into a device that measures the amount of hydrogen in your breath.

If you’re lactose intolerant, the bacteria in your intestines will digest the sugar and release the hydrogen and methane that the device can detect.

Alternatively, your doctor may perform a type of blood test called the lactose tolerance test.

Two hours after you drink a lactose solution, your doctor will draw and test your blood for glucose, a sugar produced when lactase breaks down lactose.

If your glucose levels didn’t rise or raised little, it means your body isn’t digesting the lactose.

An invasive intestinal biopsy is also available to diagnose lactose intolerance.

A gastroenterologist will use a long, thin surgical tool called an endoscope to take a sample of the lining of your small intestine. The sample will then be tested for lactase activity.

A stool acidity test is available for infants and children who cannot undergo other tests.

This test detects lactose intolerance by looking for a rise in stool acidity or pH, caused by bacteria fermenting lactose in the colon.

Finally, genetic tests can be used to diagnose lactose intolerance without provoking symptoms. All that’s required is a blood or saliva sample (consuming lactose isn’t necessary).

Dairy Intolerance

What is dairy?

Food produced from the milk of mammals is classed as dairy. The most common foods made from dairy are yoghurt, cheese, ice cream, and butter.

What is the difference between a milk allergy and a milk intolerance?

Many people suspect that allergies and intolerances are the same thing. However, the biological processes behind them are, in fact, totally different.

Food allergies are an immediate, potentially life-threatening, reaction to foods, such as milk. Symptoms may come on very quickly, often within minutes of eating the food. Approximately 2% of the adult population (UK figures) suffer from food allergies, and reactions are usually for life. If you have food allergies, your body produces IgE antibodies. Food-specific IgG (food intolerance) reactions, meanwhile, are usually delayed and are not life-threatening, but they can make life difficult. Food intolerances are not necessarily lifelong. You can find out more on the differences between allergy and intolerance here.

In addition to milk allergy and milk intolerance, lactose intolerance can also incite further confusion.

What is the difference between a milk intolerance and lactose intolerance?

The difference between lactose and milk intolerance differs greatly. While lactose intolerance is caused by a reaction to the sugar in milk, it is NOT the same as a milk allergy or milk intolerance.

Lactose intolerance is a digestive issue which is caused by an enzyme deficiency. People who suffer from lactose intolerance are unable to fully digest lactose, which is a type of sugar found in milk and dairy products. If you have a milk protein intolerance (defined by YorkTest as a food-specific IgG reaction), your body reacts negatively to the dairy protein. This means that you should look to remove all animal milks, such as cow, sheep or goat from your diet as the proteins are similar, unless they are separately tested.

Lactose intolerance can produce similar symptoms to a milk allergy and a milk intolerance; the reaction of a lactose intolerance can be delayed, similar to an IgG reaction. However, lactose intolerance is for life, similar to an allergy. If you suspect you have a lactose intolerance, please consult your GP where they may perform certain tests which could diagnose the deficiency, such as a hydrogen breath test.

What are the symptoms of being allergic to dairy?

A food allergy could be fatal, and a reaction is almost immediate, affecting around 2% of the population. Symptoms of a milk allergy may include:

  • Difficulty breathing
  • Skin rashes or hives
  • Swollen lips or tongue
  • Wheezing and chest tightness
  • Feeling sick, vomiting or diarrhoea
  • Itchy, red and watering eyes.

If you are concerned you may have an allergy to dairy, it is important to consult your GP.

What are the symptoms of dairy intolerance?

The symptoms of a milk protein intolerance (IgG) are wide-ranging, so it is important to discuss your symptoms with your GP before taking a closer look at your diet. Dairy intolerance symptoms could include, but are not limited to:

  • IBS symptoms – abdominal pain, bloating, excess wind
  • Skin complaints – eczema, psoriasis, urticaria (hives), rashes, itchy skin
  • Headaches and migraines
  • Weight gain
  • Anxiety and depression
  • Tiredness and fatigue
  • Joint pain
  • Respiratory problems
Can you outgrow a dairy intolerance?

Yes, it is possible to outgrow a milk intolerance, if this is an intolerance to the milk protein (IgG). However, please note that if you are diagnosed as lactose intolerant by your GP, you cannot outgrow this type of intolerance, but it can sometimes be helped by taking digestive enzymes.

How long does it take for dairy intolerance to show?

A food intolerance usually involves a delayed biological reaction. It is thought that a milk-specific IgG reaction can take between 2 to 72 hours to show.

How do you test for a milk intolerance?

There’s an easy way to determine if you are milk intolerant†. YorkTest, Europe’s leading provider in food intolerance† testing, has been providing IgG food intolerance† testing, which include milk-specific IgG antibody reactions, for over 35 years.

YorkTest’s FirstStep Test – £24.99 – This indicator test provides a simple yes or no result for a food intolerance†. If a positive reaction is identified, you can progress onto one of the full food intolerance programme† to see which individual food triggers you have, including milk-specific IgG. You will also be provided with post-result aftercare, including content material and nutritional consultation(s).

It is estimated that 45% of the population suffer from a food intolerance. YorkTest has found that the average person reacts to 4 to 5 different ingredients. Our Premium Food&Drink programme, for example, can assess the level of anti-milk antibodies in the blood, such as cow’s milk, sheep’s milk and goat’s milk. You may find you react to cow’s milk but tolerate other animal milks. Therefore, it’s always worthwhile to consider an IgG food intolerance† test before jumping into an elimination diet by yourself.

Please note that YorkTest’s programmes do not measure the levels of lactase, and therefore do not diagnose lactose intolerance. If the food intolerance test results indicate that you may have a milk intolerance, it does not mean that you have lactose intolerance, although you may wish to consult your doctor for further tests, as you may have both.

Which foods contain dairy?

There are many products which contain milk. Being aware of these is important when making changes to optimise your diet. The following list of ingredients should be avoided if you have a milk intolerance:

  • Milk (whole, semi skimmed, skimmed, UHT, condensed, powdered)
  • Cream (single, double, soured,
  • whipping, aerosol)
  • Cheeses (hard, soft and spreadable)
  • Butter and buttermilk
  • Crème fraiche
  • Fromage frais
  • Ice cream
  • Yoghurt
Does milk have other names?

Since December 2014, the Food Information Regulation classified 14 major food allergens which fall under the Food Safety Authority (FSA). It is a legal requirement that food businesses must provide allergen information in any food they sell or provide, making it easier for people with food allergies or intolerances to identify the trigger foods they need to avoid.

You will notice the main allergens on product packaging in bold and milk is one of them. However, milk can also take on other names that may not necessarily be in bold.

Milk can also be called:

  • Lactoglobulin
  • Lactalbumin
  • Casein
  • Caseinate
  • Lactose

If you notice these names on product packaging, it’s best to steer clear of these ingredients if you are actively avoiding milk products.

What are dairy-free foods?

If you have a milk intolerance, there’s no need to worry. Now more than ever, there are plenty of milk-free and dairy-free options available in major supermarkets, coffee shops, and restaurants. To ensure you maintain a balanced diet which provides protein, calcium and fat-soluble vitamins, you can supplement your diet with a variety of dairy alternatives. These include:

  • Coconut milk
  • Rice milk
  • Oat milk
  • Sunflower or olive oil spreads
  • Soya cheese
  • Nut cheese
  • Almond or hazelnut milk
  • Hemp milk
  • Soya milk
How do I get enough calcium on a milk-free diet?

Milk can be an important source of calcium and, therefore, it is natural to become cautious when removing this from your diet, due to a risk of Osteoporosis or calcium/Vitamin D deficiency.

If your results show you have a milk intolerance, YorkTest’s Nutritional Therapists are here to help. Nutritional consultations are provided with any of YorkTest’s full food intolerance† programmes which gives you a worthwhile opportunity to discuss a range of alternatives not listed above that could support with your elimination diet and your calcium levels. They will also give you bespoke advice on what foods and drinks you need to avoid which contain milk/dairy that are currently in your diet.

Making health happen

Did you know that 4 out of 5 people who followed one of our full programmes noticed an improvement in their symptoms? You can check out our 2017 customer survey for more information. To give you an insight into our customer journeys, we’ve selected a few snippets below whose lives were improved after eliminating milk from their diet amongst other trigger foods. They’ve found their food fingerprint with YorkTest. Is it time to discover yours?

Milk & Dairy Allergy

Avoidance of milk or items containing milk products is the only way to manage a milk allergy. People who are allergic to milk and the parents of children who have this allergy must read ingredient labels very carefully.

Milk is one of eight allergens with specific labeling requirements under the Food Allergen Labeling and Consumer Protection Act of 2004. That law requires manufacturers of packaged food products sold in the U.S. and containing milk as an ingredient to include the presence of milk or milk products, in clear language, on the ingredient label.

There are two main types of milk protein — casein and whey. Casein, the “solid” part of milk, comprises about 80 percent of milk protein. Whey proteins, found in the liquid part of milk, make up the other 20 percent. Milk proteins are found in many foods, including all dairy products, and in many places where they might not be expected. For example, some canned tuna, sausage, meats and other nondairy products may contain casein. Beverage mixes and body-building and energy drinks commonly contain whey. Milk protein has also been found in some chewing gum.

Some companies may voluntarily include information that their food products “may contain traces of milk” or that they are manufactured in a facility that also processes milk, though such advisory statements are not required by law.

Allergies to food (including milk) are the most common causes of anaphylaxis, a potentially life-threatening allergic reaction. Symptoms include swelling of the airways, impairing the ability to breathe, and a sudden drop in blood pressure, causing dizziness and fainting. An allergist will advise patients with a food allergy to carry an auto-injector containing epinephrine (adrenaline), which is the only treatment for anaphylactic shock, and will teach the patient how to use it. If a child has the allergy, teachers and caregivers should be made aware of his or her condition as well.

Some people with this allergy can tolerate foods containing milk that has been extensively heated, such as a baked muffin. Still, people with an allergy to milk protein should consult an allergist before determining whether they should completely avoid milk and other dairy products.

Milk is a fairly easy ingredient to substitute in recipes. Most recipes calling for milk can be just as successful by substituting the equivalent in water, juice, or soy or rice milk. If your infant is allergic to milk, talk to your pediatrician about which formula to use. Often, an extensively hydrolyzed elemental formula or a casein-hydrolysate formula is recommended for milk allergy in infants, as the proteins in these formulas have been extensively broken down. Alternatively, your infant’s doctor may recommend a soy-based formula.

Treatment & medication

Cutting lactose out of the diet is an option, but patients should make sure they aren’t depriving themselves of calcium and vitamin D, Balzora said.

A study published in the June 2017 issue of the Journal of Nutrition found that those with lactose intolerance that cut milk out of their diet have lower levels of vitamin D in their blood. This study of 1,495 Canadian men and women also found that those who cut out milk were also shorter.

Over-the-counter pills or drops that contain lactase can be taken before meals to help alleviate or eliminate symptoms. For example, Lactaid pills or Lactaid milk allow many people to process dairy products without any difficulty, Balzora said. Some people find that taking probiotics can help them digest lactase better, but Lactaid is really the standard, Balzora said.

However, according to the Mayo Clinic, these products do not help all patients. Adults who are lactose intolerant can ultimately recondition their digestive system to tolerate up to 8.5 fluid oz. (250 milliliters) of milk — about a glass — if they drink the milk in gradually increasing amounts. According to a 21-day intervention study conducted in 2000, most people who do this will experience minimal or no discomfort.

A 2017 study by scientists at the North Carolina School of Medicine and North Carolina State University found that probiotics may also be a useful treatment. The study, published in the journal Proceedings of the National Academy of Sciences, found that 70 percent of those that took prebiotics for 35 days had reduced abdominal pain when they resumed drinking milk. Ninety percent of the subjects showed a significant increase in lactose fermenting bacteria, as well.

Coping strategies

Lactose intolerance can be treated with simple dietary changes. The most straightforward way is for a person to reduce the amount of milk or daily products in his or her diet. Also, it may help to divide daily milk and dairy products into several small portions and consume them with other foods. Processed dairy such as yogurt and cheeses are usually better tolerated, because the lactose has been partially metabolized by bacteria during their preparation.

Foods high in lactose, according to The Cleveland Clinic, are:

  • Milk, milkshakes and other milk-based beverages
  • Foods made with milk
  • Whipping cream and coffee creamer
  • Cheese
  • Ice cream, ice milk, sherbet
  • Puddings, custards
  • Butter
  • Cream soups, cream sauces

There are many products on the market that are lactose-free. This is a good option for those that don’t want to give up their favorite milk products. There are more options on the way. The lactose-free food market is predicted to grow 11.10 percent between 2017 and 2021.

There are also other options, such as rice, soy and almond milk, that can be used as an alternative to cow’s milk. Additionally, there are some milk products that can be easier to digest. According to the NIH, they include:

  • Buttermilk and cheeses
  • Fermented milk products, like yogurt
  • Goat’s milk
  • Ice cream
  • Milkshakes
  • Aged or hard cheeses

Additional reporting by Alina Bradford, Live Science Contributor.

Additional resources

  • NIH: Lactose Intolerance
  • The Mayo Clinic: Lactose Intolerance
  • The National Institute of Diabetes and Digestive and Kidney Diseases Health Information Center: Lactose Intolerance

When you’re feeling too ill to eat, or have indigestion, what could be better than a gentle, thick glass of milk to settle your stomach? It’s soothing to drink, and at least you are getting something nutritious inside you. This remedy has been around for years in countries where milk is popular. Until the 1980s, doctors would sometimes recommend milk to patients with duodenal ulcers (in the intestine just beyond the stomach) to help ease their discomfort.

Milk is in fact slightly acidic, but far less so than the gastric acid naturally produced by the stomach. So it was long thought that milk could neutralise this stronger acid and relieve the pain. Milk does help provide a temporary buffer to gastric acid, but studies have shown that milk stimulates acid production, which can make you feel sick again after a short period of relief.

In 1976, ten hardy research participants put themselves forward to test this out. They had their stomachs emptied and were then fed milk through a tube up their nose. An hour later the contents of their stomachs were sucked out again and then gastric acid secretion was measured every five minutes. The researchers found that milk caused an increase in the secretion of gastric acid for the next three hours, which could explain why people with ulcers typically experience pain a few hours after a meal.

It’s not just milk, though. Studies comparing coffee, tea, beer and milk found they all stimulated the secretion of acid. Beer and milk have the greatest effect, which suggests, somewhat surprisingly, that the pH of a drink is irrelevant when it comes to acid production.

So what is the ingredient in milk that causes the stomach to produce acid? Researchers in the 1976 study looked at fat by comparing whole, low-fat and fat-free milk. All increased acid secretion. How about calcium? When they tried the experiment using low-calcium milk, less acid was produced, but there was an exception. The patients who had evidence of duodenal ulcers, but were not currently experiencing symptoms, produced more acid.

The other ingredient which might stop milk from settling your stomach is the milk protein casein. It is thought it either stimulates the release of the hormone gastrin, which in turn controls the production of gastric acid, or it stimulates directly the cells in the stomach lining, known as parietal cells, to release acid.

Either way, milk is no longer recommended for people with ulcers because it might do the opposite of soothing them. It could make them worse. In 1986 patients with duodenal ulcers spent four weeks in hospital on medication as part of a controlled trial. One unlucky group was assigned to drink only milk – two litres a day in total, with added sugar if they preferred. The other group ate the usual hospital diet and both groups were also offered additional fruit, so there was a similar total intake of calories between the two groups. At the end of the four weeks each patient underwent an endoscopy to examine their ulcers. Significantly more people on the standard diet had ulcers that had healed, while fewer than expected got better in the milk-drinking group. Milk appeared to hinder the healing process.

If you are well, drinking milk is still encouraged, as it is a good source of protein and calcium. But could very large quantities of milk present a problem? In 1980, 21,000 adults in the city of Tromso in Norway were invited to join a health study where they would be followed for seven years, during which time 328 developed peptic ulcers (an umbrella term covering duodenal and stomach ulcers). They found that heavy milk drinkers (defined as four or more glasses a day) were more likely to develop an ulcer, especially amongst the men. Again, it made no difference whether the milk was full fat or skimmed. So was the milk causing the ulcers? The difficulty here is that some people with pain drink milk to ease the symptoms temporarily, so perhaps they were consuming milk as a result of the ulcer. But the risk was also high in those drinking large quantities of milk, despite not having symptoms, so it’s hard to disentangle the causality.

So although milk temporarily coats the lining of the stomach, buffering the acid in your stomach and making you feel a bit better, the relief might last for only twenty minutes or so. In other words milk may have many benefits, but settling an upset stomach isn’t one of them.

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Does your stomach churn after you drink milk? Do you have diarrhea soon afterward? If so, you may be lactose intolerant.

The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) estimates that 30 to 50 million Americans are lactose intolerant.

Being lactose intolerant means you can’t digest lactose—the natural sugar found in milk and other dairy products. People who cannot digest lactose have a shortage, or deficiency, of an enzyme called lactase, which is produced in the small intestine. Lactase breaks down milk sugar into two simpler forms of sugar, which are then absorbed into the bloodstream.

Intolerance is Not Allergy

Lactose intolerance is not the same as a milk allergy, says Kavita Dada, Pharm.D., a senior health promotion officer in the Food and Drug Administration’s (FDA’s) Division of Drug Information. “For most people with lactase deficiency, it’s a discomfort.”

People who have trouble digesting lactose can learn which dairy products and other foods they can eat without discomfort and which ones they should avoid.

But a food allergy—an abnormal response to a food triggered by the immune system—can be life-threatening. People with food allergies must avoid certain foods altogether. People with food intolerances can often eat small amounts of the offending foods without having symptoms.


When there is not enough lactase to digest the lactose in the foods a person eats or drinks, the person may have

  • gas
  • stomach cramps
  • bloating
  • nausea
  • diarrhea

These symptoms typically occur within 30 minutes to two hours after consuming food containing lactose. Some illnesses can cause these same problems, but a health care professional can do tests to see if the problems are caused by lactose intolerance or by another condition.

Who Becomes Lactose Intolerant?

Lactose intolerance is more common in some ethnic groups than others. NIDDK estimates that up to 75% of all adult African Americans and Native Americans and 90% of Asian Americans are lactose intolerant.

As people age, their bodies produce fewer lactase enzymes, so most people don’t have symptoms until they are adults.

Most people inherit the condition from their parents. Lactose intolerance is not very common in children under two years of age, unless the child has a lactase deficiency because of an injury to the small intestine. If you think your infant or child may be lactose intolerant, talk to your child’s pediatrician.

Managing Lactose Intolerance

There is no treatment to make the body produce more lactase enzyme, but the symptoms of lactose intolerance can be controlled through diet.

Most older children and adults do not have to avoid lactose completely. People have different levels of tolerance to lactose. Some people might be able to have a tablespoon of milk in a cup of coffee with little or no discomfort. Others have reactions that are so bad they stop drinking milk entirely. Some people who cannot drink milk may be able to eat cheese and yogurt—which have less lactose than milk—without symptoms. They may also be able to consume a lactose-containing product in smaller amounts at any one time.

Common foods with lactose are

  • milks, including evaporated and condensed
  • creams, including light, whipping, and sour
  • ice creams
  • sherbets
  • yogurts
  • some cheeses (including cottage cheese)
  • butters

Lactose may also be added to some canned, frozen, boxed, and other prepared foods such as

  • breads and other baked goods
  • cereals
  • mixes for cakes, cookies, pancakes, and biscuits
  • instant potatoes, soups, and breakfast drinks
  • lunch meats (other than Kosher)
  • frozen dinners
  • salad dressings
  • margarines
  • candies and other snacks

Dietary supplements with lactase enzyme are available to help people digest foods that contain lactose. However, FDA has not formally evaluated the effectiveness of these products, and you may want to ask your doctor if these supplements are right for you.

Look at Labels

“Lactose-free” or “lactose-reduced” milk and other products are widely available in grocery stores. These products may be fortified to provide the same nutrients as their lactose-containing counterparts.

There is no FDA definition for the terms “lactose free” or “lactose-reduced,” but manufacturers must provide on their food labels information that is truthful and not misleading. This means a lactose-free product should not contain any lactose, and a lactose-reduced product should be one with a meaningful reduction. Therefore, the terms lactose-free and lactose-reduced have different meanings, and a lactose-reduced product may still contain lactose that could cause symptoms.

Lactose-free or lactose-reduced products do not protect a person who is allergic to dairy products from experiencing an allergic reaction. People with milk allergies are allergic to the milk protein, which is still present when the lactose is removed.

Look at the ingredient label. If any of these words are listed, the product probably contains lactose:

  • milk
  • cream
  • butter
  • evaporated milk
  • condensed milk
  • dried milk
  • powdered milk
  • milk solids
  • margarine
  • cheese
  • whey
  • curds

Highly sensitive individuals should also beware of foods labeled “non-dairy,” such as powdered coffee creamers and whipped toppings. These foods usually contain an ingredient called sodium caseinate, expressed as “caseinate” or “milk derivative” on the label, that may contain low levels of lactose.

Testing for Lactose Intolerance

A doctor can usually determine if you are lactose intolerant by taking a medical history. In some cases, the doctor may perform tests to help confirm the diagnosis. A simple way to test at home is to exclude all lactose-containing products from your diet for two weeks to see if the symptoms go away, and then reintroduce them slowly. If the symptoms return, then you most likely are lactose intolerant. But you may still want to see your doctor to make sure that you are lactose intolerant and do not have a milk allergy or another digestive problem.

Tips for Consumers

  • If you are lactose intolerant, try lactose-free milk or dairy products lower in lactose, such as yogurt and cheese. You may be able to consume dairy products in small amounts without symptoms.
  • Consume milk or other dairy products with other foods. This helps slow down digestion, making it easier for your body to absorb lactose.
  • If you’re eating few or no dairy products, ask your doctor or dietitian if you are getting enough calcium in your diet. You may need to take dietary supplements with calcium to keep your bones healthy.

Raw Milk and Lactose Intolerance

FDA warns consumers not to drink raw, or unpasteurized, milk. “Raw milk advocates claim that pasteurized milk causes lactose intolerance,” says John Sheehan, Director of FDA’s Division of Plant and Dairy Food Safety. “This is simply not true. All milk, whether raw or pasteurized, contains lactose, and pasteurization does not change the concentration of lactose nor does it convert lactose from one form into another.”

Raw milk advocates also claim that raw milk prevents or cures the symptoms of lactose intolerance. Arguing that raw milk contains Bifidobacteria, they claim these microorganisms are beneficial (probiotic) and create their own lactase, which helps people digest the milk.

“This is not true, either,” says Sheehan. “Raw milk can contain Bifidobacteria, but when it does, the bacteria come from fecal matter (animal manure) and are not considered probiotic, but instead are regarded as contaminants.”

Drinking raw milk will still cause uncomfortable symptoms in people who are correctly diagnosed as being lactose intolerant. But worse than this discomfort are the dangers of raw milk, which can harbor a host of disease-causing germs, says Sheehan. “These microorganisms can cause very serious, and sometimes even fatal, disease conditions in humans.”

Lactose intolerance

Plenty of people get a stomachache after eating a huge ice cream sundae. But if you get a stomachache every time you eat pizza or drink milk, you could have lactose intolerance (say: LAK-tose in-TAH-luh-runtz).

Lactose intolerance means that you have trouble digesting lactose, which is the sugar in dairy foods. (Lactose intolerance isn’t the same thing as a milk allergy, which happens when your immune system acts as though anything made from milk is a threat to your body.)

These days, there are lots of ways for people with lactose intolerance to deal with it. Keep reading to learn more, including:

  • Symptoms of lactose intolerance
  • Diagnosing lactose intolerance
  • Living with lactose intolerance

Symptoms of lactose intolerance top

Lactose intolerance can start suddenly, even if you’ve never had trouble with dairy products before. Symptoms usually start a half-hour to two hours after eating or drinking something with lactose. Symptoms include:

  • Stomach cramps
  • Bloating
  • Gas
  • Diarrhea
  • Nausea

If you think you may have lactose intolerance, see your doctor.

Diagnosing lactose intolerance top

To diagnose lactose intolerance, your doctor may ask you some questions and do a physical exam. The next step may be for you to avoid eating foods with lactose for a while and see if you feel better.

The doctor may also do some tests. One common test checks your breath for a substance your body makes if it is not digesting lactose well. Another possible test is called an endoscopy. A thin tube is placed down your throat to get a better sense of what’s going on inside your digestive system. It may be a little uncomfortable, but it shouldn’t hurt.

Living with lactose intolerance top

There is no cure for lactose intolerance, but there are lots of ways to live well with it and enjoy yummy foods. Try these suggestions:

  • Talk to your doctor about pills and drops made from lactase, which is the enzyme that helps you digest the lactose in milk and milk products.
  • Drink lactose-reduced and lactose-free milk, which can be found in most grocery stores. Look for products like lactose-reduced cottage cheese.
  • Try eating dairy again by adding small amounts at first and slowly adding more.
  • Have milk along with a meal or other foods, such as cereal, rather than alone.
  • Try dairy foods that have less lactose than milk, since they may not bother your stomach as much. Try yogurt and cheeses like cheddar and Swiss.

If you can’t comfortably eat any lactose, learn to read food labels. Even products like lunch meats and cereal may have products made from milk, such as whey. You also can look for alternatives to dairy, such as rice milk, almond milk, soy yogurt, and cream cheese made from tofu.

Consider working with a dietitian, who can suggest foods to eat that are good for your health and won’t upset your stomach.

Lactose intolerance and bone health

If you don’t eat dairy products, it can be hard to get enough calcium and vitamin D. These nutrients are very important for building strong bones.
If dairy bothers your stomach, try the bulleted tips above to eat some dairy products. You also can look for other sources of calcium and vitamin D, such as calcium-fortified orange juice. Check out the %Daily Value on Nutrition Facts labels to see how much of these nutrients are included. Girls need 1,300 milligrams of calcium (which means you need to eat enough to add up to 130% of the Daily Value) and 600 International Units of vitamin D per day (which is 100% of the Daily Value). If you can’t get enough calcium and vitamin D from foods and drinks, your doctor may recommend a supplement.

Content last reviewed November 05, 2013
Page last updated January 13, 2014


Deciding on your own to avoid foods to alleviate adverse symptoms should be weighed against the consequences of eliminating dietary factors and their related nutrient profiles. In the case of dairy foods, those consequences could be significant for your health and, given the apparent scale of the avoidance behaviour, for society in the long term.

Improper and self-diagnosis have bad consequences

The symptoms of Lactose Intolerance are straightforward and quite noticeable: gas, diarrhea, cramps, flatulence, and the rumbling of gas through the intestines that’s called borborygmi. Problem is, these are also the symptoms from dozens of problems, ranging from reactions to other foods to some truly serious diseases! The aim of this Italian study was to investigate if self-diagnosis may influence dairy consumption. Results showed that 22.2% of the responders based in Campania (a region in Southern Italy) do not drink fluid milk on a regular basis, and 18.1% drink lactose-free milk mainly to avoid gastrointestinal symptoms. The vast majority of the population chose to avoid milk consumption without undergoing a breath test for lactose intolerance or ask a doctor.

You can still eat dairy, like yogurt!

Talk to your doctor! He can give you an objective and definitive diagnosis. If you have felt digestive problems after consuming milk or another dairy product, it is not necessarily due to the lactose. Furthermore, not all dairy products are the same when it comes to lactose. Yogurt and low lactose options had the particular characteristic of being well tolerated by people who find lactose difficult to digest. Eating at least one yogurt a day gives you part of the calcium (15% to 20%) that your bones need each day throughout your life. So, check with your doctor first!

Source: Zingone et al., Nutrition journal 2017 ; 33 : 322-325.

How long do lactose intolerance symptoms last?

We’ve been asked many times: How long do lactose intolerance symptoms last? It can be a tricky question. The easy answer is: it all depends on your body.

The more thorough response about lactose intolerance symptoms would be: are you sure it’s lactose intolerance? Let’s take a look at what intolerances are and a few signs and symptoms you may experience.

Food intolerance involves the digestive process. Symptoms of an intolerance can come on gradually and is not life threatening. If eating a certain food (too much of that certain food) irritates your stomach or you’re not digesting it properly you may have food intolerances. The symptoms can show up 30 minutes to 2 hours later. These reactions are very different than food allergies.

Symptoms of food intolerances:

  • Gas (food baby)
  • Bloating
  • Headaches
  • Heartburn
  • Flatulence (passing gas)
  • Fatigue

Food allergies are different. They are an immune response. More specifically and IgE response. In the case of a true food allergy the symptoms come on very quickly. Just the smallest amount of a certain food can initiate a reaction and they can be life threatening. These symptoms happen suddenly and most often before a 30-minute mark.

Symptoms of food allergies:

  • Hives
  • Rashes
  • Shortness of Breath
  • Drop in Blood Pressure
  • Itchy Skin

On one side of the spectrum you have intolerances on the opposite side you have food allergies. In the middle you’ll find sensitivities. This too is an immune response but it is delayed not immediate. Meaning, delayed reactions will happen after a 3 hour mark but can even happen 3 weeks or 3 months later. The signs and symptoms can be some of the same as both the intolerance and the allergy.

Symptoms of food sensitivities:

  • Gas and bloating
  • Fatigue
  • Itchy Skin
  • Headaches
  • Joint and muscle pain
  • Indigestion
  • Brain Fog
  • Swelling
  • Puffy eyes
  • Eczema/Acne
  • Feeling “sick all over” but really can’t find supporting evidence

How can you tell the difference? When it comes to intolerances versus sensitivities you can run a food/chemical sensitivity test. The LRA by ELISA/ACT test can look at more than 500 different items and how your white blood cells respond. This is the most accurate way to tell if you have sensitivities. There are folks out there that encourage a rotation or elimination plan. This just isn’t accurate enough.

Think about this: you suspect you have a lactose intolerance because three hours after you eat vanilla ice cream you get the most horrendous belly bloating and gas. Your stomach swells so big you look six months pregnant and the pain is excruciating. You decide to stop eating vanilla ice cream. But, desperate for an ice cream fix you buy vanilla ice cream made from almond milk only to have the same thing happen. Now you’re curious and try vanilla ice cream made from coconut milk and it happens again. You finally agree to give food/chemical sensitivity testing a try and the results come back with sensitivity to vanilla, carrageenan, and propylene glycol among other things. All of these could be ingredients in cow dairy ice cream products and alternative milk ice cream products. These reactive items can be in other foods (or meals) you’re eating and because of the delay in symptoms you may not be able to pinpoint the exact food that is causing the disturbance. Eliminating foods and substituting without definitive answers and guidance can turn to a wild goose chase and extreme frustration.

So, how long do lactose intolerance symptoms last? As long as it takes your body to digest and eliminate. For some people that could be 12 hours for others it could be much longer. Intolerance means inability to tolerate (or digest). Your body will force the undigested cow dairy product through the system and you may experience the pain and discomfort as long as it takes you the food from point A to point B.

To determine your digestive transit time (time to digest and eliminate), it can be tracked by using enough activated charcoal capsules appropriate for your weight. Jot down the start time and finish time. The finish time is when you see the activated charcoal in your stool. Optimal digestive transit time is 12-18 hours.

Whether you have intolerances or sensitivities: why guess when you can test? Take simple steps to control your health and wellness outcomes. Choose your test and get tested.

For more information on lactose intolerance, click here.

The Alkaline Way is a personalized eating and lifestyle plan from world-renowned researcher Russell Jaffe MD, PhD, CCN.

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