Milk allergy or intolerance

Lactose Intolerance or Milk Allergy: What’s the Difference?

There’s a lot of confusion surrounding lactose intolerance and milk allergy — the terms may sound similar, but they actually describe two different digestive problems, and one is more severe than the other.

Lactose intolerance is caused by not having enough of the enzyme lactase, which is needed to break down lactose, the sugar found in milk and other dairy products. Milk allergy is a true food allergy caused by an allergic reaction to the protein in milk.

“Lactose intolerance and milk allergy are very different entities,” explains Amy E. Barto, MD, a gastroenterologist at the Lahey Clinic in Burlington, Mass. “Milk allergy usually shows up early in life. Lactose intolerance is more common, takes longer to develop, and can occur at any time of life.”

Symptoms of Lactose Intolerance vs. Milk Allergy

Lactose intolerance can be genetic, or it can be caused by damage to the small intestine due to a viral or bacterial infection, Dr. Barto explains. It’s also fairly common, and more so in certain populations. “About 80 to 90 percent of African-Americans have lactose intolerance, and it is also very common in Asians and Native Americans,” says Barto. “It is also important to remember that lactose intolerance increases with age and is quite common in the elderly.” It’s estimated that 30 to 50 million Americans have lactose intolerance.

You’ll typically feel lactose intolerance symptoms between 30 minutes and two hours after ingesting milk or a dairy food. Symptoms may include:

  • Stomach pain
  • Gas and bloating
  • Nausea
  • Diarrhea

Milk allergy usually refers only to cow’s milk, although you may also be allergic to other types of milk, including soy. Although milk allergy is most common in infants and children, it can develop at any age. Milk allergy is the most common food allergy in children, affecting more than 2 percent of children who are under the age of 3. Many children outgrow milk allergies by age 5.

The food allergy reaction to milk can begin within minutes or can be delayed for several hours. Symptoms may include:

  • Stomach pain
  • Nausea
  • Diarrhea
  • Skin rash
  • Swelling of the lips or throat
  • Trouble breathing

Diagnosing Lactose Intolerance and Milk Allergy

Lactose intolerance can typically be distinguished from milk allergy by less severe symptoms and a person’s history of problems with dairy, but sometimes doctors aren’t able to differentiate the two right away. “Your doctor may ask you to keep a food diary, avoid dairy for a while, and then reintroduce it,” says Barto. “If in doubt, there are lab tests that can help make the diagnosis.”

Tests include:

  • Hydrogen breath test. Undigested lactose produces high levels of hydrogen gas in your breath. Doctors can diagnose lactose intolerance by measuring this hydrogen after you drink a lactose-loaded beverage.
  • Stool acidity test. Undigested lactose also increases the amount of acid in the stool. Doctors may use this test to diagnose lactose intolerance in young children.
  • Food allergy testing. If your doctor suspects a milk allergy, you may be sent to an allergist for skin testing or have a blood sample drawn for laboratory allergy testing.

Can You Eat Dairy With Lactose Intolerance or Milk Allergy?

For both of these conditions, you’ll need to avoid or limit most dairy products. “But it is important to make sure you are getting enough calcium,” says Barto.

If you have lactose intolerance, you may be able to tolerate small amounts of dairy. You can try hard cheeses and yogurt products, which tend to be lower in lactose than milk. There are also a variety of dairy-free foods that are high in calcium, including spinach, almonds, and dark leafy green vegetables.

If you have milk allergy, you need to read labels and avoid foods that have any dairy, including the ingredients casein, whey, lactulose, lactalbumin, and ghee.

If you or your child has symptoms that may be due to milk allergy or lactose intolerance, talk with your doctor. He or she can diagnose the problem and advise you on how best to avoid dairy while maintaining good nutrition, which is important no matter how young or old you are.

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Lactose intolerance and cow’s milk allergy are two different conditions (Photo: Adobe. Do not use without permission)

Lactose intolerance and cow’s milk allergy often get mixed up. Lactose intolerance is caused by a lack of an enzyme that helps you to digest the sugar in milk. Cow’s milk allergy, on the other hand, is an adverse immune reaction to proteins found in milk. They are completely unrelated conditions except that they share a common cause – cow’s milk and dairy products.

After returning from the Beagle expedition in 1836, Charles Darwin wrote: “I have had a bad spell. Vomiting every day for eleven days, and some days after every meal.”

Darwin struggled for more than 40 years with long bouts of vomiting, stomach cramps, headaches, severe tiredness, skin problems, and depression. Researchers now think that he had lactose intolerance, and his case is a good example of how easily it can be missed or misdiagnosed.

What is lactose?

Lactose is the sugar in mammal’s milk. In order to release its energy, it must be broken down into its constituent simple sugars – glucose and galactose – so they can be absorbed. This task falls to an enzyme called lactase, produced by cells lining our small intestines

If your body doesn’t produce this enzyme, then lactose travels to the large intestine where it is fermented by gut bacteria, producing hydrogen and a range of potential toxins.

This is ‘lactose intolerance’, and most symptoms result from the production of gases and toxins by these gut bacteria. Symptoms include a bloated and painful stomach, wind, diarrhea, and, on some occasions, nausea and vomiting.

Other symptoms can include muscle and joint pain, headaches, dizziness, lethargy, difficulty with short-term memory, mouth ulcers, allergies, irregular heartbeat, sore throat, increased need to pass urine, acne, and depression.

Even more worrying is that the toxins produced by bacteria may play a key role in diseases such as diabetes, rheumatoid arthritis, multiple sclerosis, and some cancers.

Dairy products contain lactose – which many are intolerant to (Photo: Adobe. Do not use without permission)

Lactase and weaning

Everyone naturally produces lactase when they are babies – without it we couldn’t drink our mother’s milk. However, all mammals and the vast majority of people stop producing it soon after weaning – for us, around the age of two. This is the normal state for most people – around 70 percent of the world’s population, in fact.

In Northern Central Europe, lactose intolerance affects between two and 20 percent of people, rising to 40 percent in Mediterranean countries – most common in Italy where it affects 56-70 percent in some regions.

Highest rates are seen in Africa, where it affects 65-75 percent of people, and Asia, where more than 90 percent of people are lactose intolerant.

Lactase persistence

So why are some people able to digest lactose after weaning and others not?

‘Lactase persistence’ originates from a genetic mutation that occurred among a small number of European and African pastoral tribes within the last 5,000-10,000 years – in evolutionary terms, this is very recent history.

It provided a selective advantage to populations using dairy products, enabling them to live long enough to have children. The average life expectancy was probably little more than 25 years, but this meant the ability to digest lactose could be passed on to subsequent generations.

Descendants of these people are still able to consume cow’s milk without suffering the symptoms of lactose intolerance. It doesn’t mean, however, that it’s good for them.

Ditching lactose

The treatment for lactose intolerance is straightforward: avoid lactose. It means cutting out all cow’s milk, and other dairy foods and checking labels as lactose is added to many unlikely foods, including bread, breakfast cereals, salad cream, mayonnaise, biscuits, chocolate, cake, crisps, instant soup and some processed meats, such as sliced ham.

The word ‘lactose’ will not necessarily be listed on food labels so look out for things like dried milk or whey powder.

Lactose is also used as a filler in many types of medication and while this may not trigger symptoms in most people with lactose intolerance, it can cause problems in some. Check with your doctor and request lactose-free tablets.

Cow’s milk allergy

Cow’s milk allergy is very different to lactose intolerance. An allergic reaction is when the body’s immune system launches an inappropriate response to substances mistakenly perceived as a threat.

Common triggers include latex, detergent, dust, pollen or certain proteins in food. In cow’s milk, it is the protein casein that causes most problems, but whey protein can also trigger a reaction in some people.

General symptoms include inflammation, sneezing, runny nose, itchy eyes, and so on, giving rise to the classic allergies – asthma, eczema, hay fever, and urticaria (skin rash or hives). Because cow’s milk allergy is linked to many conditions – including asthma and eczema – it’s always useful to consider it when treating them.

Dairy can cause health issues for a range of people (Photo: Adobe. Do not use without permission)

Common allergy

Cow’s milk allergy is one of the most common food allergies in children, affecting between two and 7.5 percent of infants under one, although some grow out of it by the age of five.

Symptoms include an itchy rash or swelling, stomach ache, vomiting, colic, diarrhea or constipation, and a runny nose. Symptoms can appear almost immediately or up to 72 hours after consuming cow’s milk protein. This makes it difficult to diagnose.

A big problem affecting infants can be gastrointestinal bleeding resulting from cow’s milk allergy. Blood loss often occurs in such small quantities that it goes unnoticed but over time can cause iron-deficiency anemia.

Scientists suggest that blood loss associated with cow’s milk consumption during infancy may affect 40 percent of otherwise healthy infants. Exactly how cow’s milk causes blood loss from the intestines is unclear but it’s generally agreed that it is probably an adverse immune (allergic) reaction.

However, because healthy infants lose some blood anyway and cow’s milk-induced bleeding is clinically silent and shows no other symptoms, it’s difficult to say how many more infants than the widely accepted figure of less than 10 percent may actually be allergic to cow’s milk.

Not good for kids

Regardless of these problems, it’s simply not a good idea to give cow’s milk to children at all as it contains virtually no iron but does contain potent inhibitors, reducing the body’s ability to absorb iron from other foods in the diet.

The high protein, sodium, potassium, phosphorus, and chloride content of cow’s milk present what is called a ‘high renal solute load’.

Unabsorbed solutes from the diet must be excreted by the kidneys and this can place a strain on immature kidneys, forcing them to draw water from the body thus increasing the risk of dehydration. This is why most health bodies say that cow’s milk should not be given to children under 12 months of age.

Developing allergies

Although a lot of food allergies start in childhood, you can develop them as an adult, too. Cow’s milk allergy in adults is relatively rare, but symptoms tend to be much more severe than in children when they do occur, with reactions being triggered by amounts as low as 0.3 milligrams of cow’s milk protein.

The most severe type of allergic reaction (anaphylactic shock) may involve difficulty in breathing, a drop in blood pressure, and ultimately heart failure and death.

Occasionally, cow’s milk allergy can cause severe symptoms that come on suddenly, such as swelling in the mouth or throat, wheezing, coughing, shortness of breath, and difficulty breathing. In such cases, immediate medical help must be sought.

There are a range of dairy-free alternatives available (Photo: Adobe. Do not use without permission)

Avoiding cow’s milk

The only reliable treatment for cow’s milk allergy is to avoid all cow’s milk and dairy products, including milk, milk powder, milky drinks, cheese, butter, margarine, yogurt, cream, and ice-cream.

Products with hidden milk content should also be avoided – look out for: casein, caseinates, hydrolyzed casein, skimmed milk, skimmed milk powder, milk solids, non-fat milk, whey, and milk solids.

People with cow’s milk allergy face a similar problem as those avoiding lactose – milk-based ingredients can be difficult to avoid as they are commonly used in the production of so many foods. It can seem a daunting prospect, having to read the ingredients labels, but most supermarkets now produce product ‘free-from’ lists, and many have their own-label range.

There are even iPhone apps available now to help you identify ingredients by scanning the product bar code. Soya ice creams, spreads and yogurts, and dairy-free cheeses are just some ‘free-from’ examples.

The calcium myth

It’s a myth that people who avoid dairy miss out on calcium – there are many excellent non-dairy sources, including green leafy vegetables (spinach is a relatively poor source as it contains oxalate which binds calcium), dried fruits, nuts and seeds, calcium-set tofu and calcium-fortified soy milk. Remember, 70 percent of the world’s population don’t do dairy – so you’re not alone.

Dairy consumption in the UK is in decline as the market for plant-based milks, vegan cheese, yogurt, and other alternatives is booming. Whether you are lactose intolerant, allergic to cow’s milk protein, or simply want to cut out dairy for health reasons, the animals or the environment, there’s never been a better time to go dairy-free.

Going vegan has never been easier, there are vegan foods labeled as such in every major supermarket. Find out how easy it is on Viva!’s website here

What is the difference between lactose intolerance and milk allergy?

Lactose intolerance and milk allergy differ in two important ways: (1) by the component of milk that people react to, and (2) by the cause of the reaction. These differences have implications for whether a person can consume any dairy at all, as well as what types of dairy may trigger a reaction.

Lactose intolerance is a reaction to the natural form of sugar present in milk and dairy products, called lactose. Milk allergy is a reaction to one or more of the proteins present in milk, namely whey and casein. People with a milk allergy must therefore avoid all dairy products, because even trace amounts of milk protein can trigger a reaction. People with lactose intolerance need only to minimize their intake of natural milk sugar (lactose), which they can do by: choosing naturally low lactose foods like aged cheese; choosing dairy foods with added lactase enzymes like Green Valley Creamery lactose free products; or taking a lactase enzyme supplement pill with their first bite of a higher lactose foods, such as ricotta cheese or ice cream.

Lactose intolerance is caused by a deficiency in the enzyme responsible for breaking down lactose into simpler sugars, called lactase. It results in unpleasant digestive reactions after consuming dairy, including diarrhea, bloating and flatulence, but this reaction is not harmful to one’s health. Lactose intolerance is a common condition, affecting 60-70% of the world’s adult population.

Milk allergy is caused by an immune system reaction to the proteins found in milk, which triggers potentially life-threatening system-wide symptoms like hives, swelling and anaphylaxis. Some people may also experience gastrointestinal symptoms like vomiting and diarrhea. Milk allergy is far less common than lactose intolerance: Only 2.5% of young children have milk allergy, and most of them outgrow it; less than 1% of American adults are allergic to milk.

Can infants have lactose intolerance or a milk allergy?

CMA is more commonly seen in infants, though it is possible to develop at any age. A milk allergy is one of the most commonly found allergies in infants and young children. About 80% of milk allergies disappear by the time the child reaches the age of five.

Lactose intolerance is not commonly found in infants, though it is possible. Children can also develop a temporary lactose intolerance after a bout of diarrhea or an infection. In these cases, the lactose intolerance usually clears up in a couple of weeks.

Lactose intolerance versus a milk allergy: breastfeeding

It’s important to note that when we talk about milk allergies, we’re usually talking about cow’s milk. It’s rare for babies to be allergic or have an intolerance to breast milk. It is possible for babies to be allergic to something the mother ate that made its way into the breast milk, though. If your baby has a stuffy nose, watery eyes, and/or loose stools, your doctor can help you determine the cause.

Breast milk allergy in babies: With the exception of very rare genetic disorders, babies are not allergic to breast milk. However, it is possible for your baby to be allergic to food or medicine that you took that turns up in breast milk. The usual suspects are dairy, peanut, and soy products. In the case of dairy products, babies might be allergic to whey or casein, two types of protein found in cow’s milk. If you’ve consumed cow’s milk and your baby has CMA, they will get watery eyes, colic, a stuffy nose, and/or diarrhea after breastfeeding. You can solve the problem and resolve any milk allergy symptoms by avoiding dairy products.

Lactose intolerance to breast milk in babies: Lactose intolerance is the inability to digest lactose, a naturally occurring sugar found in milk. Primary, or “true,” lactose intolerance in babies is extremely rare and could be the result of an underlying genetic disorder. True lactose intolerance in babies is a serious condition and requires immediate medical intervention.

Babies can develop secondary, or temporary, lactose intolerance as a result of damaged intestinal lining or a bowel infection. In these cases, the lactose intolerance will disappear once the infection clears up. Unless your doctor tells you otherwise, you can usually continue breastfeeding. If your baby has a condition that requires special care, your doctor will recommend a diet to keep them healthy and happy.

Despite having some similar symptoms, a milk allergy and lactose intolerance are two very different conditions. A milk allergy is an abnormal immune response to proteins found in cow’s milk (sometimes goat or soy milk). Lactose intolerance happens when there’s not enough lactase to break down lactose, a naturally found sugar in milk. A milk allergy can cause rapid and severe symptoms such as shortness of breath and tongue swelling, requiring immediate medical help.

CMA is most commonly found in babies, while lactose intolerance typically appears in adolescents and adults. If your baby is showing an abnormal reaction to milk — watery eyes, stuffy nose, and diarrhea — something in your diet (food or medicine taken while breastfeeding) might be causing it. Your doctor can help you find out whether it’s a milk allergy or lactose intolerance, and the appropriate treatment needed. Read our handy guide on the most frequently asked questions on newborns for more information about your baby’s habits, needs, and more.

Know the Difference: Lactose Sensitivity vs. Lactose Intolerance

By Jaime Hollander

People often refer to lactose intolerance as lactose sensitivity, but medical professionals do not. Lactose sensitivity, or sensitivity due to lactose, can be caused by various conditions. Lactose intolerance is the condition of not being able to digest lactose, the sugar found in milk and dairy products. Nearly 65 percent of the global population has a reduced ability to digest lactose.

Here’s what you should know about lactose intolerance.

What is lactose intolerance? Lactose intolerance is the condition of having a lactase enzyme deficiency. Lactase breaks down the sugar known as lactose, which is found primarily in milk and dairy products. People with lactose intolerance may experience gas, bloating or diarrhea after eating or drinking milk or dairy products with lactose.

Why do people lack the lactase enzyme? After infancy, humans naturally begin producing less lactase. The level of intolerance is what informs the amount of lactose a person can consume before experiencing painful side effects.

What are the symptoms of lactose intolerance? Within 30-120 minutes of consuming milk or milk products, people typically experience a range of physical symptoms, including gas, cramping, bloating, diarrhea and/or nausea.

How bad can it be? Lactose intolerance symptoms can be mild or severe depending on the amount of lactose consumed and the degree of lactase deficiency. Some people who produce small amounts of lactase may be able to tolerate small servings of foods containing lactose. Common signs and symptoms include abdominal pain, gas, diarrhea, and/or bloating.

Dairy allergy vs. lactose intolerance: Are they the same? No – the symptoms of food allergies are different from the symptoms of lactose intolerance. The side effects of lactose intolerance can cause moderate to severe discomfort, but an allergy is far more serious. A true food allergy is a reaction of the body’s immune system that can be severe or life-threatening. Consult your doctor if you think you may have a food allergy.

Lactose intolerance is a common condition, so it’s important to recognize the key triggers and symptoms, and to understand the non-dairy food options available so you and your family can make smart food choices. If you have lactose intolerance, being aware of what’s in your meals and snacks — and the impact those contents may have on your immediate health — is essential to feeling your best every day. And if you’re lactose intolerant but don’t want to give up some of those favorite foods, these products from the LACTAID® Brand will help you eat what you want, when you want.

Except for content on the LACTAID® Brand website, the links provided are for educational purposes only. No sponsorship or endorsement is implied. Information for this quiz came from the Mayo Clinic and the National Institutes of Health.

©Johnson & Johnson Consumer Inc. 2019


1.1.4 Lactose

Lactose (O-β-d-galactopyranosyl-(1–4)-β-d-glucopyranose) is an abundant natural disaccharide that, interestingly, is only found in mammal’s milk where it is the principal carbohydrate and energy source. Lactose is synthesized in the mammary epithelial cells from the glucose and galactose absorbed from blood. Synthesis is catalyzed by a protein complex called lactase synthase, in which the catalytic component, UDP-galactosyltransferase, catalyzes the transferring of the galactose moiety from UDP-galactose (formed via the Leloir pathway) to glucose, and the noncatalytic component, α-lactalbumin, acts by reducing the Michaelis constant of the transferase by several hundredfold (Lehninger, 1975), thus giving glucose a definite advantage over other acceptors to be transgalactosylated.

Lactose exists in the form of two anomers, α and β, differing in the configuration of the substituent groups (OH and H) on carbon atom 1 of the glucose moiety. Both anomers differ in their properties, with their solubility in water being the most important: β anomer is about sevenfold more soluble than α anomer at 20°C (500 vs. 70 g/L), but the solubility of the latter is highly temperature dependent, so that at 93.5°C it becomes more soluble than the β anomer (Fox, 2009). Upon dissolution, mutarotation occurs producing a solution at equilibrium with 63% in the β form. The α anomer crystallizes as monohydrate, while β crystallizes in anhydrous form. Therefore when lactose is dried, a mixture of α-lactose, β-lactose, and α-lactose monohydrate is formed, the proportion of them varying according to the conditions of drying (Zadow, 1984). Alpha lactose is highly hygroscopic, while the other forms are not, so caking and lumping in dairy products is due to the former, which needs to be crystallized prior to drying if a nonhygroscopic product is to be obtained (Schuck and Dolivet, 2002).

Lactose is barely sweet (about 15% sucrose), less soluble than its monosaccharide components, and less soluble than most sugars. Lactose presents problems of intolerance to a significant part of the world population. It is estimated that about two-thirds of the population suffer from lactose maldigestion and intolerance, but the condition is strongly ethnic and age dependent (Schaafsma, 2008), so that there is a marked geographical distribution, as seen in Fig.1.1 (Heyman, 2006; Latorre et al., 2014), and several strategies have been proposed to deal with this problem (Shaukat et al., 2010).

Figure 1.1. Worldwide distribution of adult lactose intolerance (% of intolerance of the population).

These properties of lactose represent severe constraints for its widespread use, so its removal or breakdown is in many cases desirable, as will be analyzed in the following sections. Notwithstanding, in some cases the low solubility of lactose may be an asset when the purpose is using it as a bulking agent or when excessive sweetness is undesirable, as in the case of low-lactose milk (Kailasapathy, 2008); its replacement for sugar in infant foods has been considered adequate to reduce the sensation of appetite and need for sweet foods, preventing overeating. Lactose is considered significantly less cariogenic than other sugars (Schaafsma, 2008).

The only natural source containing significant amounts of lactose is mammal’s milk, so the raw material for its production is invariably whey or whey permeate. Whey protein is a valuable asset, so currently lactose is produced using whey permeate as starting material. Whey permeate contains between 5% and 6% solids, typical composition on a dry basis being: lactose 85%, ash 10%, and protein 3%. The production of lactose from whey permeate considers the following unit operations (Yang and Silva, 1995):

Concentration: usually done by multiple-effect evaporation; in some cases permeate is preconcentrated by reverse osmosis, and preconcentration together with partial demineralization can be done by nanofiltration (Suárez et al., 2009).

Crystallization: done by cooling from a supersaturated solution; alternatively precipitation by alkaline earth metals (Steffen process) and alcohols have been proposed, but its industrial use is doubtful.

Recovery: lactose crystals are recovered by decantation or centrifugation; mother liquor containing most of the minerals and about 20% of the lactose is disposed, as lactose recovery from it is not attractive if no prior demineralization has been performed.

Drying: lactose crystals containing 5–12% moisture are finally subjected to drying in flash or fluidized-bed dryers.

Purification: depending on its use, further refining may be required. Food-grade lactose does not require polishing operations, but for pharmaceutical-grade lactose, refining is necessary; this involves the redissolution of the lactose crystals, the treatment of the solution with activated carbon to absorb a number of solutes including riboflavin, the removal of traces of residual proteins, and recrystallization.

A schematic representation of lactose production from whey is presented in Fig. 1.2.

Figure 1.2. Schematic diagram of lactose production from whey.

Current applications of lactose are many. In the food industry, lactose is used mostly as an energy source and also when low sweetness in the final food product is required. Lactose is used in the confectionery industry to enhance flavor and color in protein-containing goods and in the bakery industry to promote crust browning. Enrichment of cow’s milk with lactose is also an important use aiming to mimic the lactose content in human milk (Polberger and Lönnerdal, 1993), and significant lactose demand comes from its use in the standardization of milk products (Rattray and Jelen, 1996). More intense and widespread use of lactose as a food ingredient is precluded by the high incidence of lactose intolerance (Perotti et al., 2012).

As noted previously, lactose for pharmaceutical use requires higher purity than for edible purposes. Typical United States Pharmacopeia (USP) standard lactose must contain less than 5 μg/g of heavy metals, microbial counts lower than 100/g for Escherichia coli, yeast, and molds, absence of pathogenic bacteria, less than 0.1% residue upon ignition, less than 0.5% weight loss upon drying, and protein and light-absorbing impurities lower than 0.25 absorbance units at 210–220 nm and 0.07 at 270–300 nm (Paterson, 2009). Main pharmaceutical use of lactose is as an excipient because of its cost effectiveness, availability, bland taste, low sweetness, low hygroscopicity, compatibility with active ingredients and other excipients, high physical and chemical stability, and acceptable water solubility; these properties make it the most adequate excipient for tablets, where it is estimated to cover about 70% of all such formulations. This is of paramount importance since about two-thirds of the products used in the pharmaceutical industry are in the form of particulate solids (Fages et al., 2004). Lactose is mostly used in the form of α-lactose monohydrate. Anhydrous α-lactose is less prone to Maillard reaction but its lower disintegration rate is a major disadvantage. Anhydrous β-lactose, produced by crystallization of lactose above 93°C and roller drying, acquires the form of extremely fine crystals having high dissolution rate and good compactness, as its low moisture is adequate for moisture-sensitive active pharmaceutical ingredients (Gohel and Jogani, 2005). Tablets prepared by direct compression use anhydrous lactose produced by drying (usually drum drying), which is essentially β-lactose crystals with a smaller amount of α-lactose (Riepma et al., 1993). Finely milled α-lactose monohydrate is used as excipient in dry powder inhalers, which are currently being used in the treatment of asthma and in chronic obstructive pulmonary disease (Sham et al., 2004; Atkins, 2005). Lactose has been also tested as carrier in nanoparticles delivered to the lung, where it dissolves in the aqueous environment of the lung epithelium, delivering the active pharmaceutical ingredient.

Control of processing conditions for lactose production, storage, and particle properties are crucial for controlling its behavior as an ingredient in foods and drugs (Huppertz and Gazi, 2015).

No. Allergy is a hypersensitivity of the immune system to some elements in the environment that causes no to little problem to most people. Common food allergies are to peanuts, cow’s milk, eggs, tree nuts, fish, shellfish, soy and wheat. In cow’s milk allergy, the immune system overreacts to one or more proteins contained in cow’s milk such as caseins and whey proteins. Symptoms include hives, swelling, nausea and wheezing and can arise within an hour and even up to 72 hours after drinking cow’s milk.

Lactose intolerance is related to lactose, which is not a protein but a type of sugar naturally found in milk and dairy. It’s the inability to digest lactose that results in bloating, diarrhea, and gas. Lactose is not a milk protein but a sugar and it is not targeted by the immune system.

People suffering from cow’s milk allergies should avoid milk and dairy foods whereas people with lactose intolerance should not avoid milk and dairy foods but rather consume dairy in modest amounts, up to 12g in one intake or up to 24 g, preferably in small amounts across the day, during or at the end of a meal (not at beginning), without symptoms. Lactose intolerants are also recommended to consume different forms of dairy such as yogurt, which facilitates lactose digestion, and some cheeses like aged-cheeses, which contain very low to no lactose.


Crittenden et al. J Am Coll Nutr 2005;24:582S-91S.

Efsa Panel on Dietetic Products N, Allergies. Scientific Opinion on lactose thresholds in lactose intolerance and galactosaemia. EFSA Journal 2010;8:n/a-n/a.

Luyt et al. Clin Exp Allergy 2014;44:642-72.

Misselwitz et al. United European Gastroenterol J 2013;1:151-9.

Suarez et al. N Engl J Med 1995;333:1-4.

Understanding Lactose Intolerance


Lactose intolerance is frequently confused with milk allergy, but the two conditions are not the same. A dairy allergy is an immune response that results in inflammation and tissue damage. Such a response to food can be exhibited in any part of the body, therefore it can cause a wide range of problems.

Lactose intolerance is an enzyme deficiency, not an allergy. Many people are lactose intolerant, but millions more have an immune reaction to dairy. Unfortunately, most people don’t recognize that there is a difference between the two issues.

Lactase Is an Enzyme

First, let’s clear up exactly what lactose intolerance is. Lactose intolerance is a deficiency in the enzyme lactase which leads to an impaired ability to digest lactose, which is milk sugar.

The cells lining the digestive tract produce lactase, however many people don’t produce enough lactase to adequately digest this milk sugar. Therefore, these individuals are intolerant to milk sugar.

Many patients complain of a lactose intolerance because they know that they have a problem with dairy products. They usually think taking a digestive product designed for lactose intolerance will resolve their digestive problems. Sometimes it does, but often it doesn’t. When that is happening it’s because what they are experiencing is really a dairy allergy.

Lactose Intolerance Is a Serious Health Problem

Inability to digest and absorb lactose leads to gas, bloating, diarrhea, and abdominal pain. This can be very problematic, but is also very temporary. It will only last a few hours at most.

Any symptoms that last longer must be due to a dairy allergy. A dairy allergy causes irritation of the lining of the intestines. This irritation in turn leads to a weakened digestive system that exposes you to other potential systemic disorders.

In addition to an inability to absorb needed nutrients, a weakened digestive system is more susceptible to attack by parasites, yeast, and pathogenic bacteria, which worsens the problems in your intestines and also exposes you to chronic disease.

Some people have people a lactose intolerance and a dairy allergy. The inability to digest dairy will be just the tip of the iceberg. They often have other problems that indicate the presence of a dairy allergy.

Lactose Intolerance Is a Common Problem

More than 50 million Americans are lactose intolerant and nearly two-thirds of the world’s adult population has some degree of difficulty with the digestion of milk sugar because of a lactase deficiency:

  • 97-100 percent of African Blacks
  • 90-100 percent of Asians
  • 70-75 percent of North American Blacks
  • 70-80 percent of Mexicans
  • 60-90 percent of Mediterranean Descent
  • 60-80 percent of Jewish Descent
  • 10-12 percent of Middle Europeans
  • 7-15 percent of North American Caucasians
  • 1-5 percent of Northern Europeans

Symptoms of Lactose Intolerance

People with a lactose intolerance typically experience an upset stomach, bloating, gas, cramps, and loose stools. These are also common symptoms of a dairy allergy.

One study has also suggested women with lactose intolerance are more likely to have depression or PMS (premenstrual syndrome).

Lactose intolerance symptoms are almost identical to symptoms of other chronic disorders such as irritable bowel syndrome or celiac disease. Studies show as many as 70 percent of lactose intolerant people don’t link their symptoms to consumption of milk sugar.

It’s possible you may actually have lactose intolerance instead of indigestion or an irritable bowel.

Lactose Intolerance Symptoms Are Similar to Dairy Allergy Symptoms

A dairy allergy, like any food allergy, is capable of triggering a wide array of inflammatory symptoms. Like lactose intolerance, a dairy allergy can cause upset stomach, bloating, gas, and loose stools. But, an allergy can also cause other inflammatory symptoms.

We have seen many, many people with these conditions shocked to find that they were suffering from a dairy allergy. If you have any of these symptoms, be sure to consider that you may have a dairy allergy. Dairy allergies are far more common than most people realize, and they cause far more problems than even most doctors realize. For more information on this topic, visit our page on Dairy Intolerance.

Many people who suffer from a dairy allergy don’t know it, and mistakenly believe they can continue to eat dairy products as long as they take a digestive aid, or they avoid milk but still eat cheese, etc. Unfortunately, most continue to suffer from their milk allergy even though their digestive symptoms have diminished.

Diagnosing A Lactose Intolerance

Self-Test for Lactose Intolerance

A simple self-test for lactose intolerance is to drink at least two 8-ounce glasses of milk on an empty stomach and note any intestinal symptoms that develop in the next four hours. The test should then be repeated using a lactose free milk.

If you get symptoms from the regular milk but not the lactose free milk, then you probably have a lactose intolerance. If symptoms occur with both types of milk, then you probably are allergic to dairy products.

However, this self-test is not conclusive because you may unknowingly be consuming lactose. Lactose is “hidden” in hundreds of food products and medications.

The Breath Hydrogen Test for Lactose Intolerance

The more conclusive way to find out if you are lactose intolerant is to get a breath hydrogen test which is available through places like our clinic.

This test is simple to do and is the gold standard for detecting lactose intolerance.

With the breath hydrogen test, you fast overnight, eat a dose of lactose in the morning, and collect breath samples at timed intervals.

If the lactose isn’t broken down by the lactase enzyme in the small intestine, it travels to the colon and undergoes bacterial fermentation. Due to fermentation, hydrogen levels in your breath will rise within 1-2 hours.

Main Ways to Treat Lactose Intolerance

Lactose Avoidance

The most effective treatment is to avoid foods and medications that contain lactose, primarily milk and milk products. Milk, ice cream and yogurt contain quite a bit of lactose. However, fermented dairy products that contain lactose, such as yogurt and kefir, are more easily digested since the bacteria used in the culturing process produces the enzyme that breaks down lactose.

People have differing levels of the lactase enzyme and there are differing levels of lactose in dairy products, so it’s possible you can consume some dairy.

Lactase Enzyme Supplementation

If you do not want to avoid foods with lactose, you can take lactase enzyme supplements to prevent symptoms when consuming lactose-containing dairy products.

Lactase drops may be added to regular milk 24 hours before drinking to reduce lactose levels. Lactase drops, capsules, and tablets may also be taken orally immediately before a meal that has lactose-containing dairy products.

The degree of lactose intolerance varies by individual, so a greater or lesser amount of oral lactase may be needed to eliminate symptoms of lactose intolerance.

In addition, lactose-reduced milk is available in some supermarkets. This will usually be perfectly adequate to solve a lactose intolerance, but will have little or no effect on a dairy allergy.

Many Foods Contain Lactose, Not Just Dairy

Dairy products contain lactose, but not all have the same amount. Cow’s milk has the highest amount of lactose and goat’s milk also contains some lactose.

Other Obvious Sources of Lactose:

  • All cheeses (but some cheeses contain more than others)
  • Butter, many margarines
  • Half-and-half cream
  • Ice cream and sherbets
  • Milk products, including powdered milk, sweetened-condensed milk, or evaporated milk
  • Yogurt

Many foods that most people don’t about as sources of dairy contain lactose because they contain milk products. It’s important to check labels.

Possible Hidden Sources of Lactose:

  • Artificial sweeteners containing lactose
  • Breads, biscuits, crackers, and doughnuts made with milk
  • Breading on fried foods might include dairy
  • Scrambled eggs often contain dairy
  • Breakfast and baby cereals containing milk solids
  • Buttered or creamed foods (soups and vegetables)
  • Cake and pudding mixes
  • Many frostings
  • Candies with milk chocolate
  • Cookies made with milk
  • Hot dogs, lunch meats, sausage, hash, processed and canned meats
  • Salad dressings made with milk
  • Nondairy creamers
  • Pancakes, waffles, toaster tarts
  • Pizza
  • Weight loss products
  • Protein powders
  • Foods containing whey, casein, caseinate, or sodium caseinate

Many prescription drugs including some birth control pills, thyroid medications, and medications for gastrointestinal disorders contain lactose, as do many vitamins supplements.

If you’re avoiding dairy, make sure you’re getting enough calcium. Many foods contain calcium and there is no need to ingest dairy in order to get adequate calcium. But if you aren’t getting enough from your diet, some physicians recommend supplemental calcium. A typical amount of supplemental calcium would be 1,000 mg per day.

If you avoid lactose and your symptoms do not go away, contact us at the IBS Treatment Center. There are many possible causes for your symptoms and we can help sort out why you are suffering and help you get life back.



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