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101 Lactose Intolerance

101 Lactose Intolerance

What's the difference between lactose intolerance and milk allergy? How to separate the symptoms and manage it to have a full life not suffering from dairy? Let's look at this information.

Lactose Intolerance 101

Lactose Intolerance (also called lactase deficiency or hypolactasia) is a very common food intolerance. It's a digestive intolerance against one ingredient of milk, called milk sugar/lactose. Lactose is present in cow’s milk, goat’s milk and sheep’s milk in similar quantities. People who has lactose intolerance become sick after eating particular food that contain milk or milk sugar, because their body cannot properly digest it. With a food intolerance, the body doesn’t react with an immune answer to the food, just its digestive system.

Lactose Intolerance is not the same as milk allergy even if they are confused with each other in most cases. Milk allergy is a more dangerous condition, it may cause severe symptoms such as anaphylatic shock, which won’t happen if somebody has a lactose intolerance. This type of intolerance can be treated sometimes, for example, lactase* tablets are available without a prescription to aid those with severe symptoms and usually, there are a large assortment of lactose-free dairy products at most supermarkets.

*Lactase is the enzyme produced by human body to digest lactose and absorb milk nutrients. Those who have a lactose intolerance don't have enough lactase in their digestive system to work this out. This failure of the digestive system is caused by reduced or absent activity of lactase that prevents the splitting of lactose. Lactose itself is a too big molecule for the digestive system, and lactase is supposed to split it to glucose and galactose, which are easier to absorb. Too much undigested lactose sits in the intestines and causes diarrhea and makes the body produce more gas.

Since the body needs 12 hours to digest food, it may be hard to exactly detect what food made you sick. It’s easier when symptoms occur immediately after consuming food.

Who has more chances of having lactose intolerance/lactase deficiency?

Lactase deficiency may occur for one of three reasons: congenital, secondary or developmental.

  • Congenital causes of lactose intolerance is very rare. This may occur because of a congenital absence (absent from birth) of lactase due to a mutation in the gene that is responsible for producing lactase. The symptoms of this type of lactase deficiency occur shortly after birth.
  • Secondary causes of lactose intolerance is due to diseases that destroy the lining of the small intestine along with the lactase. For example, celiac sprue or chron’s disease. This condition can be temporary, and clears up when the original cause is solved, but it can stay for the rest of one's life, especially in adults.
  • Developmental causes of lactose intolerance is the most common cause of lactase deficiency. It is a decrease in the amount of lactase that occurs after childhood and persists into adulthood, referred to as adult-type hypolactasia. This decrease in lactase is genetically programmed, and the prevalence of this type of lactase deficiency in different ethnic groups is highly variable. Some ethnic and racial populations are more affected than others, including African Americans, Hispanic Americans, American Indians, and Asian Americans. The condition is least common among Americans of northern European descent. Lactose intolerance is most common among Asians, affecting more than 90% of adults in some communities. In addition to variability in the prevalence of lactase deficiency, there also is variability in the age at which symptoms of lactose intolerance appear.

Infants born prematurely are more likely to have lactase deficiency because an infant's lactase levels do not increase until the third trimester of pregnancy. Babies likely get sensitive to lactose when they get a disease like stomach flu, and their body cannot produce enough lactase. When this happens, they must get a milk-free (even breast-milk free) diet until the time the illness is gone, and then they can get back milk usually.

For being truth, almost everybody can have a temporary lactose intolerance if they consume more dairy products than they body can digest well.

For detecting the difference between allergy and intolerance, you need to catch the symptoms and their time of reaction. This table might help you to differentiate the two condition, but the best is to see a doctor to be sure that it’s not milk allergy:

Dairy allergyDairy Hypersensitivity
Reaction Time Immediate (within 45 minutes) Intermediate (45 min to 20 hrs)
Trigger Trace amounts of protein Moderate to large amounts of protein
Symptoms Hives, swelling, rashes, coughing, wheezing, shock Gastrointestinal - vomiting, diarrhea, colic
Skin-prick test Positive Negative
IgE levels Elevated Normal
Develops primarily in: Breast-fed babies Formula-fed babies
Later effects Persists for several years; possibly into adulthood Goes away after infancy

Medically this condition can be diagnosed by eliminating lactose from the diet, milk challenge, breath test, blood glucose test, stool acidity test, and intestinal biopsy.

Symptoms of lactose intolerance are primarily gastrointestinal-related, including

  • bloating,
  • stomach aches,
  • diarrhea, gas
  • nausea
  • gurgling or rumbling sounds from belly.

Living with lactose intolerance, treatments

People with lactose intolerance can almost have a normal life. This condition doesn’t need a very strict diet and elimination of all dairy and possibly milk-containing food from our life. In fact, there is typically a dose-related response, that one may be able to tolerate milk in tea, but a glass of milk would cause symptoms. Almost everyone with this intolerance is able to consume a glass of milk without suffering any bad results. They usually can have a variety of milk products, including buttermilk, cheeses, fermented milk products (such as yogurt especially those that contain living, active culture), ice cream, and lactose-free milk, especially if they take lactase pills.

Since lactose intolerance is normally treated with dietary changes, there are dangers from avoidance of milk and milk-containing products such as dietary deficiency of calcium and vitamin D that, in turn, can lead to bone disease (osteoporosis). Although this condition is not as serious as milk allergy, planning a well-balanced diet is essential.

Products that may contain milk and milk sugar:

  • bread and other baked goods
  • waffles, pancakes, biscuits, cookies, and mixtures to make them
  • processed breakfast foods such as doughnuts, frozen waffles and pancakes, toaster pastries, and sweet rolls
  • processed breakfast cereals
  • instant potatoes, soups, and breakfast drinks
  • potato chips, corn chips, and other processed snacks
  • processed meats, such as bacon, sausage, hot dogs, and lunch meats
  • margarine
  • salad dressings
  • liquid and powdered milk-based meal replacements
  • protein powders and bars
  • candies
  • non-dairy liquid and powdered coffee creamers
  • non-dairy whipped toppings

Code-words on the labels that are useful, and mean that the product contains milk:

  • milk
  • lactose
  • whey
  • curds
  • milk by-products
  • dry milk solids
  • non-fat dry milk powder

Hidden and surprisingly lactose-containing products:

  • some prescription medicines, including birth control pills
  • over-the-counter medicines like ones intended for treating stomach acid and gas


Copyright: Zsófia Michelin-Corporatum Oy, Content pictures copyrigh: Shutterstock, Development: e-Com