What is Lactose Intolerance?
Lactose intolerance is a condition wherein the body has difficulty in digesting lactose, the natural sugar found in milk and other dairy products.
It is different from having a food allergy to milk. When lactose is not properly digested, it causes discomfort when moving through the colon or large intestine.
Some people with lactose intolerance can eat or drink small amounts of dairy products or particular types of dairy products without having problems, but others cannot digest any kind of dairy products even in minimal amounts[1].
A big challenge for people with this condition is learning how to avoid discomfort by choosing food carefully and getting the recommended amount of calcium for healthy bones daily.
Lactose Intolerance Signs And Symptoms
The signs and symptoms of the condition usually start to be experienced within 30 minutes to 2 hours after consuming foods with lactose.
The common signs and symptoms of lactose intolerance are:
- Gas
- Bloating
- Nausea and in some cases vomiting
- Diarrhoea
- Cramping of the abdominal area
In many cases, the symptoms are just mild but they can sometimes be severe depending on the severity of lactose intolerance and how much dairy products were consumed.
If you or your child has any signs and symptoms that are worrisome like severe abdominal pain, consult your physician.

The severity of symptoms may depend on how much lactose you can tolerate. Shutterstock Images
Lactose Intolerance Causes and Risk Factors
The main cause of lactose intolerance is not having enough of the enzyme lactase, which is produced by the cells lining the small intestine.
The factors that make a person more prone to lactose intolerance:
- Aging: The condition becomes more common as a person gets older. It is not very common in babies and very young children.
- Ethnicity: Lactose intolerance is very common in African Americans, Asians, American Indians and Hispanics.
- Premature Birth: Some infants that are born prematurely have lower levels of the enzyme lactase because it increases in the foetus during the late part of the third trimester.
- Diseases That Affect the Small Intestine: Certain problems of the small intestine can lead to lactose intolerance. This includes the overgrowth of bacteria, Crohn’s disease and celiac disease.
- Some Treatments for Cancer: Radiation therapy in the abdominal area or chemotherapy complications can cause lactose intolerance.
Types of Lactose Intolerance
There are three main types of lactose intolerance:
- The first is congenital lactose intolerance wherein the person is born with the condition. This is a rare type of the condition, but some prematurely born babies have lactose intolerance, and in some cases it is hereditary.
- The second is primary lactose intolerance wherein it develops as a person gets older. As the diet becomes more varied becoming less reliant on milk, lactose intolerance may develop[2].
- The third is secondary lactose intolerance wherein injury or illness causes the insufficient production of the enzyme lactase. In most cases, treating the underlying disorder can improve signs and symptoms.
Tests and Diagnosis For Lactose Intolerance

Hydrogen breath test used to determine if abnormal bacteria are present in the colon. Researchgate Images
Physicians may suspect lactose intolerance from the symptoms of the patient and how they respond to the reduction of dairy foods from their diet.
Confirmation of the diagnosis can be done through one or a combination of the following tests:
Treatments and Medications For Lactose Intolerance
In most cases, the best treatment is to limit the amount of dairy product in the diet.
According to WebMD, most people with lactose intolerance can consume about 10 grams of lactose a day, which is the amount in a glass of milk.
Eating or drinking dairy products with other foods can also reduce or even eliminate symptoms in most cases.
Those who are highly intolerant to lactose can take lactase as a supplement whenever they consume dairy products to relieve or prevent the different signs and symptoms.
Precautions and Self Care
If you have lactose intolerance, you need to reduce the intake of dairy products.
This may cause problems involving calcium intake, but there are other food sources for the vital bone-building mineral-like broccoli, calcium-fortified cereals and juices, canned salmon, soy milk and spinach.
You can also take a calcium supplement or multivitamin with enough calcium.
If you want to consume dairy products, try lactase supplements like Lactaid.