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Lactose Intolerance: Everything You Need to Know

lactose intolerance

Lactose intolerance is a common digestive system disorder. Reliable data indicates that approximately 75 per cent of the world’s population, even if they are not aware of it, suffer from this digestive disorder.

This article discovers the main causes, symptoms, diagnosis and treatments methods of lactose intolerance.

What is Lactose ?

In fact, lactose is a form of sugar found only milk, in turn, products produced from milk. Therefore, sometimes, it is called milk sugar. Galactose and glucose are the two main components of lactose.

Lactose is broken down by an enzyme called lactase secreted in the small intestines. When the small intestine produces none or very little amount of lactase, the enzyme that breaks down the lactose, lactose intolerance occurs.

Lactose is found all dairy products that are produced from milk. Lactose is also found in breast milk, and almost everyone is born with the ability to digest lactose. The occurance rate of lactose intolerance in children under 5 years of age is very low.

What Causes Lactose Intolerance?

As mentioned above lactose intolerance is a common digestive disorder. And, this disease occurs when there is insufficient production of lactase enzyme in the small intestine cells. In general, symptoms start showing themselves between 30 to 120 minutes after consuming milk and dairy products.

The reason that brings about the symptoms- which we will mention about thoroughly in the below- is the lactose passes through the intestines without being broken down into two sugars called galactose and glucose. Insufficient or none lactase production in the small intestine causes this problem.


The types of symptoms and when the symptoms start can vary from person to person. In general, symptoms start in between 30-120 minutes when the person with lactose intolerance consumes any food or drink that contain lactose.

Even though lactose intolerance is not a serious health condition, it can negatively affect the patient’s daily life.

Most common lactose intolerance symptoms


° Farting

• Bloating

° Stomach Growling

• Abdominal Cramps

° Nausea

Note: The severity of the symptoms show alteration based on how much lactose the patient consumed or how much lactose the patient’s body tolerates.


As mentioned at the beginning of the article, it is estimated that one-third of the world’s population have this digestive disorder. Specifically, it is suggested that 2 in every 10 in the UK. Additionally, 30 to 50 million people are estimated to have lactose intolerance problem in America according to the National Digestive Diseases Information Clearinghouse. 

A trusted source proves that lactose intolerance is most prevalent in Africans and Asians and least in the Europeans. According to the report; 5% to 17 % Europeans are thought to have this digestive problem while this percentage rises to 60 to 80 % in Africans and Asians.

Lactose Intolerance Diagnosis

The diagnosis of lactose intolerance is made primarily by evaluating the symptoms against milk and dairy products. Additional tests may be required by the doctor in addition to symptomatic diagnosis.

Lactose Tolerance Test: The patient is requested to drink a liquid solution, which contains lactose, specifically prepared by the medical staff. Thereafter, a blood sample is taken from the patient to see how much blood sugar is available after lactose consumption. If the glucose (blood sugar ) is lower than it should be, the patient is diagnosed as lactose intolerant. However, this test is not very common.

Hydrogen Breath Test: This method is one of the easiest ways to diagnose lactose intolerance. Just as the previous method, the patient is required to consume a liquid containing lactose. After the consumption, the patient blows-up a plastic bag every 15 minutes for roughly 2 hours. Undigested lactase causes certain gases such as hydrogen owing to bacteria in the large intestine.

The aim of this method is to measure the hydrogen level in the breath. If too much hydrogen is measured in the breath after the lactose consumption, then the presence of lactose intolerance becomes evident.

Stool Acidity Test: This diagnosis method is mostly used for babies and children who may have difficulty in performing the previous test ( blowing up plastic bag ). The aim of this method is to detect lactic acid in the stool.

This lactic acid exists in the stool due to fermentation of unabsorbed lactose in the large intestine. Detecting lactic acid in the stool is an indication of lactose intolerance or other metabolic abnormalities which are quite rare.  

Note: Your Physician may require further tests to evaluates other possibilities.

Lactose Intolerance Treatment

Because lactose intolerance is spreading rapidly in society, it can be called one of the most common ailments of the modern age. Dairy products — according to Wikipedia; the products produced from the milk of mammals — are greatly available in many people’s diet.

Therefore, the symptoms of lactose intolerance can be seen in many individuals. As such, these symptoms such as diarrhoea, bloating decrease the quality of life.

As one would expect, eliminating dairy products from the diet is the only way to live life without experiencing the symptoms in question. However, this practice causes other problems since dairy products contain many vital nutrients namely; Vitamin D / A, Phosphorus, Potassium, Calcium, Protein and so forth

Removing all these milk and dairy products from the diet, thus removing mentioned vitamins and minerals can lead to nutritional disorders. Therefore, the changes in the diet should be made under the supervision of a doctor or a registered dietician.