Lactose intolerance: What are the usual causes?

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Lactose intolerance involves inability to breakdown lactose. It is important to note that lactose is typically present in dairy products such as yogurt and milk.

An individual becomes intolerant if the small intestines ceases to produce enough of the enzyme lactase to digest and break down lactose. Once this occurs, the undigested lactose moves into the large intestine. The bacteria normally present in the large intestine interact with the undigested lactose and trigger symptoms such as gas, bloating and diarrhea.

What are the types of lactose intolerance?

  • Primary – this is due to the normal aging process and the most common type. The amount of lactase an individual produce drops over time. The reason for this is that as one starts to age, a diverse diet is eaten and rely less on milk.
  • Secondary – this type is due to an injury or illness such as celiac disease, inflammatory bowel disease and surgery or injury to the small intestines. The level of lactase might be restored if the underlying condition is treated.
  • Congenital – in rare instances, lactose intolerance might be inherited. A defective gene is passed by the parents to their child, resulting to absence of lactase.
  • Development – this type occurs if a child is prematurely born. The reason for this is that the production of lactase in the child starts later in pregnancy after at least 34 weeks.

What are the indications?

The indications of lactose intolerance usually arise between 30 minutes to 2 hours after consumption of milk or dairy products and might include:

  • Bloating
  • Abdominal cramping
    The indications of lactose intolerance usually arise between 30 minutes to 2 hours after consumption of milk or dairy products.
  • Gas
  • Nausea
  • Diarrhea

The symptoms can range from minor to severe. It is important to note that the severity is based on the amount of lactose consumed and the amount of lactase the individual has produced.


At the present, there is no way to urge to body to produce more lactose. The treatment involves reducing or eliminating milk products from the diet.

Individuals who are lactose intolerant can have ½ cup of milk without triggering any symptoms. The products that are free from lactose are available in the market. Remember that not all dairy products include a large amount of lactose.

The individual can still eat some hard cheeses such as Swiss, cheddar and parmesan as well as cultured milk products such as yogurt. In addition, non-fat or low-fat milk usually contain less lactose.

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