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lactose intolerance in adults

What are the symptoms of lactose intolerance in adults?

Lactose intolerance is a medical condition that affects an individual’s ability to digest lactose, a carbohydrate found in dairy products.

According to recent statistics, more than 75% of the world’s population may be experiencing lactose intolerance to some extent, with adults being more susceptible to the condition. 

By birth, all babies are born with the ability to digest lactose, as lactose is found in breast milk. They may develop intolerance towards the substance as they get older, which might explain the prevalence of lactose intolerance symptoms in adults.

Possessing knowledge about the causes of lactose intolerance symptoms in adults and treatment may help you manage this condition more effectively.

Causes of lactose intolerance in adults 

Lactose is a disaccharide, meaning it consists of two simple sugars: glucose and galactose. Your body needs the enzyme lactase to break down these sugars in lactose and digest them. 

Individuals with lactose intolerance do not produce enough lactase, which may be the primary cause of their intolerance towards lactose. The condition can be classified into two different types based on what causes inadequate lactase production.

Primary intolerance

Primary intolerance may be caused by a decline in lactase production due to aging. This type of intolerance may also be partially caused by genes, which might explain why certain populations are more susceptible than others.

According to research, only 5%-17% of Europeans may be affected by the condition compared to 60%-80% of Africans and Asians and around 44% of Americans.

Even in Australia, up to 75% of non-Caucasians may have an intolerance to lactose compared to only 5% of Caucasians.

Secondary intolerance

Secondary intolerance is rarer compared to primary intolerance and may be caused by illnesses such as stomach bugs or coeliac disease, which may lead to inflammation in the gut wall that reduces the production of lactase.


You may experience the following symptoms if you have an intolerance towards lactose:

  • Bloating 
  • Gas
  • Diarrhoea
  • Abdominal cramps

The severity of symptoms may vary from individual to individual based on how much lactose you can tolerate and the amount of lactose you have consumed.

That said, you may not show any symptoms if you consume small amounts of lactose, as most people can handle this quantity without any health effects. According to scientists, most patients with this condition can tolerate up to 18 grams of lactose per day.

Food that contains lactose

All dairy products contain lactose, but the amount may vary depending on which products you consume. Butter and cheese, for example, contain less than a gram of lactose per serving.

Here is a list of non-dairy food products that may contain this carbohydrate:

  • Milk chocolate
  • Desserts and custard
  • Processed meat
  • Potato chips and nuts
  • Bread
  • Cakes
  • Instant sauces and soups


Enzyme supplements

Your doctor might prescribe an enzyme supplement tablet, which you can take directly or mix with dairy products to help you digest lactose.

The effectiveness of this treatment, however, varies from individual to individual.

Exposure to lactose

You may be able to increase the amount of lactase your body produces by including lactose in your daily diet. The increased exposure to lactose might help your body adapt and produce more lactase to break down lactose.

While research on this treatment is not substantial, the initial results have been promising.

Prebiotics and probiotics

Both prebiotics and probiotics have been shown to improve the tolerance of lactose in individuals with this condition. You may also be able to improve your tolerance if you consume food that is rich in probiotics and prebiotics like yoghurt and curd.

Identify lactose intolerance symptoms in adults to manage this condition better

Lactose intolerance is a condition that affects more than two-thirds of the world’s population. Today, this condition is more prevalent in adults compared to children.Understanding its causes, symptoms and treatment may help you manage your condition more effectively. Be mindful of the facts outlined in this post to manage your intolerance towards lactose and improve your digestive health.