Causes of Lactose Intolerance

Lactose intolerance causes an inability to digest sugar due to a deficiency of the enzyme, lactase. What are the factors that can cause this condition?
Causes of Lactose Intolerance

Last update: 09 December, 2020

Lactose intolerance is a growing problem that affects a large number of people. It’s influenced by both genetic and environmental factors. Fortunately, there are some circumstances where this intolerance can be corrected. However, it’s essential to pay attention to the causes of lactose intolerance.

Before we begin, it’s important to underline the fact that intolerance is not the same thing as an allergy. An allergy causes a disproportionate autoimmune response when it comes into contact with an antigen. On the other hand, an intolerance is usually the inability to digest or metabolize a certain nutrient.

Main causes of lactose intolerance

The cause of lactose intolerance can originate from a variety of different factors. One study identified a genetic component and more information on this was published in the journal Gut. This study shows that some people lack the genetic information necessary to develop the enzyme that metabolizes sugar, known as lactase.

However, at other times the cause of this problem could be bacterial. An intestinal dysbiosis, or an alteration of the biodiversity of the gut microbiome, could create the environment for a temporary intolerance to appear.

This bacterial cause was confirmed by a study published in the Critical Reviews in Food Science and Nutrition Journal. Fortunately, these temporary problems respond well to probiotic treatments and can be resolved in a short amount of time.

Similarly, intolerance to lactose can develop during a temporary reduction in consumption. During these time periods where someone consumes less lactose than normal, the human body tends to save it.

In this way, if you completely cut out the intake of lactose for a long enough time, your body will cease to produce lactase. This is because it’ll understand that you no longer need it, and the process requires energy. Therefore, when you reintroduce lactose to your diet, your body won’t be able to digest it correctly.

Cups of milk

Causes of lactose intolerance: lactose isn’t all bad

Despite the fact that some current sources will tell you the opposite, lactose isn’t a harmful nutrient for health. No study has proved it capable of causing a harmful inflamed state in the body, at least in the amounts typically consumed for a daily diet. Because of this, except in situations of a properly diagnosed genetic intolerance, there’s no reason to restrict your intake.

In addition, in the case of lactose intolerances, a good option before completely cutting sugar out of your diet is to experiment with probiotic treatments.

It’s shown that these microorganisms are extremely effective at preventing the onset of symptoms related to this problem. In fact, it’s even been shown that probiotics can reverse the situation by stimulating the production of lactase through the bacteria that live in the gut.

Causes of lactose intolerance and the importance of a diverse diet

One very important thing to keep in mind when it comes time to planning your menu is that your diet needs to be varied and balanced. You shouldn’t restrict food groups from your diet without previous medical advice derived from the existence of a diagnosed illness. If not, the remedy could be worse than the illness.

Chocolate breakfast milk

The ideal thing to do is to include lots of fresh foods in your diet. The only thing you need to try to avoid is ultra-processed foods and toxins such as alcohol. This class of foods doesn’t offer any nutritional benefit for the body. In fact, they’re actually capable of increasing the incidence of chronic and complex diseases.

You don’t need to restrict lactose if you’re not intolerant

Lactose intolerance is a common fact of life for many communities that have restricted intake of dairy for many years. One example is the Chinese population, whose diet has historically included very few dairy products. However, in most Western countries, except in concrete cases of genetic alterations, this nutrient is digested adequately by the body.

Many of the current causes of this lactose intolerance respond to a picture of intestinal dysbiosis. This can be corrected adequately with the use of probiotic supplements. In this way, sugar is digested better and the associated symptoms are reduced.

However, if lactose makes you feel unwell, the most appropriate thing to do is to consult a specialist to diagnose the problem. In the event that you’re diagnosed with an intolerance, try the prescribed treatment. If this doesn’t produce results, your intolerance could be genetic. The best solution, in this case, would be to eliminate lactose from your diet or introduce the enzyme lactase.

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  • Misselwitz B., Butter M., Verbeke K., Fox MR., Update on lactose malabsortion and intolerance pathogenesis, diagnosis and clinical management. Gut, 2019. 68 (11): 2080-2091.
  • Oak SJ., Jha R., The effects of probiotics in lactose intolerance: a systematic review. Crit Rev Food Sci Nutr, 2019. 59 (11): 1675-1683.