Cutting lactose out of your diet: who can it help and in what way?

What is lactose intolerance? 

Lactose is the main sugar in dairy products, found only in milk and milk derivatives. To be properly digested, lactose needs a special enzyme called lactase, which is normally produced by the small intestine. This enzyme is responsible for breaking down lactose into two other sugars - glucose and galactose - which can be easily absorbed by the intestine.

In some people, lactase is produced in insufficient quantities. In this case, lactose is not completely digested and reaches the colon, where it is fermented by bacteria.

This process leads to the production of gas in the large intestine and extra fluid in the small intestine, which in its turn accelerates the intestinal transit, causing diarrhea, gas, bloating and abdominal pain.

Who can suffer with lactose intolerance? 

It is very rare for an infant to suffer from lactase deficiency, unless they have a rare condition called congenital lactase deficiency. The activity of lactase tends to decrease progressively when the mother stops breastfeeding the baby. This occurs in extremely variable proportions depending on the individual.

Some adults retain the enzyme in the proportions close to those of infants, while others have lactase levels that fall significantly with age.

There are therefore various degrees of lactose intolerance, depending on the amount of lactase that can be produced by the person. Nevertheless, tolerance threshold is high enough so that a reasonable consumption of dairy products does not cause digestive symptoms.

Lactose intolerance may be temporary, when it develops due to a health condition, such as an intestinal infection, which damages the lining of the small intestine. After recovery, these people are once again able to digest lactose properly. Lactose intolerance can also be long-lasting when it is due to a chronic illness such as coeliac disease or Crohn's disease, for example.

Lactose intolerance should not be confused with irritable bowel syndrome (IBS), which has similar symptoms.

It is important to know that milk allergy is different from lactose intolerance. People with a milk allergy can digest cow's milk normally, but the proteins in cow's milk trigger an immune system response.

What foods can cause the symptoms of lactose intolerance? 

The intensity of the symptoms associated with lactose intolerance varies from person to person. They also vary according to the amount of lactose contained in the food.

Source: Leah Roethel, RD: eat well for life

The symptoms of lactose intolerance generally appear between 30 minutes and 2 hours after ingesting food containing lactose. The more liquid the dairy product is and the faster you drink it, the more severe the symptoms.

Lactose intolerance can be well-controlled by adopting a dairy-free diet.

Note that yogurt is often better tolerated because it naturally contains lactase produced by lactobacilli. Similarly, cheese, which contains less lactose than milk, is often well-tolerated, but this also depends on the quantity of cheese you consume.

Lactose-reduced or lactose-free dairy products are available in many supermarkets.

Should you supplement if you are on a lactose-free diet? 

If you think you're lactose intolerant, it is still recommended not to cut dairy products completely out of your diet, as they are our main source of calcium.

For example, you can turn to lactose-free dairy products and hard cheeses, such as parmesan or cheddar, which contain only traces of lactose: this allows you to have a high-quality calcium intake.

You can also opt for calcium-rich mineral waters, which are a good complement to dairy products.

In addition, to help with lactose digestion, you can follow some of these tips:

• Don't drink too much cow's milk on an empty stomach,
  
• Split your intake of dairy products and eat other foods at the same time,
  
• Incorporate milk into culinary preparations such as mashed potatoes, rice pudding, etc,
  
• Choose yogurts and mature cheeses that contain less lactose thanks to bacteria naturally present in these products, and to the process of cheese draining,
  
• Opt for lactose-free milk rather than plant-based milks, which are often very low in calcium,
  
• Finally, if lactose intake is difficult to monitor and control, for example when eating out, you can use lactase preparations.
  

Calcium contributes firstly to growth and secondly to strong bones. It is important to have an optimal calcium intake throughout the whole life.

If there is a risk of deficiency, talk to your doctor, who can prescribe calcium and vitamin D supplements if necessary.