When lactose becomes a problem

Food intolerances are increasingly common and clinically relevant.

It is estimated that two thirds of the world population suffer from lactose intolerance. In Portugal this problem affects one third of the population. 

What is lactose intolerance?

Lactose intolerance is caused by a deficiency of the enzyme lactase (the body does not produce enough lactase).

Lactose is the sugar in cow's milk.

Lactase is the enzyme that the body produces in order to easily digest the lactose present in dairy products.

When lactase deficiency occurs lactose is not fully digested, causing lactose malabsorption. As a consequence, lactose is not absorbed and reaches the large intestine, where it is fermented by bacteria, causing gas and colic.

Can you tell the difference between lactose intolerance and milk allergy?

Lactose intolerance occurs when the body, more specifically the digestive system, is not able to properly digest lactose due to an enzyme deficiency.

Milk allergy is an immune system response that creates defences to fight the "enemy", known as casein (milk protein). It occurs in early childhood and remains throughout life.

Symptoms of milk allergy include: 

What should you do?

If you suspect you suffer from lactose intolerance, it is recommended to keep a food diary. In that diary you should record everything you eat, as well as the symptoms whenever they appear.

The goal is to establish a causal relationship between food and symptoms.  

Living with lactose intolerance...

For people without a diagnosed intestinal disease, treatment involves changing their diet.

How to prevent the above-mentioned symptoms? 

Which foods contain lactose?

Lactose is a type of sugar which is naturally present in milk of animal origin.  Thus, the foods with the highest lactose content are milk (whole milk, semi-skimmed, skimmed, skimmed, with chocolate), condensed milk, powdered milk, butter, cheeses, yoghurt, cream, and ice cream.

In addition to these, there are other foods that have less milk in their composition and therefore, they can be better tolerated.