Information
Below you'll find some information about lactose intolerance. If you have any questions about lactose intolerance after reading this page, please feel free to complete the questionnaire at the bottom of the page.
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Introduction to lactose intolerance
People who are lactose intolerant have trouble digesting the milk sugar found in dairy products. Lactose is found in all dairy products from mammals such as cows and goats, in all dairy products such as cream and cheese, and in products where dairy ingredients have been used in the manufacturing process.
When someone reacts to lactose, it is called malabsorption, but only people who are lactose intolerant experience symptoms. Lactose intolerance occurs when the body does not produce enough of the enzyme lactase in the small intestine, where lactase is supposed to convert lactose into sugars (glucose and galactose). If this does not happen, the remaining lactose ends up in the large intestine where it is fermented by bacteria, causing problems. The most common symptoms people experience with lactose intolerance are: gas, bloating, discomfort, intestinal rumbling, diarrhea, nausea, stomach pain and constipation.
Why can some people have a little lactose and others can't?
The amount of lactose a person can digest depends on how much lactase is naturally produced in the stomach. Some people can digest a certain amount of lactose, while others cannot. Everyone is born with enough lactase to digest breast milk, but as children grow up and start eating other foods, the production of lactase also decreases. Unfortunately, not all people continue to produce enough lactase and develop lactose malabsorption, which can develop into lactose intolerance. Some people with lactose intolerance can still digest some lactose, such as Swiss cheese and dark chocolate, which are naturally low in lactose.
Where is lactose intolerance (malabsorption) most common?
Lactose intolerance is inherited through DNA and the likelihood of having it depends on where your family comes from. Lactose intolerance is most common in people of African, Asian, Hispanic and Middle Eastern descent. In these regions, dairy consumption is lower than in other regions, such as European countries. According to a 2017 study, 73% of the population in Japan has lactose malabsorption, with the highest percentage in Yemen, Ghana, South Korea and Malawi at 100%. The lowest percentage of people with lactose malabsorption is in Northern Europe, with Ireland and Denmark having the lowest prevalence of 4% of the population
Are there different types of lactose intolerance?
Yes, there are actually three main types:
1. Primary lactose intolerance, where there is insufficient production of lactase in the small intestine to convert lactose into sugar. This is the most common type.
2. Secondary lactose intolerance occurs when the bowel is damaged, for example by infection, inflammation, surgery or radiation to the bowel. This type of lactose intolerance can be temporary and when the bowel is repaired it will be able to produce enough lactase again.
3. Congenital lactose intolerance, this is a rarer and inherited form of lactose intolerance. If someone is born with this form, there is very little or no lactase in the body, so even breast milk cannot be digested.
Lactose intolerance and other bowel conditions
The symptoms of lactose intolerance can be similar to other conditions, such as celiac disease (gluten) and irritable bowel syndrome. Symptoms such as diarrhea, gas, bloating and abdominal pain can be common to all three conditions. Studies have shown that lactose intolerance is over-diagnosed and celiac disease under-diagnosed because the symptoms are similar. It can take up to a year for doctors to correctly diagnose someone with celiac disease. If someone has celiac disease, they may have a higher chance of also having lactose intolerance, but as a secondary lactose intolerance. After 1-2 months of gluten avoidance, lactase production should return to normal levels.
Too much lactose?
You'll also find dairy ingredients in medicines and food supplements. Manufacturers add (skimmed) milk powder or other dairy ingredients during food production. This makes it harder to read product labels and be aware of hidden lactose in foods, because a dairy ingredient isn't always listed as such. An example is the use of artificial flavourings or colourings in sweets, sausages, mayonnaise, ready meals, (baby) cereals, musli, shakes and bouillon cubes. Manufacturers add lactose to products such as sweets, waffles and biscuits because it gives them a better taste and colour, it binds better with water and the texture is smoother.
Are we missing out on nutrients because we can't eat dairy?
Eliminating dairy products from your diet can lead to health problems, because the nutrients in dairy products are an important part of a healthy diet. Milk helps the body develop in a number of ways, including strong bones and steady growth in children. Milk is a natural source of protein, calcium, vitamins B2, B12, A and D, phosphorus and potassium. It also helps prevent diseases such as osteoporosis.
One solution for dairy products is to take lactase supplements just before consuming lactose. This can sometimes be tricky as too much lactase can cause constipation and there is a limit to how many supplements you can take each time you consume dairy products.
Overlooked symptoms
Some of the symptoms of lactose intolerance mentioned in the introduction are abdominal pain/discomfort, bloating, rumbling and flatulence. All four of these bowel-related symptoms are the most common when someone is having a reaction to lactose. Some symptoms are less common and can be easily overlooked, such as nausea, vomiting, difficulty concentrating, constipation, low mood, muscle pain, joint pain, swelling and stiffness, tiredness, poor short-term memory, and headache or dizziness. What's more, lactose can be easily overlooked as a possible diagnosis for people experiencing these problems. And because it's not always clear whether a product contains lactose, it can cause distress to someone who is unaware that they are lactose intolerant.
An intolerance or an allergy?
Lactose intolerance is different from a milk allergy. People who are lactose intolerant react to the sugar in milk, whereas with a milk allergy your body reacts to the protein in milk products. A milk allergy is more serious than lactose intolerance because it affects the immune system.
Sources and disclaimer
Disclaimer
*If you experience any form of physical discomfort related to dairy products, please consult a doctor. The information on this website is for informational purposes only.
**All the information above is taken from acknowledged websites and articles and all of that information has been acquared through clinical research.
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