As a child, you guzzled litres of milk, but now, a number of years later, you start noticing that dairy doesn't always agree with you.
For some, however, it's a lot more than a vague, unpleasant feeling and many people experience symptoms like bloating, stomach cramping and diarrhoea – all signs of lactose intolerance.
This is probably the sum total of your knowledge about lactose intolerance. But, to increase your awareness of the problem, here are seven things you may not know about this common digestive ailment:
1. You could be heading towards lactose intolerance
If you love ice-cream, the following news might be upsetting: Research shows that about 75% of the world's population lose the ability to break down lactose at some point, which means that many people naturally become lactose intolerant over time. The prevalence of lactose intolerance in South Africa is estimated at 11.03%.
2. Some ethnicities are more likely to develop it than others
Lactose intolerance is most prevalent among people of East Asian ancestry, affecting more than 90% of adults in some communities, according to the NIH.
The condition is also common in people who are of Jewish, Arab, West African, Greek and Italian descent. On the other hand, people with ancestors from Northern Europe, who consume mostly unfermented milk, have only a 5% rate of lactose intolerance.
3. Lactose intolerance affects everyone differently
People with lactose intolerance have diverse reactions to consuming the offending dairy products. Tiny amounts of lactose may cause intense symptoms such as abdominal cramps and diarrhoea in some, while other might only experience gas.
It's not entirely clear why symptoms vary so much from person to person – it might, however, have something to do with individuals' gut bacteria.
4. Certain types of cheese and yogurt may not trigger the disorder
In many cases, being lactose intolerant doesn't mean you have to say goodbye to the goodness that is dairy. While some people cannot digest much of it, others have no trouble digesting yoghurt, which contains fermented milk, or cheeses such as Parmesan or cheddar. Those cheeses are aged and contain only trace amounts of lactose, making it easier to digest for those with an intolerance.
Here is an easy way to tell which cheeses have low lactose levels: Check the nutrition label. Since lactose is the sugar found in milk, the fewer grams of sugar on the label, the higher your chances of being to digest the product.
5. The symptoms waste no time
The symptoms of lactose intolerance usually occur within 30 minutes to two hours after consuming milk-based products. The more milk products you ingest, the worse you will feel.
6. Babies can be lactose intolerant
There have been cases of babies being born lactose intolerant. This happens when the baby has a mutation of the LCT gene, which normally delivers instructions for making that key enzyme. This results in the baby's small intestine producing little to no lactase, making dairy "complicated". According to the National Institute of Diabetes and Digestive and Kidney Disease, children can inherit genes that cause congenital lactose intolerance from their parents. However, it's extremely rare for babies to have this condition.
7. You might be able to build up your tolerance
While it does sound like an unpleasant experiment for anyone with lactose intolerance, studies argue that consuming small amounts of milk on a full stomach two to three times a day can help to recondition your digestive system to break down dairy without discomfort.
However, if your small intestine does not make enough lactase, it will not suddenly start to do so. You should experiment and find out what works best for you instead of cutting dairy out completely.
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