Are you suddenly lactose intolerant? This is why.

On social media discussion websites like Reddit and Quora people are bemoaning the seemingly abrupt development of lactose intolerance. It’s frustrating if, after years of being able to eat dairy, it suddenly feels like these foods are off-limits.

Why does that happen?

Lactose intolerance occurs when your body is unable to digest the sugar lactose, which is found in milk and milk products. This causes uncomfortable symptoms including gas, bloating, cramps and even nausea or vomiting. We talked to experts to discover why this condition may suddenly develop— and how long it will last. 

Why am I suddenly lactose intolerant?

There are a couple of reasons why someone develops lactose intolerance. One is age-related lactose intolerance, known as primary lactose intolerance. Over time, your body produces less of the enzyme lactase. This enzyme breaks down the lactose sugar into two smaller, digestible components. Without it, lactose builds up in your gastrointestinal tract and you experience uncomfortable symptoms.

This type of lactose intolerance is perfectly normal, says Dr. Christopher Schmoyer, an assistant professor of Gastroenterology at the Perelman School of Medicine at the University of Pennsylvania. “Our bodies really are only meant to drink milk and digest it when we’re babies. … So, it’s a normal thing that over time our own body’s ability to make that enzyme just decreases,” he adds. According to Schmoyer, this type of intolerance is fairly common and usually occurs around mid-adulthood.

Secondary lactose intolerance is another kind of intolerance. Secondary lactose intolerance can feel abrupt and occurs because of an issue in your small intestine, where lactase is produced. According to NHS inform, damage can be caused by an infection, antibiotics, cancer treatments or long-term GI conditions like Crohn’s disease.

How do you reverse lactose intolerance?

How long you are lactose intolerant depends on what causes the condition. If you have secondary lactose intolerance, your intolerance may only be temporary. According to the Mayo Clinic, “treatment of the underlying disorder [that led to the intolerance] might restore lactase levels and improve signs and symptoms.” It may take time for this restoration to occur though. NHS inform states that if a long-term illness causes lactose intolerance, however, the condition will likely stay.

If your lactose intolerance is simply a byproduct of getting older, it will likely be a lifelong condition. There is nothing you can do to increase the amount of lactase your body makes. Instead, you can learn to manage your symptoms. You can achieve this by trying different types and amounts of dairy products and seeing which triggers discomfort. Avoiding these products will keep you feeling good. You can also look for lactose-free items and lactase supplements, like Lactaid.

What happens if you ignore your lactose intolerance?

I get it. Excluding your favorite ice cream or cheese from your diet can be so hard. So, what happens if you just, don’t? Fortunately, you won’t cause long-term damage to your GI tract, says Schmoyer. You probably will just feel bad because of the resulting uncomfortable symptoms.

So maybe just try a Lactaid supplement with your ice cream. It probably couldn’t hurt!

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