Just downed a pint of ice cream only to find yourself keeled over, clutching your stomach?

By adulthood, up to 70 percent of people don’t produce enough lactase to properly digest the lactose in milk.

Here’s what to expect.

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Lactose intolerance refers to your body’s inability to break down a natural sugar called lactose, found in your fave dairy products. When your small intestine stops making enough of the enzyme lactase, which breaks down lactose, you’ve got a prob on your hands — and in your gut.

When this happens, the undigested lactose travels to your large intestine, where it can cause the following symptoms:

Lactose intolerance is especially common in adults with Asian, African, and Hispanic ancestry. But even though you’re in good company, that doesn’t make your digestive probs any easier to stomach!

If you took an ill-advised ride on the dairy train, buckle up. Here’s what to know about the gut-churning road ahead.

Most of the time, symptoms of lactose intolerance can happen about 30 minutes to 2 hours after eating dairy and will go away when it completely passes through your system.

Though lactose intolerance can be stressful, the experts from Harvard Health Publishing say it’s not a dangerous condition. But when you feel like a dairy demon crawled in your gut, understandably, it might feel otherwise.

The severity of your symptoms might vary based on how much dairy you downed and the amount of lactase your bod produces.Hold tight, though: According to a research review, unpleasant effects typically fizzle out within 48 hours max unless you keep eating lactose-containing products.

In the meantime, you might experience any of the following symptoms:

  • Bloating. Nothing like eating a few slices of extra cheesy pizza… until the bloat comes on, that is. Bloating happens due to trapped water and gas in your intestines. You’ll usually feel it around your belly button.
  • Nausea. If you have lactose intolerance, nausea often happens within 2 hours of nomming on some yogurt, cheese, or ice cream.
  • Diarrhea. Like the “Bob’s Burgers” song goes, “some people think it’s funny, but it’s really wet and runny: diarrhea.” Yep, pretty much. Diarrhea happens when undigested lactose ferments (yeah, like how pickles ferment) in your gut, causing increased water retention.
  • Pain. Lactose intolerance is seriously a pain in the butt… and gut. When trapped gas pushes against your intestinal walls, it can lead to aches and pains.
  • Gas. You don’t want to be on a crowded subway when lactose intolerance strikes. Fermenting lactose often causes a buildup of hydrogen, methane and carbon dioxide in your gut: One chemical reaction no one wants to witness.

Your tummy probs just might point to something other than lactose intolerance. Food allergies, food intolerances, and other digestive conditions can likewise wreak havoc on your digestive system.

For instance, according to the Office of Women’s Health, lactose intolerance causes similar symptoms to irritable bowel syndrome (IBS) including stomach pain, cramps and diarrhea. However, lots of foods can trigger IBS, while dairy is the sole culprit of lactose intolerance.

According to the FDA, lactose intolerance is also not to be confused with the (much less common) milk allergy, which causes more serious symptoms like:

  • shortness of breath
  • throat swelling
  • mouth tingling

So, what’s the difference? Basically, a food allergy refers to an immune system reaction that can cause serious symptoms throughout your body like, hives, itching, facial and throat swelling (think peanuts and shellfish). It can even be life threatening.

Meanwhile, food intolerances, such as lactose intolerance, stem from your body’s inability to break down a particular food (see: gluten) and usually only impact your digestive system. Here’s how long you can expect symptoms from a few of the most common ones to last:

  • IBS. IBS symptoms can last for days or even months.
  • Dairy intolerance. Dairy intolerance symptoms usually happen within 2 hours of consumption and can last for up to 72 hours.
  • Gluten intolerance. Gluten intolerance typically flares up shortly after eating gluten (like, a matter of minutes) and can last for days.
  • Celiac disease. Celiac disease is a more serious form of gluten intolerance. When people with this autoimmune condition eat gluten, it causes damage to your small intestine. Symptoms usually emerge within minutes to up to 2 hours of consumption. They should subside within a few days.
  • Alcohol intolerance. Those with alcohol intolerance typically notice probs within 20 minutes of having a cocktail, beer or glass of wine. Symptoms will last until the alcohol passes through your system, or around 12 to 48 hours after drinking.

Once lactose intolerant, always lactose intolerant. That’s because the condition is caused by a deficiency of the enzyme lactase, and at least right now, doctors and scientists don’t know a way to increase your body’s production of this enzyme.

You might not be totally SOL, though — there are over-the-counter (OTC) lactase tablets that you can take about 30 minutes before eating a meal containing dairy to mitigate symptoms. However, they don’t work for everybody.

So, unfortunately, it might be time to kiss your lasagna and dairy ice cream goodbye for good. On the bright side, we’ve fully entered the era of the milk alternatives, so there are tons of options to choose from. (Pro tip: if you haven’t tried oat milk, you gotta.)

Lactose intolerance sucks, truly. I mean, who wants to forego cream cheese bagels? But thankfully, it’s not usually a serious condition. Most of the time, you can deal with the concern on your own by cutting out dairy. (OK and I guess there are some other legit bagel toppings out there.)

But if you’re not sure lactose is the culprit, then you may want to chat with a doctor to rule out other digestive conditions. A healthcare provider can check your diagnosis in one of three ways:

Lactose tolerance test

During a lactose tolerance test, your doc will take a blood sample and check your fasting glucose levels. Then, you’ll drink a lactose liquid. Over the next few hours, the doc will compare your blood glucose levels to your baseline.

If your glucose levels didn’t climb, it means your bod can’t break down the lactose into individual sugars. In that case: Yep, you’re lactose intolerant.

Hydrogen breath test

During a hydrogen breath test, you’ll down some liquid with a high concentration of lactose. The doc will then measure the level of hydrogen in your breath.

If you’re lactose intolerant, the fermented lactose will heighten hydrogen levels in your breath, but it can also indicate other conditions as well. Your medical provider can help you interpret the results based on your symptoms and experience.

Stool acidity test

The stool acidity test is usually reserved for children who can’t be tested with other methods. The doctor will examine a stool sample to test for undigested lactose, which appears in the form of lactic acid.

A lactose-limited life isn’t easy, but it’s definitely better than spending every other day stuck on the toilet or wanting to vom. Live your best (low dairy) life by trying the following tips:

  • Eat smaller portions. Depending on the severity of your condition, you may actually be able to stomach a small amount of dairy. Try just a smidge of Parm in your spaghetti or milk in your coffee to see how your bod reacts. You may just have to limit your portions rather than kiss dairy goodbye for good.
  • Take lactase enzyme tablets. If there’s a lactose-laden meal you feel you really can’t miss (hello, gourmet mac n’ cheese), try taking a lactase enzyme tablet beforehand. Word of warning, though: They don’t work for everyone, and you prob shouldn’t pop them nonstop, anyway.
  • Consume probiotics. Pickles, kimchi, kombucha, oh my! According to a research review, loading up on probiotics may reduce lactose intolerance symptoms. In addition to noshing on probiotic-rich foods, you may also want to try a supplement to see if your gut health improves.
  • Cut out the worst offenders. Those 3-cheese enchiladas might not be doing your gut any favors, but hard cheeses, butter, and yogurt might be a little easier on your tum. Since these foods are naturally lower in lactose than other types of dairy, your body might be able to manage them better.
  • Try lactose-free alternatives. You can thank all the vegan and dairy-free folks out there for ramping up the lactose-free alternatives RN. Whether you hit up TJ’s or your local restaurant, there are plenty of dairy-free milks, cheeses, yogurts, ice creams and meals to choose from. As an added bonus, many substitutes are healthier, anyway.