10 common signs of lactose sensitivity

About 30 to 50 million people have a sensitivity to lactose. Shutterstock

It’s estimated that between 30 and 50 million Americans have some level of sensitivity to lactose, which is a sugar found in dairy products.

A lactose sensitivity can cause all kinds of unpleasant side effects if you consume dairy. Some of them are extremely noticeable, while others might be harder to spot.

Here are a few signs and symptoms of a lactose sensitivity to watch out for.

First of all, a lactose allergy isn’t the same thing as a lactose intolerance.

An allergy is potentially life-threatening — a intolerance or sensitivity is not. S_E/Shutterstock

According to Medical New Today, food allergies are potentially life-threatening and immediate reactions to certain substances in particular foods. Having a food intolerance or sensitivity means that you have difficulty digesting certain foods or have an unpleasant – but rarely life-threatening – physical reaction to them.

Furthermore, a food intolerance is usually caused by an enzyme deficiency while an allergy involves an immune response.

One common sign of a lactose sensitivity is bloating.

Bloating tied to dairy consumption is most likely a lactose sensitivity. Pop Paul-Catalin/Shutterstock

If you always feel bloated after indulging in dairy, you might have a lactose sensitivity.

According to Self, the sensation of bloating can be caused by an increase of water and gas in the colon, which causes the walls of the gut to stretch.

Interestingly, the amount of bloating experienced isn’t actually related to the amount of lactose consumed. Instead, how bloated you feel usually depends on how sensitive your body is to the sensation of the gut wall stretching.

Stomach rumbling is a subtle symptom of lactose sensitivity.

A gurgling belly can indicate more than just hunger. structuresxx/Shutterstock

That growling gut might be a sign of something awry in your digestive system. Technically known as borborygmi, Tufts University related that a gurgling belly is one frequent symptom of lactose sensitivity.

Of course, a rumbling stomach might have many causes that aren’t related to any food sensitivities, so be sure to check your symptoms with a doctor before eliminating dairy.

Gas is another typical hallmark of lactose intolerance.

The colon can’t absorb lactose which leads to gas. Pixabay

Everyday Health reported that a common sign of lactose sensitivity is flatulence and excessive gas.

The colon can’t absorb lactose, but it does contain microflora that can ferment and break it down. Gases are a byproduct of this fermentation and can build up in the colon and intestine, which can in turn cause gas.

An upset stomach might also signal that diary isn’t your friend.

Your stomach can hurt. Joe Raedle/Getty Images

Always get a stomach ache after polishing off a pizza? Dairy could be to blame.

According to Shape, an upset stomach can occur when your body is unable to process lactose. If you’re generally feeling uneasy after eating dairy, talk to your doctor.

If you find yourself running to the bathroom after consuming dairy, you could have an intolerance.

Loose, watery stools after dairy is a good reason to see a doctor. Jungle Jim’s International Market

Diarrhoea is another common and unpleasant symptom of lactose sensitivity, according to Mayo Clinic.

Make an appointment with your doctor if you notice loose or watery stools within a few hours of eating dairy. Sometimes small amounts of dairy don’t trigger symptoms in some people, so it’s important to take note of how much dairy you have consumed prior to an episode of diarrhoea.

You seem to feel worse after having certain dairy products but not others.

Ice cream, cheese spread and cream are high in lactose. Chloe Raissen/SpoonUniversity

Research has shown that some dairy products contain more concentrated levels of lactose than others. Foods such as cheese spread, cream, and ice cream are high in lactose and tend to trigger symptoms in people with a sensitivity.

However, foods such as yogurt and fermented dairy products seem to be less bothersome to people with an intolerance.

If you suspect you are sensitive to lactose, try to notice if certain foods make you feel worse than others and discuss your observations with your doctor.

Vomiting is a rare but observed symptom of an intolerance.

Vomiting isn’t extremely common but can still be a sign. VGstockstudio/ Shutterstock

If drinking a glass of milk makes you vomit every time, you should definitely check in with your physician.

Medical New Today advised that food intolerance symptoms are typically related to the intestinal tract rather than the stomach, so symptoms like nausea and vomiting aren’t as common as flatulence and diarrhoea. However, vomiting after consuming dairy is a reported symptom and warrants a trip to the doctor’s office.

There is some evidence that constipation might also be caused by a lactose sensitivity.

Constipation is a possible symptom. gmstockstudio/Shutterstock

Though diarrhoea is a much more common sign of lactose sensitivity, constipation has also been reported as a possible symptom.

Experts theorise that the methane gas produced by lactose fermentation in the colon might to increase the time it takes for food to move through the digestive system, leading to constipation. However, more research is needed to determine if constipation is a reliable indicator of lactose sensitivity.

If this is the only symptom you’re experiencing, it’s worth talking to a medical professional to rule out other causes of constipation first.

Feeling generally ill after consuming dairy might be a sign that it’s time to talk to your doctor about lactose sensitivity.

If you associate sickness with dairy, it’s probably time to see a doctor. Simon Kellogg/Flickr

If you notice that you tend to feel generally unwell after a meal containing dairy, it might be a good idea to speak to a medical professional about your symptoms.

According to the National Health Service, a feeling of illness or subtle symptoms such as slight stomach pain or bloating can signal a sensitivity to lactose. Pay attention to your body and take note of any negative sensations that crop up shortly after eating something containing lactose.

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