Could You Be Lactose or Gluten Intolerant?

Food intolerances seem to be increasing among the general population however it's important to understand and differentiate between food allergies and intolerances. 

Unlike true allergies, food intolerances are not life-threatening but they can cause a lot of problems and discomfort. A food allergy triggers an immune system reaction which is not the case with an intolerance. 

An intolerance means you have difficulty digesting a specific food. This can be caused by a lack of specific enzymes, naturally occurring chemicals in foods, food additives, and histamine. When you ingest the problematic food you will usually encounter symptoms within a few hours and up to days later (1). Unlike a food allergy which provokes an immediate reaction, an intolerance can, therefore, be more difficult to pinpoint. 

Food intolerances are said to affect up to 20% of the world's population (2), the most common being fructose, lactose, and gluten. 



What is lactose intolerance?

There are two forms of lactose intolerance: primary and secondary.

Primary lactose intolerance is the most common, as it is caused by a decreased production of the enzyme lactase. This usually develops after the age of 5 when our bodies start to produce less of this enzyme. 

Most of us can digest lactose as children but about 75% of us lose this ability once we reach adulthood (3). Insufficient lactase production results in unabsorbed lactose in the intestines that can ferment and cause digestive problems like gas and bloating.

Lactose intolerance is more common in certain populations such as East Asian, West African, Arab, Jewish, Greek, and Italian which supports the claim that it may be linked to genetics (4)

Secondary lactose intolerance, on the other hand, is a rarer condition.

Secondary lactose intolerance is caused by illness, injury, or surgery within the small intestines. This can look like Celiac or Crohn's disease. These types of circumstances promote inflammation in the mucosal lining which can damage the intestines and inhibit lactase production.


How do you know you have lactose intolerance?

The signs and symptoms of lactose intolerance usually begin 30 minutes to two hours after eating or drinking foods that contain lactose.

These symptoms may look like abdominal cramping, acne, bloating, diarrhea, gas, eczema, vomiting, headaches, nausea. 

An elimination diet is one of the best evaluators for lactose intolerance. This involves the elimination of lactose products for at least 28 days and reintroducing them to assess if any symptoms occur. If you are lactose intolerant, it will be obvious.

Sometimes a doctor will order a hydrogen breath test, blood sugar test, or stool test to confirm the diagnosis (5)

Treatment for lactose intolerance

The number one thing you can do is avoid lactose-containing foods. Lactose is found in milk, yogurt, cream, butter, ice cream, and cheese but it can also be hidden in baked goods, packaged foods, salad dressings, sauces, soups, etc.

You may be able to tolerate lower lactose-containing foods such as aged cheeses, butter, probiotic yogurt, and kefir. 

Consuming plenty of probiotics and prebiotics can also help to alleviate gut symptoms and improve tolerance.



Gluten intolerance

The term gluten intolerance is an umbrella term and may refer to three types of disorders: autoimmune celiac disease, wheat allergy, and non-celiac gluten sensitivity.


Celiac Disease

Celiac disease is an autoimmune condition triggered by genetic and environmental factors and affects about 1% of the worldwide population. With this condition, the intestinal mucosa is damaged by the protein gluten, which can impair nutrient absorption. This can lead to a whole host of problems such as malnutrition and digestive distress. 


  • Diarrhea
  • Fatigue
  • Weight loss
  • Bloating and gas
  • Abdominal pain
  • Nausea and vomiting
  • Constipation

How do you test for Celiac Disease?

You can test for celiac disease with bloodwork testing for TGG antibodies or a small intestinal biopsy. An elimination diet is also a good indicator.

What's the treatment for Celiac Disease?

Those who are diagnosed with celiac disease need to completely and permanently avoid any form of gluten in their diet. 

This can be tricky as gluten may hide in various products so always remember to verify labels! Gluten is found in grains such as wheat, rye, barley, and spelt but it also can hide in various food products like sauces, dressings, soups, and beverages. 

Be sure to check out our guide on going gluten-free here


Non-celiac gluten sensitivity

Non-celiac gluten sensitivity is much more common than celiac, however, it is a fairly new condition in the medical community. 

When a celiac person ingests gluten, his or her immune system will attack its own body’s tissue. Whereas, if a person is gluten sensitive, the consumption of gluten can cause short-term bloating and belly pain but also less obvious and systemic symptoms like brain fog and acne. 

Symptoms typically appear hours or days after gluten has been ingested, a typical response for innate immune conditions like non-celiac gluten sensitivity.


  • Diarrhea
  • Fatigue
  • Bloating
  • Stomach ache
  • Nausea
  • Gas
  • Constipation
  • headache
  • fatigue
  • numbness in legs or arms 
  • joint pain
  • skin conditions
  • brain fog

How do you test for non-celiac gluten sensitivity?

You can test for IgG antibodies against gluten however this is not always accurate which can make NCGS tricky to diagnose (6). The best way to establish if you have a problem with gluten is to remove it for at least 3 weeks and then reintroduce it to verify if symptoms occur. 

What's the treatment for non-celiac gluten sensitivity?

Avoidance of gluten foods is the best way to treat NCGS. 


Wheat allergy

Wheat allergy is different from Celiac disease and NCGS because it results from an abnormal immune response to wheat. This is a true food allergy. What happens is the immune system overreacts to the wheat causing symptoms that are potentially serious or even life-threatening. These symptoms are fairly immediate, occurring minutes to hours after ingestion, and may include hives, shortness of breath, lightheadedness or vomiting. A food allergy is an IgE immune-mediated reaction, not an autoimmune condition (7)


  • Swelling, itching or irritation of the mouth or throat
  • Hives, itchy rash or swelling of the skin
  • Nasal congestion
  • Headache
  • Difficulty breathing
  • Cramps, nausea or vomiting
  • Diarrhea
  • Anaphylaxis

How do you test for a wheat allergy?

An elimination diet or food diary can help you assess whether wheat is an issue for you or not. Your doctor will conduct a skin prick test or a blood test to verify the allergy. 

What's the treatment for a wheat allergy?

The best treatment for a wheat allergy is the avoidance of all wheat products. Make sure you read the label and ask questions when eating out to avoid potential exposure. 

About the Author

Laurence Annez

Laurence Annez
Laurence Annez is a Certified Nutritional Practitioner and Health Coach, specializing in PCOS and women's hormones. She also holds a degree in Creative Writing and has extensive experience writing on health and wellness topics. Laurence's mission is to inspire and motivate individuals to take control of their own health and reach their ultimate health goals.