21 Common Signs of Gluten Intolerance (2024)

Gluten-related disorders (GRDs) such as celiac disease, non-celiac gluten sensitivity (NCGS), and wheat allergy can affect your skin, digestive system, mood, and joints.

Gluten intolerance is becoming common. It’s characterized by adverse reactions to gluten, a group of proteins found in wheat, barley, and rye.

Several disorders are considered GRDs, including celiac disease, NCGS, and wheat allergy (1).

All three gluten-related disorders may cause widespread symptoms, many of which have nothing to do with digestion.

This article takes a closer look at some of the most common symptoms of gluten intolerance.

Celiac disease is the most severe gluten-related disorder.

It’s an autoimmune disease that affects about 1% of the population and may damage the digestive system (2).

Celiac disease can cause many symptoms, including skin problems, digestive issues, and mood changes. It’s disruptive to daily life without the appropriate diagnosis and management.

Here are a few of the most common symptoms of celiac disease.

1. Diarrhea, constipation, and smelly feces

Individuals with celiac disease experience inflammation in the small intestine after eating gluten.

This damages your gut lining and leads to poor nutrient absorption, resulting in significant digestive discomfort and frequent diarrhea or constipation (3).

Frequent diarrhea can cause major health concerns, such as electrolyte imbalance, dehydration, and fatigue (4).

People with celiac disease may also have pale and foul-smelling feces due to poor nutrient absorption (5).

2. Fatigue

Many people with autoimmune disorders, including celiac disease, often feel tired. Several factors may contribute, including (6):

• chronic pain
• sleep disruptions
• psychological conditions like depression and anxiety
• inflammation

Celiac disease may also be linked to a higher risk of iron deficiency anemia, which affects your ability to produce healthy red blood cells. This can cause several serious side effects, including decreased energy levels and fatigue (7, 8).

3. Skin reactions

Gluten intolerance also affects your skin.

A blistering skin condition called dermatitis herpetiformis is one manifestation of celiac disease (9).

Although everyone with celiac disease is sensitive to gluten, some people only experience skin symptoms without the common digestive symptoms (10, 11).

Several other skin conditions have been shown to improve via a gluten-free diet. These include:

• Psoriasis: Psoriasis is an inflammatory condition characterized by scaling and discoloration of the skin (12, 13).
• Alopecia areata: Alopecia areata is an autoimmune disease that manifests as non-scarring hair loss (14, 15).
• Chronic urticaria: Chronic urticaria is a skin condition characterized by recurrent hives with pale centers (16).

4. Depression and anxiety

In 2020, nearly 1 in 10 Americans reported having depression, with the prevalence as high as 20% among adolescents and young adults. (17).

People with digestive issues may be more prone to both anxiety and depression than those without any underlying conditions (18).

Depression and anxiety are especially common among people with celiac disease (19, 20, 21).

A few theories suggest how gluten intolerance may influence depression. These include:

• Mood disorders: People with celiac disease may be prone to anxiety or depression (22, 23).
• Cerebral hypoperfusion: This is when there is excessive blood flow in the carotid artery, which can be life threatening (23).
• Vitamin deficiency: This can occur because the body cannot properly absorb nutrients, also known as malabsorption or hyperhom*ocysteinemia. (23).
• Gluten exorphins: These peptides are formed during the digestion of certain gluten proteins. They may interfere with the central nervous system, raising your risk of depression (24).
• Changes in your gut microbiome: Increased amounts of harmful bacteria and decreased amounts of beneficial bacteria may affect the central nervous system, increasing your risk of depression (25, 26).

5. Unexplained weight loss

Although it may stem from various factors, unexplained weight loss can be a side effect of undiagnosed celiac disease (27).

That said, unexpected weight change is more common in children with celiac disease, especially those younger than 3 years. That’s because they are more likely to experience severe gastrointestinal symptoms such as loss of appetite, diarrhea, and failure to thrive (28).

While weight loss can occur in adults, it appears rare (29).

6. Iron deficiency anemia

Iron deficiency is the most common nutrient deficiency and accounts for 50% of all anemia cases worldwide (30).

It causes symptoms like (30):

• low blood volume
• fatigue
• shortness of breath
• dizziness
• headaches
• pale skin
• weakness

Celiac disease impairs nutrient absorption, resulting in reduced iron absorption. Iron deficiency anemia may be among the first symptoms of celiac disease a healthcare professional notices (7).

Research suggests iron deficiency may affect children and adults with celiac disease (31, 8).

7. Autoimmune disorders

Celiac disease is an autoimmune disease that causes your immune system to attack your digestive tract after you eat gluten (2).

It also makes you more prone to other autoimmune conditions, such as those affecting the thyroid. These conditions, like Hashimoto’s thyroiditis, can cause anxiety, depression, fatigue, and other symptoms that impact the overall quality of life (32, 33, 34, 35).

Celiac is more common in people with other autoimmune diseases, such as type 1 diabetes, autoimmune liver diseases, and inflammatory bowel disease (IBD) (32).

8. Joint and muscle pain

People experience joint and muscle pain for numerous reasons.

It’s possible that those with celiac disease have a genetically determined oversensitive nervous system, causing a lower threshold to activate sensory neurons that cause pain in muscles and joints (36, 37).

9. Leg or arm numbness

Another surprising symptom of gluten intolerance is neuropathy, which involves numbness or tingling in your arms and legs.

This condition is common in individuals with diabetes and vitamin B12 deficiency. It can also be caused by celiac disease, exposure to a toxic substance, and chronic alcohol misuse (38, 39).

Some research suggests that individuals with celiac disease have a higher risk of this condition due to the presence of certain antibodies (40, 41).

Summary

Celiac disease is an autoimmune disorder associated with diarrhea, constipation, fatigue, chronic pain, depression, anxiety, unintentional weight loss, and other symptoms.

Although celiac disease is the most severe form of gluten intolerance, 0.5–13% of people may also have non-celiac gluten sensitivity, a milder gluten-related disorder (42, 43).

Here are some of the most common symptoms of non-celiac gluten sensitivity.

1. Bloating

Bloating is when you feel as if your belly is swollen or full of gas after you’ve eaten (44).

Although this uncomfortable condition has many explanations, it can occur among people who are sensitive or intolerant to gluten (45, 46).

Furthermore, research shows that the symptoms of non-celiac gluten sensitivity include bloating and abdominal discomfort (47).

But if you experience frequent bloating, you may have another underlying condition.

2. Diarrhea and constipation

Occasionally getting diarrhea and constipation is typical, but it may be a cause for concern if it happens regularly.

For people with gluten sensitivity, eating gluten-containing foods may trigger these digestive issues (48, 49).

3. Stomach pain

Abdominal pain is common and has numerous causes. However, it’s also the single most common symptom of gluten intolerance (50).

If you have gluten intolerance, you may experience abdominal pain and discomfort after eating gluten (51).

4. Headaches and migraine

Many people experience headaches or migraine attacks once in a while. Migraine is a common condition, affecting roughly one in every six adults in the United States (52).

Some studies show that people with gluten intolerance may be more prone to migraine episodes than others (53, 54).

You may be sensitive to gluten if you have regular headaches or migraine episodes without any apparent cause.

5. Fatigue

Feeling tired is very common and usually not linked to any condition. However, if you constantly feel very tired, an underlying cause may exist.

People with gluten intolerance are prone to fatigue and tiredness, especially after eating gluten-containing foods (51, 55).

6. Depression and anxiety

About 19% of US adults had an anxiety disorder in the past year (56).

Anxiety involves feelings of worry, nervousness, unease, and agitation. It often goes hand in hand with depression (57).

Individuals with gluten intolerance seem more prone to anxiety and depression than those without underlying conditions (58, 59, 60).

Several studies have also shown that people with depression and self-reported gluten intolerance feel better on a gluten-free diet and want to continue it, even if their digestive symptoms aren’t entirely resolved (60, 58).

These findings suggest that gluten exposure alone may induce feelings of depression, regardless of digestive symptoms.

7. Pain

Gluten exposure may cause inflammation in those with gluten sensitivity. This inflammation may result in widespread pain, including in your joints and muscles (51).

People with gluten sensitivity also seem more likely to experience arm and leg numbness. While the exact cause remains unknown, some studies link this symptom to the presence of antibodies related to gluten intolerance (61, 62).

8. Brain fog

“Brain fog” refers to the feeling of being unable to think clearly. It’s often described as:

• being forgetful
• having difficulty thinking
• feeling “cloudy”
• experiencing mental fatigue

Brain fog is a common symptom of gluten intolerance. In one 2020 study, it affected 48% of participants with non-celiac gluten intolerance. This may be caused by a reaction to certain antibodies in gluten though the exact reason is unknown (51, 63).

Summary

Non-celiac gluten sensitivity is a form of gluten intolerance that may cause headaches, depression, anxiety, brain fog, fatigue, pain, and digestive problems.

Wheat allergy is a food allergy that causes your body’s immune system to react to certain proteins found in wheat, including gluten and other compounds (64).

Wheat allergy is more common among children than adults. It’s estimated that approximately 66% of children outgrow wheat allergies by age 12 (64).

Here are a few of the most common symptoms.

1. Skin rash

Like other types of gluten intolerance, wheat allergies may be associated with certain skin conditions.

In particular, wheat allergies often cause hives, a skin rash characterized by itching and inflammation (65).

Typically, this reaction occurs shortly after a person eats wheat products and slowly subsides over time (66).

2. Digestive issues

Studies show that people who are allergic to wheat often report digestive issues, such as (67):

• nausea
• vomiting
• stomach cramps
• diarrhea

Food allergies can also trigger other digestive symptoms, including (68):

• bloating
• pain
• indigestion

This is due to your body’s immune response, which is triggered once you eat an allergen like wheat (69).

3. Nasal congestion

Sneezing, nasal congestion, and a runny nose may also be signs of a wheat allergy (70).

In some cases, a person with a wheat allergy having nasal symptoms can develop baker’s asthma, a type of occupational asthma caused by frequently breathing in bread flour (71, 72).

4. Anaphylaxis

Anaphylaxis is a severe allergic reaction that can be life threatening if left untreated (73).

It causes serious symptoms, including swelling, hives, nausea, vomiting, and difficulty breathing after exposure to an allergen, such as wheat (73).

Although symptoms usually begin within minutes of exposure, they may occur up to an hour later (74).

Treatment generally involves using epinephrine, a medication injected directly into your skin after the onset of anaphylaxis. However, people who experience anaphylaxis should get emergency medical attention, even if they have self-administered epinephrine (74).

Summary

Wheat allergy is a type of food allergy that may cause skin rashes, digestive issues, nasal congestion, and anaphylaxis.

Since so many symptoms overlap between different gluten-related disorders, it can be difficult to determine which — if any — is responsible.

Keep in mind that while people often refer to “gluten allergy,” it’s more likely that they mean gluten intolerance, wheat allergy, or celiac disease.

If you suspect you have one of these conditions, it’s first helpful to identify any links between symptoms and specific foods you’re eating. Collecting as much information as you can is a good starting point.

You can make an appointment to discuss your findings with a doctor. Combining personal dietary insight with a comprehensive health exam may help lead to an accurate diagnosis.

Once you know your condition, you can make diet and lifestyle adjustments as needed.

Here are some of the most commonly reported symptoms of gluten intolerance, wheat allergy, and celiac disease (67, 75, 76):

A registered dietitian or another health professional can provide the appropriate exams and testing.

Summary

Symptoms of gluten intolerance, wheat allergy, and celiac disease often overlap, making it difficult to identify the condition. The best way to get a diagnosis is to work closely with a doctor for the necessary testing and exam.

Gluten-related disorders may have numerous symptoms and can be frustrating to identify.

Remember that these conditions are common and may differ widely in severity. Know that you aren’t alone and that there are resources to help.

Speak with a doctor or dietitian for an accurate diagnosis, which will involve a comprehensive evaluation of your symptoms and potential testing. You can create a diet and lifestyle plan to help control symptoms.

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